View source for Reliability of Wikipedia

{{Short description|none}}
{{pp-semi-indef}}
{{pp-move}}
{{self-reference|This is an encyclopedic article discussing Wikipedia's reliability. For Wikipedia's own standpoint on reliability, see [[Wikipedia:General disclaimer]].}}
{{Use mdy dates|date=May 2024}}
[[File:Coati (Nasua nasua) at Parque Nacional da Serra dos Órgãos, Teresópolis, Brazil.jpg|thumb|A [[South American coati]]. In July 2008, a 17-year-old student added an invented nickname to the Wikipedia article [[Coati]] as a private joke, calling them "Brazilian [[aardvark]]s". The false information lasted for six years and was propagated by hundreds of websites, several newspapers, and even a few books published by university presses.<ref name="NewYorker_May19_2014">{{cite magazine|title=How a raccoon became an aardvark|url=http://www.newyorker.com/tech/elements/how-a-raccoon-became-an-aardvark|first=Eric|last=Randall|date=May 19, 2014|magazine=The New Yorker|url-status=live|archive-url=https://web.archive.org/web/20161229170809/http://www.newyorker.com/tech/elements/how-a-raccoon-became-an-aardvark|archive-date=December 29, 2016|access-date=November 24, 2016}}</ref><ref name="RegisterKolbe">{{cite web|title=Happy birthday: Jimbo Wales' sweet 16 Wikipedia fails. From aardvark to Bicholim, the encylopedia {{sic|nolink=y}} of things that never were|url=https://www.theregister.co.uk/2017/01/16/wikipedia_16_birthday_fails/|first=Andreas|last=Kolbe|date=January 16, 2017|work=The Register|url-status=live|archive-url=https://web.archive.org/web/20170708162916/http://www.theregister.co.uk/2017/01/16/wikipedia_16_birthday_fails/|archive-date=July 8, 2017|access-date=June 4, 2017}}</ref>]]

The '''reliability of Wikipedia''' and its volunteer-driven and community-regulated [[#Wikipedia editing model|editing model]], particularly its [[English Wikipedia|English-language edition]], has been questioned and tested. [[Wikipedia]] is written and edited by volunteer editors (known as [[Wikipedian]]s) who generate online content with the editorial oversight of other volunteer editors via community-generated policies and guidelines. The reliability of the project has been tested statistically through comparative review, analysis of the historical patterns, and strengths and weaknesses inherent in its editing process.<ref>{{Cite news |title= Snared in the Web of a Wikipedia Liar |first= Katharine Q. |last= Seelye |date= December 5, 2005 |work= [[The New York Times]] |url= https://www.nytimes.com/2005/12/04/weekinreview/04seelye.html |access-date= February 23, 2017 |archive-url= https://web.archive.org/web/20140907013706/http://www.nytimes.com/2005/12/04/weekinreview/04seelye.html |archive-date= September 7, 2014 |url-status= live }}</ref> The online encyclopedia has been [[Criticism of Wikipedia|criticized for its factual unreliability]], principally regarding its content, presentation, and [[Criticism of Wikipedia#Criticism of the community|editorial processes]]. [[Academic studies about Wikipedia|Studies and surveys]] attempting to gauge the reliability of Wikipedia have mixed results. Wikipedia's reliability was frequently criticized in the 2000s but has been improved; its English-language edition has been generally praised in the late 2010s and early 2020s.<ref name="Wiki20">{{cite news|date=January 9, 2021|title=Wikipedia is 20, and its reputation has never been higher|newspaper=[[The Economist]]|url=https://www.economist.com/international/2021/01/09/wikipedia-is-20-and-its-reputation-has-never-been-higher|access-date=February 25, 2021|archive-date=January 8, 2021|archive-url=https://web.archive.org/web/20210108205244/https://www.economist.com/international/2021/01/09/wikipedia-is-20-and-its-reputation-has-never-been-higher|url-status=live}}</ref><ref name="Last best">{{cite news|last1=Cooke|first1=Richard|date=February 17, 2020|title=Wikipedia Is the Last Best Place on the Internet|language=en-us|magazine=[[Wired (magazine)|Wired]]|url=https://www.wired.com/story/wikipedia-online-encyclopedia-best-place-internet/|access-date=October 13, 2020|archive-date=January 10, 2021|archive-url=https://web.archive.org/web/20210110150242/https://www.wired.com/story/wikipedia-online-encyclopedia-best-place-internet/|url-status=live}}</ref><ref name="Econ21">{{Cite news|date=January 9, 2021|title=Happy Birthday, Wikipedia|newspaper=[[The Economist]]|url=https://www.economist.com/leaders/2021/01/09/happy-birthday-wikipedia|access-date=February 16, 2022|archive-date=January 8, 2021|archive-url=https://web.archive.org/web/20210108171842/https://www.economist.com/leaders/2021/01/09/happy-birthday-wikipedia|url-status=live}}</ref>
[[File:Klee-Irwin.gif|thumb|Article instability and susceptibility to [[List of cognitive biases|cognitive bias]]es are two potential problem areas in a crowdsourced work like Wikipedia.]]

Select assessments of its reliability have examined how quickly [[Vandalism on Wikipedia|vandalism]]—content perceived by editors to constitute false or misleading information—is removed. Two years after the project was started, in 2003, an [[IBM]] study found that "vandalism is usually repaired extremely quickly—so quickly that most users will never see its effects".<ref>Fernanda B. Viégas, Martin Wattenberg, Kushal Dave: [http://alumni.media.mit.edu/~fviegas/papers/history_flow.pdf Studying Cooperation and Conflict between Authors with history flow Visualizations] {{Webarchive|url=https://web.archive.org/web/20060125025047/http://alumni.media.mit.edu/~fviegas/papers/history_flow.pdf|date=January 25, 2006}}. Proceedings of the [[CHI (conference)|SIGCHI conference on Human factors in computing systems]], 575–582, Vienna 2004, {{ISBN|1-58113-702-8}}</ref><ref name="History flow: results"/> The inclusion of false or fabricated content has, at times, lasted for years on Wikipedia due to its volunteer editorship.<ref name="TimesFrenchWPHoax" /><ref name="SeigenthalerUSAToday" /> Its editing model facilitates multiple systemic biases, namely [[selection bias]], [[Cherry picking|inclusion bias]], [[participation bias]], and [[Groupthink|group-think bias]]. The majority of the encyclopedia is written by male editors, leading to a [[Gender bias on Wikipedia|gender bias in coverage]], and the make up of the editing community has prompted concerns about [[Racial bias on Wikipedia|racial bias]], [[Spin (propaganda)|spin bias]], corporate bias, and national bias, among others.<ref>{{Cite news|last=Torres|first=Nicole|date=June 2, 2016|title=Why Do So Few Women Edit Wikipedia?|work=Harvard Business Review|url=https://hbr.org/2016/06/why-do-so-few-women-edit-wikipedia|access-date=June 26, 2020|issn=0017-8012|archive-date=June 17, 2020|archive-url=https://web.archive.org/web/20200617014645/https://hbr.org/2016/06/why-do-so-few-women-edit-wikipedia|url-status=live}}</ref><ref name="Fast Company">{{cite web|last1=Cassano|first1=Jay|title=Black History Matters, So Why Is Wikipedia Missing So Much Of It?|url=http://www.fastcoexist.com/3041572/black-history-matters-so-why-is-wikipedia-missing-so-much-of-it|url-status=live|archive-url=https://web.archive.org/web/20150510040813/http://www.fastcoexist.com/3041572/black-history-matters-so-why-is-wikipedia-missing-so-much-of-it|archive-date=May 10, 2015|access-date=April 13, 2015|website=[[Fast Company (magazine)|Fast Company]]|date=January 29, 2015}}</ref><ref>{{Cite magazine|last=Cooke|first=Richard|date=January 2, 2020|title=Wikipedia Is the Last Best Place on the Internet|language=en-us|magazine=Wired|url=https://www.wired.com/story/wikipedia-online-encyclopedia-best-place-internet/|access-date=January 2, 2020|issn=1059-1028|archive-date=January 10, 2021|archive-url=https://web.archive.org/web/20210110150242/https://www.wired.com/story/wikipedia-online-encyclopedia-best-place-internet/|url-status=live}}</ref> An [[ideological bias on Wikipedia]] has also been identified on both conscious and subconscious levels. A series of studies from [[Harvard Business School]] in 2012 and 2014 found Wikipedia "significantly more biased" than ''[[Encyclopædia Britannica]]'' but attributed the finding more to the length of the online encyclopedia as opposed to slanted editing.<ref>{{Cite news|last=Frick|first=Walter|date=December 3, 2014|title=Wikipedia Is More Biased Than Britannica, but Don't Blame the Crowd|work=Harvard Business Review|url=https://hbr.org/2014/12/wikipedia-is-more-biased-than-britannica-but-dont-blame-the-crowd|access-date=June 20, 2020|issn=0017-8012|archive-date=June 26, 2020|archive-url=https://web.archive.org/web/20200626165654/https://hbr.org/2014/12/wikipedia-is-more-biased-than-britannica-but-dont-blame-the-crowd|url-status=live}}</ref><ref>{{Cite journal|last1=Greenstein|first1=Shane|last2=Zhu|first2=Feng|date=January 1, 2012|title=Is Wikipedia Biased?|url=https://www.hbs.edu/faculty/Pages/item.aspx?num=45147|journal=American Economic Review|language=en-us|publisher=[[Harvard Business School]]|volume=103|access-date=June 26, 2020|archive-date=December 30, 2019|archive-url=https://web.archive.org/web/20191230092624/https://www.hbs.edu/faculty/Pages/item.aspx?num=45147|url-status=live}}</ref>

Instances of non-neutral or conflict-of-interest editing and the use of Wikipedia for "revenge editing" has attracted attention to false, biased, or defamatory content in articles, especially biographies of living people.<ref>{{cite web | url=http://www.salon.com/2013/05/17/revenge_ego_and_the_corruption_of_wikipedia/ | title=Revenge, ego and the corruption of Wikipedia | work=Salon | date=May 17, 2013 | access-date=June 4, 2016 | author=Leonard, Andrew | archive-url=https://web.archive.org/web/20160531215546/http://www.salon.com/2013/05/17/revenge_ego_and_the_corruption_of_wikipedia/ | archive-date=May 31, 2016 | url-status=live }}</ref><ref>{{cite web | url=https://www.theatlantic.com/business/archive/2015/08/wikipedia-editors-for-pay/393926/ | title=The Covert World of People Trying to Edit Wikipedia—for Pay | work=[[The Atlantic]] | date=August 11, 2015 | access-date=June 4, 2016 | author=Pinsker, Joe | archive-url=https://web.archive.org/web/20160601002855/http://www.theatlantic.com/business/archive/2015/08/wikipedia-editors-for-pay/393926/ | archive-date=June 1, 2016 | url-status=live }}</ref>  Articles on less technical subjects, such as the social sciences, humanities, and culture, have been known to deal with [[#Propagation of misinformation|misinformation cycles]], [[cognitive bias]]es, [[#Coverage|coverage discrepancies]], and editor disputes. The online encyclopedia does not guarantee the validity of its information.  It is seen as a valuable "[[#Expert opinion|starting point]]" for researchers when they pass over content to examine the listed references, citations, and sources. Academics suggest reviewing reliable sources when assessing the quality of articles.<ref name="Petiška 016555151988860">{{Cite journal|last1=Petiška|first1=Eduard|last2=Moldan|first2=Bedřich|date=December 9, 2019|title=Indicator of quality for environmental articles on Wikipedia at the higher education level|journal=Journal of Information Science|volume=47|issue=2|language=en-US|pages=269–280|doi=10.1177/0165551519888607|s2cid=214401940|issn=0165-5515}}</ref><ref>{{Cite web|last=Harrison|first=Stephen|date=March 19, 2020|title=The Coronavirus Is Stress-Testing Wikipedia's Systems—and Editors|url=https://slate.com/technology/2020/03/coronavirus-wikipedia-policies.html|access-date=July 10, 2020|website=Slate Magazine|language=en|archive-date=April 18, 2020|archive-url=https://web.archive.org/web/20200418195356/https://slate.com/technology/2020/03/coronavirus-wikipedia-policies.html|url-status=live}}</ref>

Its coverage of [[Health information on Wikipedia|medical and scientific articles]] such as [[pathology]],<ref name="Wood">{{cite journal|last=Wood|first=A|author2=Struthers, K|year=2010|title=Pathology education, Wikipedia and the Net generation|journal=Medical Teacher|volume=32|issue=7|pages=618–620|doi=10.3109/0142159X.2010.497719|pmid=20653388|quote=We have identified Wikipedia as an informative and accurate source for Pathology education and believe that Wikipedia is potentially an important learning tool for of the 'Net Generation'.|doi-access=free}}</ref> [[toxicology]],<ref name="Tox09" /> [[oncology]],<ref name="Leithner">{{cite journal|last=Leithner|first=A|author2=Maurer-Ertl, W|author3=Glehr, M|author4=Friesenbichler, J|author5=Leithner, K|author6=Windhager, R|date=Jul–Aug 2010|title=Wikipedia and osteosarcoma: a trustworthy patients' information?|journal=Journal of the American Medical Informatics Association|volume=17|issue=4|pages=373–4|doi=10.1136/jamia.2010.004507|pmc=2995655|pmid=20595302}}</ref> [[pharmaceuticals]],<ref name="Drug08" /> and [[psychiatry]]<ref name="Reavley">{{Cite journal|last1=Reavley|first1=N. J.|last2=MacKinnon|first2=A. J.|last3=Morgan|first3=A. J.|last4=Alvarez-Jimenez|first4=M.|last5=Hetrick|first5=S. E.|last6=Killackey|first6=E.|last7=Nelson|first7=B.|last8=Purcell|first8=R.|last9=Yap|first9=M. B. H.|last10=Jorm|first10=A. F.|year=2011|title=Quality of information sources about mental disorders: A comparison of Wikipedia with centrally controlled web and printed sources|journal=Psychological Medicine|volume=42|issue=8|pages=1753–1762|doi=10.1017/S003329171100287X|pmid=22166182|hdl-access=free|hdl=11343/59260|s2cid=13329595}}</ref> were compared to professional and peer-reviewed sources in a 2005 ''[[Nature (journal)|Nature]]'' study''.''<ref name="GilesJ2005Internet">{{Cite journal|last1=Giles|first1=J.|author-link=Jim Giles (reporter)|year=2005|title=Internet encyclopaedias go head to head: Jimmy Wales' Wikipedia comes close to Britannica in terms of the accuracy of its science entries|journal=[[Nature (journal)|Nature]]|volume=438|issue=7070|pages=900–1|bibcode=2005Natur.438..900G|doi=10.1038/438900a|pmid=16355180|doi-access=free}} The study (which was not in itself peer-reviewed) was cited in many news articles such as this: {{cite news|date=December 15, 2005|title=Wikipedia survives research test|work=[[BBC News]]|publisher=[[British Broadcasting Corporation|BBC]]|url=http://news.bbc.co.uk/2/hi/technology/4530930.stm|url-status=live|access-date=July 18, 2006|archive-url=https://web.archive.org/web/20120807165903/http://news.bbc.co.uk/2/hi/technology/4530930.stm|archive-date=August 7, 2012}}</ref> A year later ''Encyclopædia Britannica'' disputed the ''Nature'' study, whose authors, in turn, replied with a further rebuttal.<ref>{{cite web|author=Nature |url=http://www.nature.com/nature/britannica/index.html |title=Nature's responses to Encyclopaedia Britannica |publisher=Nature.com |date=March 30, 2006 |access-date=March 19, 2012|archive-url=https://web.archive.org/web/20061105172011/http://www.nature.com/nature/britannica/index.html|archive-date=November 5, 2006|url-status=dead}}</ref><ref>[http://corporate.britannica.com/britannica_nature_response.pdf Fatally Flawed: Refuting the recent study on encyclopedic accuracy by the journal ''Nature'']. {{webarchive|url=https://web.archive.org/web/20160709053629/http://corporate.britannica.com/britannica_nature_response.pdf |date=July 9, 2016 }} ''Encyclopædia Britannica'', March 2006</ref> Concerns regarding readability and the overuse of technical language were raised in studies published by the [[American Society of Clinical Oncology]] (2011),<ref>{{cite journal | last1 = Rajagopalan | first1 = M. S. | last2 = Khanna | first2 = V. K. | last3 = Leiter | first3 = Y. | last4 = Stott | first4 = M. | last5 = Showalter | first5 = T. N. | last6 = Dicker | first6 = A. P. | last7 = Lawrence | first7 = Y. R. | doi = 10.1200/JOP.2010.000209 | title = Patient-Oriented Cancer Information on the Internet: A Comparison of Wikipedia and a Professionally Maintained Database | journal = Journal of Oncology Practice | volume = 7 | issue = 5 | pages = 319–323 | year = 2011 | pmid = 22211130 | pmc =3170066 }}</ref> ''[[Psychological Medicine (journal)|Psychological Medicine]]'' (2012),<ref name="Reavley" /> and ''[[European Journal of Gastroenterology and Hepatology]]'' (2014).<ref>{{cite journal | last1 = Azer | first1 = S. A. | title = Evaluation of gastroenterology and hepatology articles on Wikipedia | doi = 10.1097/MEG.0000000000000003 | journal = European Journal of Gastroenterology & Hepatology | volume = 26 | issue = 2 | pages = 155–63 | year = 2014 | pmid = 24276492 | s2cid = 7760287}}</ref> The [[Simple English Wikipedia]] serves as a simplified version of articles to make complex articles more accessible to the layperson on a given topic in [[Basic English]]. Wikipedia's popularity, mass readership, and free accessibility has led the encyclopedia to command a substantial second-hand cognitive authority across the world.<ref>{{cite news|last=Barnett|first=David|date=February 17, 2018|title=Can we trust Wikipedia? 1.4 billion people can't be wrong|url=http://www.independent.co.uk/news/long_reads/wikipedia-explained-what-is-it-trustworthy-how-work-wikimedia-2030-a8213446.html|access-date=July 15, 2021|work=The Independent|archive-date=February 11, 2019|archive-url=https://web.archive.org/web/20190211185638/https://www.independent.co.uk/news/long_reads/wikipedia-explained-what-is-it-trustworthy-how-work-wikimedia-2030-a8213446.html|url-status=live}}</ref><ref>{{cite magazine|last=Mak|first=Aaron|date=May 28, 2019|title=Inside the Brutal, Petty War Over Donald Trump's Wikipedia Page|url=https://slate.com/technology/2019/05/donald-trump-wikipedia-page.html|access-date=July 15, 2020|magazine=Slate|archive-date=June 15, 2021|archive-url=https://web.archive.org/web/20210615214408/https://slate.com/technology/2019/05/donald-trump-wikipedia-page.html|url-status=live}}</ref>{{refn|Its reliability has received wide-spread media coverage and is [[Wikipedia in culture|frequently featured]] in popular culture.|group=nb}}

{{TOC level|3}}

== Wikipedia editing model ==
Wikipedia allows anonymous editing; contributors (known as "editors") are not required to provide any identification or an email address. A 2009 study of [[Dartmouth College]] in the English Wikipedia noted that, contrary to usual social expectations, anonymous editors were some of Wikipedia's most productive contributors of valid content.<ref name="samaritan">{{cite journal |last1=Anthony |first1=Denise |last2=Smith |first2=Sean W. |last3=Williamson |first3=Timothy |date=July 20, 2009 |title=Reputation and Reliability in Collective Goods |journal=Rationality and Society |language=en |volume=21 |issue=3 |pages=283–306 |doi=10.1177/1043463109336804|citeseerx=10.1.1.299.9401 |s2cid=146210753 }}</ref> The Dartmouth study was criticized by John Timmer of ''[[Ars Technica]]'' for its methodological shortcomings.<ref name="Dartmouth">{{cite web|url=https://arstechnica.com/news.ars/post/20071018-anonymous-good-samaritans-may-produce-wikipedias-best-content.html|title=Anonymous "good samaritans" produce Wikipedia's best content, says study|first=John|last=Timmer|website=Ars Technica|date=October 18, 2007|access-date=October 27, 2007|quote=Good samaritans with less than 100 edits made higher-quality contributions than those with registered accounts and equal amounts of content. In fact, anonymous contributors with a single edit had the highest quality of any group. But quality steadily declined, and more-frequent anonymous contributors were anything but Samaritans; their contributions generally didn't survive editing... The authors also recognize that contributions in the form of stubs on obscure topics might survive unaltered indefinitely, inflating the importance of single contributions...Objective ratings of quality are difficult, and it's hard to fault the authors for attempting to find an easily-measured proxy for it. In the absence of independent correlation, however, it's not clear that the measurement used actually works as a proxy. Combined with the concerns regarding anonymous contributor identity, there are enough problems with this study that the original question should probably be considered unanswered, regardless of how intuitively satisfying these results are.|archive-url=https://web.archive.org/web/20071026031829/http://arstechnica.com/news.ars/post/20071018-anonymous-good-samaritans-may-produce-wikipedias-best-content.html|archive-date=October 26, 2007|url-status=live}}</ref>

Wikipedia trusts the same community to self-regulate and become more proficient at [[quality control]]. Wikipedia has harnessed the work of millions of people to produce the world's largest knowledge-based site along with software to support it, resulting in more than nineteen million articles written, across more than 280 different language versions, in fewer than twelve years.<ref>{{cite web |url=http://s23.org/wikistats/wikipedias_html |title=WikiStats by S23 – List of Wikipedias |publisher=s23Wiki |archive-url=https://web.archive.org/web/20110718010941/http://s23.org/wikistats/wikipedias_html |archive-date=July 18, 2011 }}</ref> For this reason, there has been considerable interest in the project both academically and from diverse fields such as [[information technology]], [[business]], [[project management]], knowledge acquisition, [[software programming]], other [[collaborative]] projects and [[sociology]], to explore whether the Wikipedia model can produce quality results, what collaboration in this way can reveal about people and whether the scale of involvement can overcome the obstacles of individual limitations and poor editorship which would otherwise arise.{{citation needed|date=August 2021}}

Wikipedia's degree of truthfulness extends from its technology, policies, and editor culture. Edit histories are publicly visible. Footnotes show the origins of claims. Editors remove unverifiable claims and overrule ("revert") claims not phrased in a neutral point of view (NPOV). Wikipedia editors also tend towards self-examination and acknowledge Wikipedia's flaws. Its open model permits article-tampering (vandalism) including short-lived jokes and longer hoaxes. Some editors dedicate as much time to [[trolling]] (creating vandalism, spam, and harassment) as others do improving the encyclopedia. The English Wikipedia's editor pool, roughly 40,000 active editors who make five edits monthly, largely skews male and white, leading to gender- and race-based [[Criticism of Wikipedia#Systemic bias in coverage|systemic biases in coverage]]. Variations in coverage mean that Wikipedia can be both, as online communities professor [[Amy S. Bruckman]] put it, "the most accurate form of information ever created by humans" on the whole while short articles can be "total garbage".{{r|NYT & ChatGPT}}

Academics view Wikipedia as representing a "consensus truth" in which readers can check reality in an age of contested facts. For example, when facts surrounding the [[COVID-19 pandemic]] rapidly changed or were debated, editors removed claims that did not adhere to the "verifiability" and "NPOV" guidelines.{{r|NYT & ChatGPT}}

=== Fact-checking ===
{{main|Wikipedia and fact-checking}}

Fact-checking of Wikipedia is the process through which Wikipedia editors perform [[fact-checking]] of content published in Wikipedia, while fact-checking using Wikipedia is the use of Wikipedia for fact-checking other publications. The broader topic of fact checking in the context of Wikipedia also includes the cultural discussion of the place of Wikipedia in fact-checking. Major platforms including [[YouTube]]<ref name="Glaser 2018">{{cite web |last1=Glaser |first1=April |title=YouTube Is Adding Fact-Check Links for Videos on Topics That Inspire Conspiracy Theories |url=https://slate.com/technology/2018/08/youtube-is-adding-fact-check-links-from-wikipedia-and-encyclopedia-britannica-for-videos-on-topics-that-inspire-conspiracy-theories.html |website=[[Slate (magazine)|Slate Magazine]] |language=en |date=August 14, 2018 |access-date=January 23, 2021 |archive-date=January 26, 2021 |archive-url=https://web.archive.org/web/20210126060718/https://slate.com/technology/2018/08/youtube-is-adding-fact-check-links-from-wikipedia-and-encyclopedia-britannica-for-videos-on-topics-that-inspire-conspiracy-theories.html |url-status=live }}</ref> and [[Facebook]]<ref name="Flynn 2017">{{cite web |last1=Flynn |first1=Kerry |title=Facebook outsources its fake news problem to Wikipedia—and an army of human moderators |url=https://mashable.com/2017/10/05/facebook-wikipedia-context-articles-news-feed/ |website=[[Mashable]] |language=en |date=October 5, 2017 |access-date=January 23, 2021 |archive-date=December 4, 2020 |archive-url=https://web.archive.org/web/20201204004531/https://mashable.com/2017/10/05/facebook-wikipedia-context-articles-news-feed/ |url-status=live }}</ref> use Wikipedia's content to confirm the accuracy of information in their own media collections. Seeking public trust is a major part of Wikipedia's publication philosophy.<ref name="Iannucci 2017">{{cite web |last1=Iannucci |first1=Rebecca |title=What can fact-checkers learn from Wikipedia? We asked the boss of its nonprofit owner |url=https://www.poynter.org/fact-checking/2017/what-can-fact-checkers-learn-from-wikipedia-we-asked-the-boss-of-its-nonprofit-owner/ |website=[[Poynter Institute]] |date=July 6, 2017 |access-date=January 23, 2021 |archive-date=January 12, 2021 |archive-url=https://web.archive.org/web/20210112174026/https://www.poynter.org/fact-checking/2017/what-can-fact-checkers-learn-from-wikipedia-we-asked-the-boss-of-its-nonprofit-owner/ |url-status=live }}</ref>

Wikipedia has grown beyond a simple encyclopedia to become what ''[[The New York Times]]'' called a "factual netting that holds the digital world together".<ref name="NYT & ChatGPT">{{Cite news| issn = 0362-4331| last = Gertner| first = Jon| title = Wikipedia's Moment of Truth| work = The New York Times| access-date = 2024-05-23| date = 2023-07-18| url = https://www.nytimes.com/2023/07/18/magazine/wikipedia-ai-chatgpt.html}}</ref> Common questions asked of search engines are answered using knowledge ingested from Wikipedia, and often credit or link to Wikipedia as their source. Wikipedia is likely the most important single source used to train generative [[artificial intelligence]] (AI) [[Large language models|models]], such as [[ChatGPT]], for which Wikipedia is valued as a well-curated data set with highly structured formatting.<ref>{{harvnb|Gertner|2023}}: "While estimates of its influence can vary, Wikipedia is probably the most important single source in the training of A.I. models. ... In fact, no one I spoke with in the tech community seemed to know if it would even be possible to build a good A.I. model without Wikipedia."</ref> The accuracy of AI models depend on the quality of their training data, but these models are also fundamentally unable to cite their original source for their knowledge, thus AI users use Wikipedia knowledge without knowing that Wikipedia is its source. AI users also receive results that intertwine facts originating from Wikipedia with fictional data points ([[AI hallucination]]s), lowering the quality of information absent a real-time fact-check during information retrieval.{{r|NYT & ChatGPT}}

== Assessments ==
{{Update|section|date=March 2022}}

=== Criteria for evaluating reliability ===
The reliability of Wikipedia articles can be measured by the following criteria:[[File:Wikipedia vandalism.svg|thumb|[[Vandalism on Wikipedia|Vandalism of a Wikipedia article]]. The section on the left is the normal, undamaged version; and on the right is the vandalized, damaged version.]]
* Accuracy of information provided within articles
* Appropriateness of the images provided with the article
* Appropriateness of the style and focus of the articles<ref name="Stvilia2008Information">{{Cite journal |last1=Stvilia |first1=Besiki |last2=Twidale |first2=Michael B. |last3=Smith |first3=Linda C. |last4=Gasser |first4=Les |date=April 2008 |title=Information Quality Work Organization in Wikipedia |url=http://mailer.fsu.edu/~bstvilia/papers/stvilia_wikipedia_infoWork_p.pdf |url-status=dead |journal=[[Journal of the American Society for Information Science and Technology]] |volume=59 |issue=6 |pages=983–1001 |citeseerx=10.1.1.163.5109 |doi=10.1002/asi.20813 |s2cid=10156153 |archive-url=https://web.archive.org/web/20070820183345/http://mailer.fsu.edu/~bstvilia/papers/stvilia_wikipedia_infoWork_p.pdf |archive-date=August 20, 2007}}</ref>
* Susceptibility to, and exclusion and removal of, false information
* Comprehensiveness, scope and coverage within articles and in the range of articles
* Identification of reputable [[source text|third-party sources]] as [[citation]]s
* Verifiability of statements by respected sources<ref name="Petiška 016555151988860" />
* Stability of the articles
* Susceptibility to editorial and [[systemic bias]]
* Quality of writing

Several "market-oriented" extrinsic measures demonstrate that large audiences trust Wikipedia in one way or another. For instance, "50 percent of [US] physicians report that they've consulted ... [Wikipedia] for information on health conditions", according to a report from IMS Institute for Healthcare Informatics.<ref>{{cite news |last=Fearnow |first=Benjamin |date=January 31, 2014 |title=Report: Wikipedia The Top Source Of Health Care Info For Doctors, Patients |publisher=[[CBS]] |url=http://connecticut.cbslocal.com/2014/01/29/report-wikipedia-the-top-source-of-health-care-info-for-doctors-patients/ |url-status=live |access-date=February 1, 2014 |archive-url=https://web.archive.org/web/20140131062756/http://connecticut.cbslocal.com/2014/01/29/report-wikipedia-the-top-source-of-health-care-info-for-doctors-patients/ |archive-date=January 31, 2014}}</ref>

=== Comparative studies ===
On October 24, 2005, the British newspaper, ''[[The Guardian]]'', published a story entitled "Can you trust Wikipedia?" in which a panel of experts were asked to review seven entries related to their fields, giving each article reviewed a number designation from 0 to 10. Most of these reviewed articles received marks between 5 and 8. The most common critiques were poor prose, or ease-of-reading issues (three mentions), omissions or inaccuracies, often small but including key omissions in some articles (three mentions), and poor balance, with less important areas being given more attention and vice versa (one mention). The most common praises were factually sound and correct, no glaring inaccuracies (four mentions), and much useful information, including well-selected links, making it possible to "access much information quickly" (three mentions).<ref><!-- Can you trust Wikipedia? -->{{cite Q|Q110613135}}</ref>

In December 2005, the journal ''[[Nature (journal)|Nature]]'' published results of an attempted blind study seeking reviewer evaluations of the accuracy of a small subset of articles from Wikipedia and ''[[Encyclopædia Britannica]]''. The non-peer-reviewed study was based on ''Nature''{{'}}s selection of 42 articles on scientific topics, including biographies of well-known scientists. Factual errors, omissions or misleading statements found in the sampled articles was 162 for Wikipedia and 123 for ''Britannica'' (4:3). For serious errors, such as misinterpretations of important concepts, 4 were found in Wikipedia, and 4 in ''Britannica'' (1:1). The study concluded that "Wikipedia comes close to ''Britannica'' in terms of the accuracy of its science entries",<ref name="GilesJ2005Internet"/> although Wikipedia's articles were often "poorly structured".<ref name="GilesJ2005Internet"/>

''Encyclopædia Britannica'' expressed concerns, leading ''Nature'' to release further documentation of its survey method.<ref>{{Cite news|url=http://www.nature.com/news/2005/051212/exref/supplementary_information.doc |work=Nature |title=Supplementary information to accompany Nature news article 'Internet encyclopedias go head to head' |date=December 22, 2005 |url-status=dead |archive-url=https://web.archive.org/web/20070928012459/http://www.nature.com/news/2005/051212/exref/supplementary_information.doc |archive-date=September 28, 2007 }}</ref> Based on this additional information, ''Encyclopædia Britannica'' denied the validity of the ''Nature'' study, stating that it was "fatally flawed". Among ''Britannica''{{'}}s criticisms were that excerpts rather than the full texts of some of their articles were used, that some of the extracts were compilations that included articles written for the youth version, that ''Nature'' did not check the factual assertions of its reviewers, and that many points the reviewers labeled as errors were differences of editorial opinion. ''Britannica'' further stated that "While the heading proclaimed that 'Wikipedia comes close to ''Britannica'' in terms of the accuracy of its science entries,' the numbers buried deep in the body of the article said precisely the opposite: Wikipedia in fact had a third more inaccuracies than ''Britannica''. (As we demonstrate below, {{em|Nature}}'s research grossly exaggerated {{em|Britannica}}'s inaccuracies, so we cite this figure only to point out the slanted way in which the numbers were presented.)"<ref name=FF>{{cite web|url=http://corporate.britannica.com/britannica_nature_response.pdf|title=Fatally Flawed – Refuting the recent study on encyclopedic accuracy by the journal ''Nature''|date=March 2006|publisher=Encyclopædia Britannica, Inc.|access-date=June 30, 2009|archive-url=https://web.archive.org/web/20160709053629/http://corporate.britannica.com/britannica_nature_response.pdf|archive-date=July 9, 2016|url-status=live}}</ref> ''Nature'' acknowledged the compiled nature of some of the ''Britannica'' extracts, but denied that this invalidated the conclusions of the study.<ref>{{Cite journal| title = Britannica attacks | journal = [[Nature (journal)|Nature]]| volume = 440 | page = 582 | doi = 10.1038/440582b | date = March 30, 2006| pmid = 16572128 | issue = 7084 |bibcode = 2006Natur.440R.582. | doi-access = free }}</ref> ''Encyclopædia Britannica'' also argued that a breakdown of the errors indicated that the mistakes in Wikipedia were more often the inclusion of incorrect facts, while the mistakes in ''Britannica'' were "errors of omission", making "''Britannica'' far more accurate than ''Wikipedia'', according to the figures".<ref name=FF/> ''Nature'' has since rejected the ''Britannica'' response,<ref>{{cite news|url=http://news.bbc.co.uk/1/hi/technology/4840340.stm|title=Wikipedia study 'fatally flawed'|date=March 24, 2006|work=BBC News|access-date=May 31, 2011|archive-url=https://web.archive.org/web/20060714210009/http://news.bbc.co.uk/1/hi/technology/4840340.stm|archive-date=July 14, 2006|url-status=live}}</ref> stating that any errors on the part of its reviewers were not biased in favor of either encyclopedia, that in some cases it used excerpts of articles from both encyclopedias, and that ''Britannica'' did not share particular concerns with ''Nature'' before publishing its "open letter" rebuttal.<ref>{{cite web| title=Encyclopædia Britannica and Nature: a response| work=[[Nature (journal)|Nature]]| date=March 23, 2006| url=http://www.nature.com/press_releases/Britannica_response.pdf| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20071031053055/http://www.nature.com/press_releases/Britannica_response.pdf| archive-date=October 31, 2007| url-status=live| df=mdy-all}}</ref><ref>{{Cite news|url=http://www.nature.com/nature/britannica/eb_advert_response_final.pdf|work=Nature Press release|title=Encyclopædia Britannica and Nature: a response|date=March 23, 2006|access-date=May 31, 2011|archive-url=https://web.archive.org/web/20071031052930/http://www.nature.com/nature/britannica/eb_advert_response_final.pdf|archive-date=October 31, 2007|url-status=live}}</ref>

The point-for-point disagreement between these two parties that addressed the compilation/text excerpting and very small sample size issues—argued to bias the outcome in favor of Wikipedia, versus a comprehensive, full article, large sample size study favoring the quality-controlled format of ''Britannica''—have been echoed in online discussions,<ref>{{cite web |url=http://blog.sethroberts.net/2007/06/02/one-sided-critiques-of-the-day/ |title=Seth's Blog » Blog Archive » One-Sided Critiques of the Day |publisher=Blog.sethroberts.net |date=June 2, 2007 |access-date=April 29, 2014 |archive-url=https://web.archive.org/web/20140428133142/http://blog.sethroberts.net/2007/06/02/one-sided-critiques-of-the-day/ |archive-date=April 28, 2014 |url-status=live }}</ref><ref>{{cite web |url=http://blog.wikimedia.org/2012/08/02/seven-years-after-nature-pilot-study-compares-wikipedia-favorably-to-other-encyclopedias-in-three-languages/ |title=Seven years after Nature, pilot study compares Wikipedia favorably to other encyclopedias in three languages — Wikimedia blog |date=August 2, 2012 |publisher=Blog.wikimedia.org |access-date=April 29, 2014 |archive-url=https://web.archive.org/web/20140615100445/http://blog.wikimedia.org/2012/08/02/seven-years-after-nature-pilot-study-compares-wikipedia-favorably-to-other-encyclopedias-in-three-languages/ |archive-date=June 15, 2014 |url-status=live }}</ref> including of articles citing the ''Nature'' study, e.g., where a "flawed study design" for manual selection of articles/article portions, the lack of study "statistical power" in its comparing 40 articles from over 100,000 ''Britannica'' and over 1 million English Wikipedia articles, and the absence of any study statistical analyses (e.g., reported [[confidence interval]]s for study results) has also been noted.<ref>See author-acknowledged comments in response to the citation of the ''Nature'' study, at ''PLoS One'', 2014, [http://www.plosone.org/annotation/listThread.action?root=80078 ''Citation of fundamentally flawed ''Nature'' quality 'study{{'}}''], in response to T. Yasseri et al. (2012), ''Dynamics of Conflicts in Wikipedia'', published June 20, 2012, DOI 10.1371/journal.pone.0038869. Retrieved July 21, 2014. {{Webarchive|url=https://web.archive.org/web/20160116210930/http://www.plosone.org/annotation/listThread.action?root=80078 |date=January 16, 2016 }}.</ref> Science communicator [[Jonathan Jarry]] said in 2024 that the study was historically important, and had been cited in almost every science paper on Wikipedia's reliability since then, but that research of this kind will only provide a "snapshot" and quickly become unreliable.<ref name="Can You Trust Dr. Wikipedia? 2024">{{cite news |last1=Jarry |first1=Jonathan |author1-link=Jonathan Jarry |title=Can You Trust Dr. Wikipedia? |url=https://www.mcgill.ca/oss/article/critical-thinking-technology/can-you-trust-dr-wikipedia |access-date=7 September 2024 |work=[[Office for Science and Society]] |date=6 September 2024 |language=en}}</ref>

In June 2006, [[Roy Rosenzweig]], a professor specializing in American history, published a comparison of the Wikipedia biographies of 25 Americans to the corresponding biographies found on Encarta and ''American National Biography Online''. He wrote that Wikipedia is "surprisingly accurate in reporting names, dates, and events in U.S. history" and described some of the errors as "widely held but inaccurate beliefs". However, he stated that Wikipedia often fails to distinguish important from trivial details, and does not provide the best references. He also complained about Wikipedia's lack of "persuasive analysis and interpretations, and clear and engaging prose".<ref name=Rosenzweig>{{Cite journal|first=Roy |last=Rosenzweig |author-link=Roy Rosenzweig |title=Can History be Open Source? Wikipedia and the Future of the Past |journal=The Journal of American History |volume=93 |issue=1 |date=June 2006 |pages=117–146 |url=http://chnm.gmu.edu/essays-on-history-new-media/essays/?essayid=42 |access-date=August 11, 2006 |doi=10.2307/4486062 |url-status=dead |archive-url=https://web.archive.org/web/20100425130754/http://chnm.gmu.edu/essays-on-history-new-media/essays/?essayid=42 |archive-date=April 25, 2010 |jstor=4486062 |url-access=subscription }} (Center for History and New Media)</ref>{{refn|Wikipedia's policies on [[Wikipedia:No original research|original research]], including [[WP:SYNTH|unpublished synthesis of published data]], disallow new analysis and interpretation not found in [[Wikipedia:Reliable sources|reliable sources]].|group=nb}}

A web-based survey conducted from December 2005 to May 2006 by Larry Press, a professor of Information Systems at [[California State University at Dominguez Hills]], assessed the "accuracy and completeness of Wikipedia articles".<ref>{{cite web| title=Survey of Wikipedia accuracy and completeness| work=[[California State University at Dominguez Hills]]| date=May 2006| url=http://bpastudio.csudh.edu/fac/lpress/wikieval/| access-date=December 10, 2012| archive-url=https://web.archive.org/web/20140721105607/http://bpastudio.csudh.edu/fac/lpress/wikieval/| archive-date=July 21, 2014| url-status=live}}</ref> Fifty people accepted an invitation to assess an article. Of the fifty, seventy-six percent (76%) agreed or strongly agreed that the Wikipedia article was accurate, and forty-six percent (46%) agreed or strongly agreed that it was complete. Eighteen people compared the article they reviewed to the article on the same topic in the ''[[Encyclopædia Britannica]]''. Opinions on accuracy were almost equal between the two encyclopedias (6 favoring ''Britannica'', 7 favoring Wikipedia, 5 stating they were equal), and eleven of the eighteen (61%) found Wikipedia somewhat or substantially more complete, compared to seven of the eighteen (39%) for ''Britannica''. The survey did not attempt a random selection of the participants, and it is not clear how the participants were invited.<ref>{{cite web| title=Survey of Wikipedia accuracy and completeness| publisher=Larry Press, Professor of Computer Information Systems, California State University| year=2006| url=http://bpastudio.csudh.edu/fac/lpress/wikieval| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20110928205017/http://bpastudio.csudh.edu/fac/lpress/wikieval/| archive-date=September 28, 2011| url-status=live}}</ref>

The German computing magazine ''[[c't]]'' performed a comparison of ''[[Brockhaus Multimedial premium|Brockhaus Multimedial]]'', ''[[Encarta|Microsoft Encarta]]'', and the [[German Wikipedia]] in October 2004: Experts evaluated 66 articles in various fields. In overall score, Wikipedia was rated 3.6 out of 5 points (B-).<ref>Michael Kurzidim: Wissenswettstreit. Die kostenlose Wikipedia tritt gegen die Marktführer Encarta und Brockhaus an, in: [[c't]] 21/2004, October 4, 2004, S. 132–139.</ref> A second test by ''c't'' in February 2007 used 150 search terms, of which 56 were closely evaluated, to compare four digital encyclopedias: [[Bertelsmann]] Enzyklopädie 2007, Brockhaus Multimedial premium 2007, Encarta 2007 Enzyklopädie and Wikipedia. It concluded: "We did not find more errors in the texts of the free encyclopedia than in those of its commercial competitors."<ref>Dorothee Wiegand: "Entdeckungsreise. Digitale Enzyklopädien erklären die Welt." c't 6/2007, March 5, 2007, p. 136–145. Original quote: "Wir haben in den Texten der freien Enzyklopädie nicht mehr Fehler gefunden als in denen der kommerziellen Konkurrenz"</ref>

Viewing Wikipedia as fitting the economists' definition of a perfectly competitive marketplace of ideas, George Bragues ([[University of Guelph-Humber]]), examined Wikipedia's articles on seven top Western philosophers: [[Aristotle]], [[Plato]], [[Immanuel Kant]], [[René Descartes]], [[Georg Wilhelm Friedrich Hegel]], [[Thomas Aquinas]], and [[John Locke]]. Wikipedia's articles were compared to a consensus list of themes culled from four reference works in philosophy. Bragues found that, on average, Wikipedia's articles only covered 52% of consensus themes. No errors were found, though there were significant omissions.<ref>{{cite SSRN |last=Bragues |first=George |title=Wiki-Philosophizing in a Marketplace of Ideas: Evaluating Wikipedia's Entries on Seven Great Minds |date=April 2007 |ssrn=978177 }}</ref>

''[[PC Pro]]'' magazine (August 2007) asked experts to compare four articles (a small [[sample size|sample]]) in their scientific fields between Wikipedia, ''Britannica'' and Encarta. In each case Wikipedia was described as "largely sound", "well handled", "performs well", "good for the bare facts" and "broadly accurate". One article had "a marked deterioration towards the end" while another had "clearer and more elegant" writing, a third was assessed as less well written but better detailed than its competitors, and a fourth was "of more benefit to the serious student than its Encarta or Britannica equivalents". No serious errors were noted in Wikipedia articles, whereas serious errors were noted in one Encarta and one ''Britannica'' article.<ref name="uncovered">''PC Pro'' magazine, August 2007, p. 136, "Wikipedia Uncovered".</ref>

In October 2007, the Australian magazine ''PC Authority'' published a feature article on the accuracy of Wikipedia. The article compared Wikipedia's content to other popular online encyclopedias, namely ''[[Britannica]]'' and [[Encarta]]. The magazine asked experts to evaluate articles pertaining to their field. A total of four articles were reviewed by three experts. Wikipedia was comparable to the other encyclopedias, topping the chemistry category.<ref>{{cite web|url=http://www.pcauthority.com.au/Feature/93908,wikipedia-uncovered.aspx/1|title=''PC Authority'' – 'Wikipedia Uncovered'|access-date=December 31, 2008|archive-url=https://web.archive.org/web/20090226143321/http://www.pcauthority.com.au/Feature/93908,wikipedia-uncovered.aspx/1|archive-date=February 26, 2009|url-status=live}}</ref>

In December 2007, German magazine ''[[Stern (magazine)|Stern]]'' published the results of a comparison between the German Wikipedia and the online version of the 15-volume edition of ''[[Brockhaus Enzyklopädie]]''. The test was commissioned to a research institute (Cologne-based ''WIND GmbH''), whose analysts assessed 50 articles from each encyclopedia (covering politics, business, sports, science, culture, entertainment, geography, medicine, history and religion) on four criteria (accuracy, completeness, timeliness and clarity), and judged Wikipedia articles to be more accurate on the average (1.6 on a scale from 1 to 6 versus 2.3 for ''Brockhaus'', with 1 as the best and 6 as the worst). Wikipedia's coverage was also found to be more complete and up to date; however, ''Brockhaus'' was judged to be more clearly written, while several Wikipedia articles were criticized as being too complicated for non-experts, and many as too lengthy.<ref>{{cite magazine |date=December 2007 |title=Wikipedia: Wissen für alle |trans-title=Wikipedia: Knowledge for Everyone |volume=2007 |issue=50 |magazine=[[Stern (magazine)|Stern]] |pages=30–44 |quote=Einige Wikipedia-Artikel sind für Laien schlicht zu kompliziert, viele zu weitschweifig, urteilten die Tester. [Some Wikipedia articles are simply too complicated for laypersons, many too long-winded, judged the testers.] |language=de |last1=Schönert |first1=Ulf |last2=Güntheroth |first2=Horst |url=https://www.stern.de/digital/online/wikipedia--wissen-fuer-alle-3217272.html |access-date=January 11, 2023 |archive-date=January 11, 2023 |archive-url=https://web.archive.org/web/20230111175055/https://www.stern.de/digital/online/wikipedia--wissen-fuer-alle-3217272.html |url-status=live }}</ref><ref>{{cite magazine |date=December 5, 2007 |title=Wikipedia schlägt Brockhaus |trans-title=Wikipedia beats Brockhaus |url=http://www.stern.de/computer-technik/internet/:stern-Test-Wikipedia-Brockhaus/604423.html |magazine=[[Stern (magazine)|Stern]] |publisher=[[Gruner + Jahr]] |access-date=September 6, 2016 |language=de |archive-url=https://web.archive.org/web/20090802143802/http://www.stern.de/computer-technik/internet/:stern-Test-Wikipedia-Brockhaus/604423.html |archive-date=August 2, 2009 |url-status=live  }}</ref><ref>K.C. Jones: ''[http://www.informationweek.com/news/showArticle.jhtml?articleID=204702694 German Wikipedia Outranks Traditional Encyclopedia's Online Version] {{Webarchive|url=https://web.archive.org/web/20071212231601/http://www.informationweek.com/news/showArticle.jhtml?articleID=204702694 |date=December 12, 2007 }}''. [[InformationWeek]], December 7, 2007 <!--Note: This article incorrectly reports that Wikipedia articles were "judged ... more ... easy to read", in fact this was the one of the four areas where ''Brockhaus'' reached a better result (1.8 vs. 2.4 for Wikipedia)--></ref>

In its April 2008 issue British computing magazine ''[[PC Plus]]'' compared the English Wikipedia with the DVD editions of ''World Book Encyclopedia'' and ''Encyclopædia Britannica'', assessing for each the coverage of a series of random subjects. It concluded, "The quality of content is good in all three cases" and advised Wikipedia users "Be aware that erroneous edits do occur, and check anything that seems outlandish with a second source. But the vast majority of Wikipedia is filled with valuable and accurate information."<ref>{{cite web |first=Simon |last=Williams |url=http://www.techradar.com/news/internet/web/wikipedia-vs-encyclopaedia-a-question-of-trust-316163 |title=Wikipedia vs Encyclopaedia: A question of trust? |website=Techradar.com |date=April 21, 2008 |access-date=September 6, 2016 |archive-url=https://web.archive.org/web/20080705234729/http://www.techradar.com/news/internet/web/wikipedia-vs-encyclopaedia-a-question-of-trust-316163 |archive-date=July 5, 2008 |url-status=dead  }}</ref>

A 2008 paper in ''[[Reference Services Review]]'' compared nine Wikipedia entries on historical topics to their counterparts in ''Encyclopædia Britannica'', ''The Dictionary of American History'' and ''American National Biography Online''. The paper found that Wikipedia's entries had an overall accuracy rate of 80 percent, whereas the other encyclopedias had an accuracy rate of 95 to 96 percent.<ref>{{cite journal|last1=Rector|first1=Lucy Holman|title=Comparison of ''Wikipedia'' and other encyclopedias for accuracy, breadth, and depth in historical articles|journal=Reference Services Review|volume=36|issue=1|pages=7–22|doi=10.1108/00907320810851998|year=2008}}</ref>

A 2010 study assessed the extent to which Wikipedia pages about the history of countries conformed to the site's policy of verifiability. It found that, in contradiction of this policy, many claims in these articles were not supported by citations, and that many of those that were, sourced to popular media and government websites rather than to academic journal articles.<ref>{{Cite journal |last1=Luyt |first1=Brendan |last2=Tan |first2=Daniel |date=April 1, 2010 |title=Improving Wikipedia's credibility: References and citations in a sample of history articles |journal=Journal of the American Society for Information Science and Technology |volume=61 |issue=4 |pages=715–722 |doi=10.1002/asi.21304 |hdl=10356/95416 |issn=1532-2890|hdl-access=free }}</ref>

In April 2011, a study was published by Adam Brown of [[Brigham Young University]] in the journal ''[[PS Political Science & Politics]]'' which examined "thousands of Wikipedia articles about candidates, elections, and officeholders". The study found that while the information in these articles tended to be accurate, the articles examined contained many errors of omission.<ref>{{cite journal|last1=Brown|first1=Adam R.|title=Wikipedia as a Data Source for Political Scientists: Accuracy and Completeness of Coverage|journal=PS: Political Science & Politics|date=April 8, 2011|volume=44|issue=2|pages=339–343|doi=10.1017/S1049096511000199|s2cid=154963796}}</ref>

A 2012 study co-authored by [[Shane Greenstein]] examined a decade of Wikipedia articles on United States politics and found that the more contributors there were to a given article, the more neutral it tended to be, in line with a narrow interpretation of [[Linus's law]].<ref>{{cite journal | doi=10.3386/w18167 | title=Collective Intelligence and Neutral Point of View: The Case of Wikipedia | journal=NBER Working Paper No. 18167 | date=June 2012 | last1=Greenstein | first1=Shane | last2=Zhu | first2=Feng | doi-access=free }}</ref>

Reavley et al. (2012) compared the quality of articles on select [[mental disorder|mental health]] topics on Wikipedia with corresponding articles in ''Encyclopædia Britannica'' and a psychiatry textbook. They asked experts to rate article content with regard to accuracy, up-to-dateness, breadth of coverage, referencing and readability. Wikipedia scored highest on all criteria except readability, and the authors concluded that Wikipedia is as good as or better than ''Britannica'' and a standard textbook.<ref name="Reavley" />

A 2014 perspective piece in the ''[[New England Journal of Medicine]]'' examined Wikipedia pages about 22 prescription drugs to determine if they had been updated to include the most recent FDA safety warnings. It found that 41%  of these pages were updated within two weeks after the warning, 23% were updated more than two weeks later, and the remaining 36% had not been updated to include the warning as of more than 1 year later as of January 2014.<ref>{{cite journal|last1=Hwang|first1=Thomas J.|last2=Bourgeois|first2=Florence T.|last3=Seeger|first3=John D.|title=Drug Safety in the Digital Age|journal=New England Journal of Medicine|date=June 26, 2014|volume=370|issue=26|pages=2460–2462|doi=10.1056/NEJMp1401767|pmid=24963564|doi-access=free}}</ref>

A 2014 study in the ''[[Journal of the American Pharmacists Association]]'' examined 19 Wikipedia articles about [[herbal supplement]]s, and concluded that all of these articles contained information about their "therapeutic uses and adverse effects", but also concluded that "several lacked information on drug interactions, pregnancy, and contraindications". The study's authors therefore recommended that patients not rely solely on Wikipedia as a source for information about the herbal supplements in question.<ref>{{cite journal|last1=Phillips|first1=Jennifer|last2=Lam|first2=Connie|last3=Palmisano|first3=Lisa|title=Analysis of the accuracy and readability of herbal supplement information on Wikipedia|journal=Journal of the American Pharmacists Association|date=July 1, 2014|volume=54|issue=4|pages=406–14|doi=10.1331/JAPhA.2014.13181|pmid=25063262}}</ref>

Another study published in 2014 in ''[[PLOS ONE]]'' found that Wikipedia's information about [[pharmacology]] was 99.7% accurate when compared to a pharmacology textbook, and that the completeness of such information on Wikipedia was 83.8%. The study also determined that completeness of these Wikipedia articles was lowest (68%) in the category "pharmacokinetics" and highest (91.3%) in the category "indication". The authors concluded that "Wikipedia is an accurate and comprehensive source of drug-related information for undergraduate medical education".<ref>{{cite journal|last1=Kräenbring|first1=Jona|last2=Monzon Penza|first2=Tika|last3=Gutmann|first3=Joanna|last4=Muehlich|first4=Susanne|last5=Zolk|first5=Oliver|last6=Wojnowski|first6=Leszek|last7=Maas|first7=Renke|last8=Engelhardt|first8=Stefan|last9=Sarikas|first9=Antonio|last10=Lovis|first10=Christian|title=Accuracy and Completeness of Drug Information in Wikipedia: A Comparison with Standard Textbooks of Pharmacology|journal=PLOS ONE|date=September 24, 2014|volume=9|issue=9|pages=e106930|doi=10.1371/journal.pone.0106930|pmid=25250889|pmc=4174509|bibcode=2014PLoSO...9j6930K|doi-access=free}}</ref>

=== Expert opinion ===
{{update section|The views presented here are obsolete, attitude in academia, and related studies, have shifted in the last decade, but most sources cited here are over 10 years old|date=May 2021}}

==== Librarians' views ====
In a 2004 interview with ''[[The Guardian]]'', self-described information specialist and Internet consultant<ref>Self description taken from [[blog]] biography, {{cite web| title=Phil Bradley – biography| publisher=Phil Bradley| year=2007| url=http://www.philb.com/philbiog.htm| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20071103141032/http://www.philb.com/philbiog.htm| archive-date=November 3, 2007| url-status=dead}}</ref> Philip Bradley said that he would not use Wikipedia and was "not aware of a single librarian who would". He then explained that "the main problem is the lack of authority. With printed publications, the publishers have to ensure that their data are reliable, as their livelihood depends on it. But with something like this, all that goes out the window."<ref name="Who">{{cite news| title=Who knows?| first=Simon| last=Waldman| work=[[The Guardian]]| date=October 26, 2004| access-date=February 3, 2011| url=https://www.theguardian.com/technology/2004/oct/26/g2.onlinesupplement| location=London| archive-url=https://web.archive.org/web/20140825234204/http://www.theguardian.com/technology/2004/oct/26/g2.onlinesupplement| archive-date=August 25, 2014| url-status=live| df=mdy-all}}</ref>

In 2005, the library at [[Trent University]] in [[Ontario]] stated Wikipedia had many articles that are "long and comprehensive", but that there is "a lot of room for misinformation and bias [and] a lot of variability in both the quality and depth of articles". It adds that Wikipedia has advantages and limitations, that it has "excellent coverage of technical topics" and articles are "often added quickly and, as a result, coverage of current events is quite good", comparing this to traditional sources which are unable to achieve this task. It concludes that, depending upon the need, one should think critically and assess the appropriateness of one's sources, "whether you are looking for fact or opinion, how in-depth you want to be as you explore a topic, the importance of reliability and accuracy, and the importance of timely or recent information", and adds that Wikipedia can be used in any event as a "starting point".<ref>{{cite web|date=April 30, 2007|title=About Wikipedia|url=http://www.trentu.ca/library/help/wikipedia.html|url-status=live|archive-url=https://web.archive.org/web/20051204085922/http://www.trentu.ca/library/help/wikipedia.html|archive-date=December 4, 2005|access-date=April 13, 2010|website=Trent University Library|publisher=Trent University}}</ref>

A 2006 review of Wikipedia by ''[[Library Journal]]'', using a panel of librarians, "the toughest critics of reference materials, whatever their format", asked "long standing reviewers" to evaluate three areas of Wikipedia (popular culture, current affairs, and science), and concluded: "While there are still reasons to proceed with caution when using a resource that takes pride in limited professional management, many encouraging signs suggest that (at least for now) Wikipedia may be granted the librarian's seal of approval". A reviewer who "decided to explore controversial historical and current events, hoping to find glaring abuses" said, "I was pleased by Wikipedia's objective presentation of controversial subjects" but that "as with much information floating around in cyberspace, a healthy degree of skepticism and skill at winnowing fact from opinion are required". Other reviewers noted that there is "much variation" but "good content abounds".<ref name="libraryjournal">{{cite magazine| title=I want my Wikipedia!| magazine=Library Journal| date=April 2006| url=http://lj.libraryjournal.com/2006/04/technology/i-want-my-wikipedia/| access-date=October 23, 2015| archive-url=https://web.archive.org/web/20151204024637/http://lj.libraryjournal.com/2006/04/technology/i-want-my-wikipedia| archive-date=December 4, 2015| url-status=live}}</ref>

In 2007, [[Michael Gorman (librarian)|Michael Gorman]], former president of the [[American Library Association (ALA)]] stated in an ''[[Encyclopædia Britannica]]'' blog that "A professor who encourages the use of Wikipedia is the intellectual equivalent of a dietician who recommends a steady diet of Big Macs with everything".<ref>{{cite encyclopedia|last=Gorman|first=Michael|title=Jabberwiki: The Educational Response, Part II|url=http://blogs.britannica.com/2007/06/jabberwiki-the-educational-response-part-ii/|encyclopedia=Encyclopædia Britannica Blog|publisher=Encyclopædia Britannica, Inc.|access-date=April 23, 2017|archive-url=https://web.archive.org/web/20170424015841/http://blogs.britannica.com/2007/06/jabberwiki-the-educational-response-part-ii/|archive-date=April 24, 2017|url-status=live}}</ref>

''[[Information Today]]'' (March 2006) cites librarian Nancy O'Neill (principal librarian for Reference Services at the Santa Monica Public Library System) as saying that "there is a good deal of skepticism about Wikipedia in the library community" but that "she also admits cheerfully that Wikipedia makes a good starting place for a search. You get terminology, names, and a feel for the subject."<ref name="informationtoday">{{cite web|date=March 2006|title=Wikipedia and Britannica: The kid's all right|url=http://www.infotoday.com/searcher/mar06/berinstein.shtml|url-status=live|archive-url=https://web.archive.org/web/20071104031002/http://www.infotoday.com/Searcher/mar06/berinstein.shtml|archive-date=November 4, 2007|access-date=October 31, 2007|website=Searcher|publisher=Information Today, Inc.}}</ref>

''PC Pro'' (August 2007) cites the head of the European and American Collection at the [[British Library]], Stephen Bury, as stating "Wikipedia is potentially a good thing—it provides a speedier response to new events, and to new evidence on old items". The article concludes: "For [Bury], the problem isn't so much the reliability of Wikipedia's content so much as the way in which it's used." "It's already become the first port of call for the researcher", Bury says, before noting that this is "not necessarily problematic except when they go no further". According to Bury, the trick to using Wikipedia is to understand that "just because it's in an encyclopedia (free, web or printed) doesn't mean it's true. Ask for evidence ... and contribute."<ref name="uncovered"/>

==== Articles on contentious issues ====
A 2006 article for the [[Canadian Library Association]] (CLA)<ref>{{cite Q|Q66411582}}<!-- Wikipedia Grows Up -->.</ref> discussed the Wikipedia approach, process and outcome in depth, commenting for example that in controversial topics, "what is most remarkable is that the two sides actually engaged each other and negotiated a version of the article that both can more or less live with". The author comments that:
{{blockquote|In fact Wikipedia has more institutional structure than at first appears. Some 800 experienced users are designated as administrators, with special powers of binding and loosing: they can protect and unprotect, [[Deletion of articles on Wikipedia|delete and undelete]] and revert articles, and block and unblock users. They are expected to use their powers in a neutral way, forming and implementing the consensus of the community. The effect of their intervention shows in the discussion pages of most contentious articles. Wikipedia has survived this long because it is easier to reverse vandalism than it is to commit it...}}

Shi ''et al.'' extended this analysis in discussing "The wisdom of polarized crowds" in 2017 based on [[content analysis]] of all edits to English Wikipedia articles relating to politics, social issues and science from its start to December 1, 2016.  This included almost 233,000 articles representing approximately 5 percent of the English Wikipedia. They wrote: "Political speech [at least in the United States] has become markedly more polarized in recent years ... .  [D]espite early promise of the world-wide-web to democratize access to diverse information, increased media choice and social networking platforms ... [create] echo chambers that ... degrade the quality of individual decisions, ... discount identity-incongruent opinions, stimulate and reinforce polarizing information ... foment conflict and even make communication counter-productive.  Nevertheless, a large literature documents the largely positive effect that social differences can exert on the collaborative production of information, goods and services. Research demonstrates that individuals from socially distinct groups embody diverse cognitive resources and perspectives that, when cooperatively combined ... outperform those from homogeneous groups." They translated edit histories of millions of Wikipedia editors into a 7-point political identification scale and compared that with Wikipedia's [[Template:Grading scheme|six-level article quality score (stub, start, C, B, good, featured)]] assigned via a machine learning algorithm. They found that "articles attracting more attention tend to have more balanced engagement ... [and] higher polarization is associated with higher quality."<ref>{{cite Q|Q47248083}}<!--  Shi et al. (2017) The wisdom of polarized crowds-->. They continued, "To explore whether political diversity has an upper bound beyond which polarization hampers performance, we re-estimated the regression models of quality with a quadratic polarization term. Estimates suggest that quality may eventually decline with increasing polarization, but the optimal level of polarization is above that realized by 95% of the teams in this study. For the 5% most polarized teams, there is no statistically significant pattern between polarization and quality. In other words, we do not find evidence that very high levels of political polarization hampers Wikipedia performance." (p. 11)</ref>

====Academia====
Academics have also criticized Wikipedia for its perceived failure as a reliable source and because Wikipedia editors may have no expertise, competence, or credentials in the topics on which they contribute.<ref name = Duke>{{cite web| url=http://media.www.dukechronicle.com/media/storage/paper884/news/2007/03/28/News/Several.Colleges.Push.To.Ban.Wikipedia.As.Resource-2809247.shtml|title=Several colleges push to ban Wikipedia as resource|work=Duke Chronicle|date=March 28, 2007|first=Lysa|last=Chen|archive-url=https://web.archive.org/web/20090413092513/http://media.www.dukechronicle.com/media/storage/paper884/news/2007/03/28/News/Several.Colleges.Push.To.Ban.Wikipedia.As.Resource-2809247.shtml|archive-date=April 13, 2009}}</ref><ref name="Susan_Youngwood">{{Cite news|first = Susan|last = Youngwood|title = Wikipedia: What do they know; when do they know it, and when can we trust it?|url = http://www.vermonttoday.com/apps/pbcs.dll/article?AID=/20070401/FEATURES/70330002|archive-url = https://web.archive.org/web/20161108094637/http://www.vermonttoday.com/apps/pbcs.dll/article?AID=%2F20070401%2FFEATURES%2F70330002|archive-date = November 8, 2016|work = [[Rutland Herald]]|date = April 1, 2007|quote = Perhaps the most important thing to understand about Wikipedia—both its genius and its Achilles heel—is that anyone can create or modify an entry. Anyone means your 10-year-old neighbor or a Nobel Prize winner—or an editor like me, who is itching to correct a grammar error in that Wikipedia entry that I just quoted. Entries can be edited by numerous people and be in constant flux. What you read now might change in five minutes. Five seconds, even.|access-date = May 16, 2019|url-status = live}}</ref> Adrian Riskin, a mathematician in [[Whittier College]] commented that while highly technical articles may be written by mathematicians for mathematicians, the more general maths topics, such as the article on [[polynomial]]s, are written in a very amateurish fashion with a number of obvious mistakes.<ref name=Riskin>{{cite web|last=Riskin|first=Adrian|title=Elementary Mathematics on Wikipedia|url=http://wikipediocracy.com/2013/10/20/elementary-mathematics-on-wikipedia-2/|access-date=October 24, 2013|date=October 21, 2013|archive-url=https://web.archive.org/web/20131021055906/http://wikipediocracy.com/2013/10/20/elementary-mathematics-on-wikipedia-2/|archive-date=October 21, 2013|url-status=live}}</ref>

Because Wikipedia cannot be considered a reliable source, the use of Wikipedia is not accepted in many schools and universities in writing a formal paper, and some educational institutions have banned it as a primary source while others have limited its use to only a pointer to external sources.<ref name=Duke /><ref>"[http://www.insidehighered.com/news/2007/01/26/wiki A Stand Against Wikipedia] {{Webarchive|url=https://web.archive.org/web/20120810033318/http://www.insidehighered.com/news/2007/01/26/wiki |date=2012-08-10 }}", ''Inside Higher Ed'' (January 26, 2007). Retrieved January 27, 2007.</ref><ref name=McHenry>{{Cite news|author=McHenry, Robert |date=November 15, 2004 |url=http://www.tcsdaily.com/article.aspx?id=111504A |title=The Faith-Based Encyclopedia |publisher=Tech Central Station |access-date=October 12, 2008 |author-link=Robert McHenry |url-status=dead |archive-url=https://web.archive.org/web/20060613214340/http://www.tcsdaily.com/article.aspx?id=111504A |archive-date=June 13, 2006 }}</ref> The criticism of not being a reliable source, however, may not only apply to Wikipedia but to encyclopedias in general—some university [[lecturer]]s are not impressed when students cite print-based encyclopedias in assigned work.<ref>{{cite web|url=http://www.taipeitimes.com/News/editorials/archives/2007/02/27/2003350261|title=Wikipedia on an academic hit list|first=Noam|last=Cohen|author-link = Noam Cohen|publisher=NY Times News Service|date=February 27, 2007|access-date=April 16, 2007|quote=Middlebury professor Thomas Beyer, of the Russian department, said: 'I guess I am not terribly impressed by anyone citing an encyclopedia as a reference point, but I am not against using it as a starting point.'|archive-url=https://web.archive.org/web/20070305114213/http://www.taipeitimes.com/News/editorials/archives/2007/02/27/2003350261|archive-date=March 5, 2007|url-status=live}}</ref> However, it seems that instructors have underestimated the use of Wikipedia in academia because of these concerns. Researchers and academics contend that while Wikipedia may not be used as a 100 percent accurate source for final papers, it is a valuable jumping off point for research that can lead to many possibilities if approached critically. What may be missing in academia is the emphasis on [[Critical thinking|critical analysis]] in regards to the use of Wikipedia in secondary and higher education. We should not dismiss Wikipedia entirely (there are fewer inaccuracies than there are errors of omission) but rather begin to support it, and teach the use of Wikipedia as an education tool in tandem with critical thinking skills that will allow students to filter the information found on the online encyclopedia and help them critically analyze their findings.<ref>{{cite journal | last1 = Polk | first1 = Tracy |last2 = Johnston | first2 = Melissa P. | last3 = Evers | first3 = Stephanie | year = 2015 | title = Wikipedia Use in Research: Perceptions in Secondary Schools | journal = TechTrends: Linking Research & Practice to Improve Learning | volume = 59 | issue = 3| pages = 92–102 | doi=10.1007/s11528-015-0858-6| s2cid = 62595811 }}</ref>{{Attribution needed|date=October 2024}}

An empirical study conducted in 2006 by a Business School lecturer in Information Systems at the [[University of Nottingham]],<ref>{{cite journal|url=http://firstmonday.org/htbin/cgiwrap/bin/ojs/index.php/fm/article/view/1413/1331|last=Chesney|first=Thomas|title=An empirical examination of Wikipedia's credibility|journal=First Monday|date=May 16, 2006|doi=10.5210/fm.v11i11.1413|access-date=January 20, 2010|archive-url=https://web.archive.org/web/20100411055809/http://firstmonday.org/htbin/cgiwrap/bin/ojs/index.php/fm/article/view/1413/1331|archive-date=April 11, 2010|url-status=dead |doi-access= free|url-access=subscription}}</ref> the subject of a review on the technical website ''[[Ars Technica]]'',<ref>Study cited in {{cite web| title=Experts rate Wikipedia's accuracy higher than non-experts| publisher='Ars Technica| date=November 27, 2006| url=https://arstechnica.com/news.ars/post/20061127-8296.html| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20071105210223/http://arstechnica.com/news.ars/post/20061127-8296.html| archive-date=November 5, 2007| url-status=live| df=mdy-all}}</ref> involving 55 academics asked to review specific Wikipedia articles that either were in their expert field (group 1) or chosen at random (group 2), concluded that: "The experts found Wikipedia's articles to be more credible than the non-experts. This suggests that the accuracy of Wikipedia is high. However, the results should not be seen as support for Wikipedia as a totally reliable resource as, according to the experts, 13 percent of the articles contain mistakes (10% of the experts reported factual errors of an unspecified degree, 3% of them reported spelling errors)."<ref>The study explains that "In the survey, all respondents under Condition 1 were asked if there were any mistakes in the article they had been asked to read. Only five reported seeing mistakes and one of those five reported spelling mistakes rather than factual errors. This suggests that 13 percent of Wikipedia's articles have errors." Thus 80% of the 13% related to factual errors and 20% of the 13% related to spelling errors. {{cite journal|url=http://firstmonday.org/htbin/cgiwrap/bin/ojs/index.php/fm/article/view/1413/1331|title=An empirical examination of Wikipedia's credibility|author=Chesney, Thomas|journal=First Monday|date=May 16, 2006|doi=10.5210/fm.v11i11.1413|access-date=January 20, 2010|archive-url=https://web.archive.org/web/20100411055809/http://firstmonday.org/htbin/cgiwrap/bin/ojs/index.php/fm/article/view/1413/1331|archive-date=April 11, 2010|url-status=dead |doi-access= free|url-access=subscription}}</ref>

The Gould Library at [[Carleton College]] in [[Minnesota]] has a web page describing the use of Wikipedia in academia. It asserts that "Wikipedia is without question a valuable and informative resource", but that "there is an inherent lack of reliability and stability" to its articles, again drawing attention to similar advantages and limitations as other sources. As with other reviews, it comments that one should assess one's sources and what is desired from them, and that "Wikipedia may be an appropriate resource for some assignments, but not for others." It cited Wikipedia co-founder [[Jimmy Wales]]' view that Wikipedia may not be ideal as a source for all academic uses, and (as with other sources) suggests that at the least, one strength of Wikipedia is that it provides a good starting point for current information on a very wide range of topics.<ref>{{cite web| title=Using Wikipedia| first=Matt| last=Bailey| publisher=Lawrence McKinley Gould Library, Carleton College| date=October 2, 2007| url=http://apps.carleton.edu/campus/library/for_faculty/faculty_find/wikipedia/| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20071103095446/http://apps.carleton.edu/campus/library/for_faculty/faculty_find/wikipedia/| archive-date=November 3, 2007| url-status=dead| df=mdy-all}}</ref>

In 2007, the ''[[Chronicle of Higher Education]]'' published an article written by [[Cathy Davidson]], Professor of Interdisciplinary Studies and English at [[Duke University]], in which she asserts that Wikipedia should be used to teach students about the concepts of reliability and credibility.<ref>{{cite journal |title= We Can't Ignore the Influence of Digital Technologies |journal= The Chronicle of Higher Education |publisher= Chronicle of Higher Education |date= March 23, 2007 |url= http://chronicle.com/article/We-Can-t-Ignore-the-Influence/1762 |access-date= December 15, 2015 |archive-url= https://web.archive.org/web/20160116210930/http://chronicle.com/article/We-Can-t-Ignore-the-Influence/1762 |archive-date= January 16, 2016 |url-status= live |df= mdy-all }}</ref>

In 2008, [[Hamlet Isakhanli]], founder and president of [[Khazar University]], compared the ''Encyclopædia Britannica'' and English Wikipedia articles on [[Azerbaijan]] and related subjects. His study found that Wikipedia covered the subject much more widely, more accurately and in more detail, though with some lack of balance, and that Wikipedia was the best source for the first approximation.<ref>What is Happening in the Educational System of the Contemporary World and How "The State Program on Reforms of the Higher Education System in the Republic of Azerbaijan for the Period of 2008–2012" May Best be Carried Out (in Azeri). Khazar University Press, 2008</ref>

In 2011, Karl Kehm, associate professor of physics at [[Washington College]], said: "I do encourage [my students] to use [Wikipedia] as one of many launch points for pursuing original source material. The best Wikipedia entries are well researched with extensive citations".<ref name="Burnsed">{{cite news |last1=Burnsed |first1=Brian |title=Wikipedia Gradually Accepted in College Classrooms |url=https://www.usnews.com/education/best-colleges/articles/2011/06/20/wikipedia-gradually-accepted-in-college-classrooms |access-date=June 2, 2018 |work=[[U.S. News & World Report]] |date=June 20, 2011 |archive-url=https://web.archive.org/web/20180612212951/https://www.usnews.com/education/best-colleges/articles/2011/06/20/wikipedia-gradually-accepted-in-college-classrooms |archive-date=June 12, 2018 |url-status=live  }}</ref>

Some academic journals do refer to Wikipedia articles, but are not elevating it to the same level as traditional references. For instance, Wikipedia articles have been referenced in "enhanced perspectives" provided on-line in the journal ''[[Science (journal)|Science]]''. The first of these perspectives to provide a hyperlink to Wikipedia was "A White Collar Protein Senses Blue Light" in 2002,<ref>{{cite journal|author=Linden, Hartmut|date=August 2, 2002|title=A White Collar Protein Senses Blue Light|journal=[[Science (journal)|Science]]|doi=10.1126/science.1075485|volume=297|issue=5582|pages=777–778|pmid=12161636|s2cid=41282143}} (subscription access only)</ref> and dozens of enhanced perspectives have provided such links since then. The publisher of ''Science'' states that these enhanced perspectives "include hypernotes—which link directly to websites of other relevant information available online—beyond the standard bibliographic references".<ref>{{cite web|url=http://www.aaas.org/publications/books_reports/CCLI/PDFs/01_D_Perspectives.pdf|title=Perspectives from AAAS|publisher=American Association for the Advancement of Science|first1=Yolanda S.|last1=George|first2=Shirley S.|last2=Malcolm|name-list-style=amp|access-date=October 27, 2007|archive-url=https://web.archive.org/web/20071029115643/http://www.aaas.org/publications/books_reports/CCLI/PDFs/01_D_Perspectives.pdf|archive-date=October 29, 2007|url-status=dead}}</ref>

Sverrir Steinsson{{who|date=November 2023}} investigated factors that influenced the credibility of English Wikipedia in 2023, and found that "Wikipedia transformed from a dubious source of information in its early years to an increasingly reliable one over time."<ref name="Steinsson_3/9/2023">{{cite journal | last=Steinsson | first=Sverrir | title=Rule Ambiguity, Institutional Clashes, and Population Loss: How Wikipedia Became the Last Good Place on the Internet | journal=[[American Political Science Review]] | publisher=[[Cambridge University Press]] | date=March 9, 2023 | volume=118 | issn=0003-0554 | doi=10.1017/s0003055423000138 | pages=235–251| s2cid=257434844 | doi-access=free }}</ref> This was due to it becoming "an active fact-checker and anti-fringe",<ref name="ShahBano_Ijaz_5/29/2023" /> with "pro-fringe editors" leaving the site as the Wikipedia community changed its interpretation of the NPOV policy and began to more accurately label misleading content as pseudoscience, conspiracy theory, etc., in harmony with the citations used to source that content.<ref name="ShahBano_Ijaz_5/29/2023">{{cite web | last=ShahBano Ijaz | first=Syeda | title=How Conflicts and Population Loss Led to the Rise of English Wikipedia's Credibility | website=Political Science Now | date=May 29, 2023 | url=https://politicalsciencenow.com/how-conflicts-and-population-loss-led-to-the-rise-of-english-wikipedias-credibility/ | access-date=June 20, 2023}}</ref> This reinterpretation of NPOV "had meaningful consequences, turning an organization that used to lend credence and false balance to pseudoscience, conspiracy theories, and extremism into a proactive debunker, fact-checker and identifier of fringe discourse."<ref name="Steinsson_3/9/2023" />

Educational and cognitive psychologist [[Sam Wineburg]] said in 2024 that "No, Wikipedia isn’t an unreliable source that anyone can edit and that should be avoided. In 2024, it has become a remarkably rigorous self-correcting resource that all of us should be using more often."<ref name="The Boston Globe 17 October 2024">{{cite news |last1=Wineburg |first1=Sam |last2=Ziv |first2=Nadav |title=Go ahead and use Wikipedia for research - The Boston Globe |url=https://www.bostonglobe.com/2024/10/17/opinion/use-wikipedia-reliable-source/ |access-date=18 October 2024 |work=[[The Boston Globe]] |date=17 October 2024}}</ref>
<!--The academic world's view of Wikipedia has improved during the last few years, as can be inferred from the increase in the number of citations in international scientific journals. A search in the ''[[ScienceDirect]]'' database (a large online collection of published scientific research produced by [[Elsevier]]) for academic and scientific journal articles citing Wikipedia in their references, yields the following result to June 5, 2010:<ref>{{cite journal | title=ScienceDirect Indexed Papers| publisher=ScienceDirect| date=Various dates| url=http://www.sciencedirect.com/science?_ob=ArticleListURL&_method=list&_ArticleListID=1359637889&_sort=r&_st=4&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=7fea708946cfc13e05e816774d4a4093 | access-date=June 5, 2010 }}</ref>

{|class="wikitable"
|-
!Year article published
!No. of articles citing Wikipedia
|-style="text-align:center;"
|Before 2003
|0
|-style="text-align:center;"
|2003
|1
|-style="text-align:center;"
|2004
|9
|-style="text-align:center;"
|2005
|31
|-style="text-align:center;"
|2006
|133
|-style="text-align:center;"
|2007
|330
|-style="text-align:center;"
|2008
|451
|-style="text-align:center;"
|2009
|614
|-style="text-align:center;"
|2010 (as of June 5)
|478
|}
-->

==== Journalism and use of Wikipedia in the newsroom ====
In his 2014 book ''Virtual Unreality'', [[Charles Seife]], a professor of journalism at [[New York University]], noted Wikipedia's susceptibility to hoaxes and misinformation, including manipulation by commercial and political organizations "masquerading as common people" making edits to Wikipedia. In conclusion, Seife presented the following advice:<ref name="Seife2014" />

{{blockquote|Wikipedia is like an old and eccentric uncle.

He can be a lot of fun—over the years he's seen a lot, and he can tell a great story. He's also no dummy; he's accumulated a lot of information and has some strong opinions about what he's gathered. You can learn quite a bit from him. But take everything he says with a grain of salt. A lot of the things he thinks he knows for sure aren't quite right or are taken out of context. And when it comes down to it, sometimes he believes things that are a little bit, well, nuts.

If it ever matters to you whether something he said is real or fictional, it's crucial to check it out with a more reliable source.<ref name="Seife2014">{{cite book|first=Charles|last=Seife|title=Virtual Unreality: Just Because the Internet Told You, how Do You Know It's True?|url=https://books.google.com/books?id=cePyngEACAAJ|year=2014|publisher=Penguin Publishing Group|isbn=978-0-670-02608-1|pages=26–29, 32–34, 201|access-date=2017-06-04|archive-url=https://web.archive.org/web/20190331231601/https://books.google.com/books?id=cePyngEACAAJ|archive-date=2019-03-31|url-status=live}}</ref>}}

Seife observed that when false information from Wikipedia spreads to other publications, it sometimes alters truth itself.<ref name="Seife2014" /> On June 28, 2012, for example, an anonymous Wikipedia contributor added the invented nickname "Millville Meteor" to the Wikipedia biography of baseball player [[Mike Trout]]. A couple of weeks later, a ''[[Newsday]]'' sports writer reproduced the nickname in an article, and "with that act, the fake nickname became real".<ref name="Seife2014" /> Seife pointed out that while Wikipedia, by some standards, could be described as "roughly as accurate" as traditional publications, and is more up to date, "there's a difference between the kind of error one would find in Wikipedia and what one would in ''Britannica'' or ''Collier's'' or even in the now-defunct Microsoft Encarta encyclopedia ... the majority of hoaxes on Wikipedia could never have appeared in the old-fashioned encyclopedias."<ref name="Seife2014" /> [[Dwight Garner (critic)|Dwight Garner]], reviewing Seife's book in ''[[The New York Times]]'', said that he himself had "been burned enough times by bad online information", including "Wikipedia howlers", to have adopted a very sceptical mindset.<ref>{{cite news|url=https://www.nytimes.com/2014/07/02/books/in-virtual-unreality-charles-seife-unfriends-gullibility.html|title=Online, the Lying Is Easy. In 'Virtual Unreality,' Charles Seife Unfriends Gullibility|last=Garner|first=Dwight|work=The New York Times|date=July 1, 2014|access-date=June 4, 2017|archive-url=https://web.archive.org/web/20170901155326/https://www.nytimes.com/2014/07/02/books/in-virtual-unreality-charles-seife-unfriends-gullibility.html|archive-date=September 1, 2017|url-status=live}}</ref>

In November 2012, judge [[Brian Leveson]] was accused of having forgotten "one of the elementary rules of journalism" when he named a "Brett Straub" as one of the founders of ''[[The Independent]]'' newspaper in [[Leveson report|his report on the culture, practices and ethics of the British press]]. The name had been added to the Wikipedia article on ''The Independent'' over a year prior, and turned out to be that of a 25-year-old Californian, whose friend had added his name to a string of Wikipedia pages as a prank.<ref>{{cite news | url = https://www.independent.co.uk/news/media/press/levesons-wikipedia-moment-how-internet-research-on-the-independents-history-left-him-redfaced-8372446.html | last = McSmith | first = Andy | title = Leveson's Wikipedia moment: how internet 'research' on The Independent's history left him red-faced | work = The Independent | date = November 30, 2012 | access-date = March 25, 2014 | archive-url = https://web.archive.org/web/20121204151536/http://www.independent.co.uk/news/media/press/levesons-wikipedia-moment-how-internet-research-on-the-independents-history-left-him-redfaced-8372446.html | archive-date = December 4, 2012 | url-status = live }}</ref> Straub was tracked down by ''The Telegraph'' and commented, "The fact someone, especially a judge, has believed something on Wikipedia is kind of shocking. My friend went on and edited a bunch of Wikipedia pages and put my name there. [...] I knew my friend had done it but I didn't know how to change them back and I thought someone would. At one point I was the creator of Coca-Cola or something. You know how easy it is to change Wikipedia. Every time he came across a red linked name he put my name in its place."<ref>{{cite news | url = https://www.telegraph.co.uk/news/uknews/leveson-inquiry/9723296/Wikipedia-the-25-year-old-student-and-the-prank-that-fooled-Leveson.html | last = Allen | first = Nick | title = Wikipedia, the 25-year–old student and the prank that fooled Leveson | work = The Telegraph | date = December 5, 2012 | access-date = March 25, 2014 | archive-url = https://web.archive.org/web/20140131162315/http://www.telegraph.co.uk/news/uknews/leveson-inquiry/9723296/Wikipedia-the-25-year-old-student-and-the-prank-that-fooled-Leveson.html | archive-date = January 31, 2014 | url-status = live }}</ref>

A 2016 [[BBC]] article by Ciaran McCauley similarly noted that "plenty of mischievous, made-up information has found its way" on to Wikipedia and that "many of these fake facts have fallen through the cracks and been taken as gospel by everyone from university academics to major newspapers and broadcasters."<ref name=McCauleyBBC /> Listing examples of journalists being embarrassed by reproducing hoaxes and other falsifications from Wikipedia in their writing, including false information propagated by major news organizations in their obituaries of [[Maurice Jarre]] and [[Ronnie Hazlehurst]], McCauley stated: "Any journalist in any newsroom will likely get a sharp slap across the head from an editor for treating Wikipedia with anything but total skepticism (you can imagine the kicking I've taken over this article)."<ref name=McCauleyBBC>{{cite news|last=McCauley|first=Ciaran|url=https://www.bbc.co.uk/news/uk-northern-ireland-37523772|title=Wikipedia hoaxes: From Breakdancing to Bilcholim|publisher=BBC|date=February 8, 2017|access-date=June 4, 2017|archive-url=https://web.archive.org/web/20170520210800/http://www.bbc.co.uk/news/uk-northern-ireland-37523772|archive-date=May 20, 2017|url-status=live}}</ref>

The ''[[Daily Mail]]''—itself banned as a source on Wikipedia in 2017 because of its perceived unreliability—has publicly stated that it "banned all its journalists from using Wikipedia as a sole source in 2014 because of its unreliability".<ref>{{cite news|last=Jackson|first=Jasper|title=Wikipedia bans Daily Mail as 'unreliable' source|url=https://www.theguardian.com/technology/2017/feb/08/wikipedia-bans-daily-mail-as-unreliable-source-for-website|work=The Guardian|date=October 3, 2016|access-date=June 4, 2017|archive-url=https://web.archive.org/web/20190118191343/https://www.theguardian.com/technology/2017/feb/08/wikipedia-bans-daily-mail-as-unreliable-source-for-website|archive-date=January 18, 2019|url-status=live}}</ref>

''[[Slate (magazine)|Slate]]'' said in 2022 that "Screenshots of vandalized Wikipedia articles, even when reverted within minutes, often have a much longer afterlife in news reports and on social media, creating the public impression that the platform is more vulnerable to abuse than it actually is."<ref>{{cite web |last1=Breslow |first1=Samuel |title=How a False Claim About Wikipedia Sparked a Right-Wing Media Frenzy |url=https://slate.com/technology/2022/08/wikipedia-recession-article.html |website=Slate Magazine |access-date=September 1, 2022 |language=en |date=August 11, 2022 |archive-date=January 22, 2023 |archive-url=https://web.archive.org/web/20230122103526/https://slate.com/technology/2022/08/wikipedia-recession-article.html |url-status=live }}</ref>

==== Science and medicine ====
{{main|Health information on Wikipedia|Science information on Wikipedia}}
Science and medicine are areas where accuracy is of high importance and [[peer review]] is the norm. While some of Wikipedia's content has passed a form of peer review, most has not.<ref>{{cite journal|last1=Heilman|first1=JM|last2=Kemmann|first2=E|last3=Bonert|first3=M|last4=Chatterjee|first4=A|last5=Ragar|first5=B|last6=Beards|first6=GM|last7=Iberri|first7=DJ|last8=Harvey|first8=M|last9=Thomas|first9=B|last10=Stomp|first10=W|last11=Martone|first11=MF|last12=Lodge|first12=DJ|last13=Vondracek|first13=A|last14=de Wolff|first14=JF|last15=Liber|first15=C|last16=Grover|first16=SC|last17=Vickers|first17=TJ|last18=Meskó|first18=B|last19=Laurent|first19=MR|title=Wikipedia: a key tool for global public health promotion|journal=Journal of Medical Internet Research|date=January 31, 2011|volume=13|issue=1|pages=e14|pmid=21282098|doi=10.2196/jmir.1589|pmc=3221335 |doi-access=free }}</ref>

A 2008 study examined 80 Wikipedia drug entries. The researchers found few factual errors in this set of articles, but determined that these articles were often missing important information, like [[contraindications]] and [[drug interactions]]. One of the researchers noted that "If people went and used this as a sole or authoritative source without contacting a health professional...those are the types of negative impacts that can occur." The researchers also compared Wikipedia to [[Medscape Drug Reference]] (MDR), by looking for answers to 80 different questions covering eight categories of drug information, including adverse drug events, dosages, and mechanism of action. They have determined that MDR provided answers to 82.5 percent of the questions, while Wikipedia could only answer 40 percent, and that answers were less likely to be complete for Wikipedia as well. None of the answers from Wikipedia were determined factually inaccurate, while they found four inaccurate answers in MDR. But the researchers found 48 errors of omission in the Wikipedia entries, compared to 14 for MDR. The lead investigator concluded: "I think that these errors of omission can be just as dangerous [as inaccuracies]", and he pointed out that drug company representatives have been caught deleting information from Wikipedia entries that make their drugs look unsafe.<ref name=Drug08>{{cite journal |author1=Clauson KA |author2=Polen HH |author3=[[Maged N. Kamel Boulos|Kamel Boulos MN]] |author4=Dzenowagis JH |title=Scope, completeness, and accuracy of drug information in Wikipedia |journal=Annals of Pharmacotherapy |volume=42 |issue=12 |year=2008 |pmid=19017825 |doi=10.1345/aph.1L474 |url=http://www.theannals.com/cgi/reprint/aph.1L474v1.pdf |pages=1814–21 |s2cid=2072846 |access-date=September 25, 2009 |archive-url=https://web.archive.org/web/20090325104236/http://www.theannals.com/cgi/reprint/aph.1L474v1.pdf |archive-date=March 25, 2009 }}
*{{cite news |author=Anne Harding |date=November 25, 2008 |title=Wikipedia often omits important drug information: study |work=Reuters |url=https://www.reuters.com/article/internetNews/idUSTRE4AN7BO20081125 |access-date=July 1, 2017 |archive-date=October 5, 2020 |archive-url=https://web.archive.org/web/20201005123637/https://www.reuters.com/article/internetNews/idUSTRE4AN7BO20081125 |url-status=live }}</ref>

A 2009 survey asked US toxicologists how accurately they rated the portrayal of health risks of chemicals in different media sources. It was based on the answers of 937 members of the [[Society of Toxicology]] and found that these experts regarded Wikipedia's reliability in this area as far higher than that of all traditional news media:
{{blockquote|In perhaps the most surprising finding in the entire study, all these national media outlets [U.S. newspapers, news magazines, health magazines, broadcast and cable television networks] are easily eclipsed by two representatives of "new media": [[WebMD]] and Wikipedia. WebMD is the only news source whose coverage of chemical risk is regarded as accurate by a majority (56 percent) of toxicologists, closely followed by Wikipedia's 45 percent accuracy rating. By contrast, only 15 percent describe as accurate the portrayals of chemical risk found in ''The New York Times'', Washington Post, and Wall Street Journal.<ref name=Tox09>S. Robert Lichter, Ph.D,,: [https://web.archive.org/web/20130824041907/http://stats.org/stories/2009/are_chemicals_killing_us.html Are chemicals killing us?] Statistical Assessment Service, May 21, 2009</ref>}}

In 2010 researchers compared information about 10 types of cancer on Wikipedia to similar data from the [[National Cancer Institute]]'s Physician Data Query and concluded "the Wiki resource had similar accuracy and depth to the professionally edited database" and that "sub-analysis comparing common to uncommon cancers demonstrated no difference between the two", but that ease of readability was an issue.<ref>{{cite journal|last=Rajagopalan|title=Accuracy of cancer information on the Internet: A comparison of a Wiki with a professionally maintained database|journal=Journal of Clinical Oncology|volume=28|issue=15_suppl|page=6058|year=2010|url=http://meeting.ascopubs.org/cgi/content/abstract/28/15_suppl/6058|access-date=June 5, 2010|display-authors=etal|doi=10.1200/jco.2010.28.15_suppl.6058|archive-url=https://web.archive.org/web/20140109220833/http://meeting.ascopubs.org/cgi/content/abstract/28/15_suppl/6058|archive-date=January 9, 2014|url-status=live|url-access=subscription}}</ref>

A study in 2011 came to the result that categories most frequently absent in Wikipedia's drug articles are those of drug interactions and medication use in breastfeeding.<ref name=Lavsa2011>{{Cite journal | last1 = Lavsa | first1 = S. M. | last2 = Corman | first2 = S. L. | last3 = Culley | first3 = C. M. | last4 = Pummer | first4 = T. L. | title = Reliability of Wikipedia as a medication information source for pharmacy students | doi = 10.1016/j.cptl.2011.01.007 | journal = Currents in Pharmacy Teaching and Learning | volume = 3 | issue = 2 | pages = 154–158 | year = 2011 }}</ref> Other categories with incomplete coverage were descriptions of off-label indications, contraindications and precautions, adverse drug events and dosing.<ref name=Lavsa2011/> Information most frequently deviating from other sources used in the study were that of contraindications and precautions, drug absorption and adverse drug events.<ref name=Lavsa2011/>

A 2012 study reported that Wikipedia articles about pediatric [[otolaryngology]] contained twice as many errors and omissions as the medical database [[eMedicine]].<ref>{{cite journal|last1=Volsky|first1=Peter G.|last2=Baldassari|first2=Cristina M.|last3=Mushti|first3=Sirisha|last4=Derkay|first4=Craig S.|title=Quality of Internet information in pediatric otolaryngology: A comparison of three most referenced websites|journal=International Journal of Pediatric Otorhinolaryngology|date=September 2012|volume=76|issue=9|pages=1312–1316|doi=10.1016/j.ijporl.2012.05.026|pmid=22770592}}</ref>

In a U.S. study in 2014, 10 researchers examined 10 Wikipedia health articles of the most costly medical conditions in the United States and found that 90% of the entries contained errors and statements that contradicted latest medical research. However, according to Stevie Benton of Wikimedia UK the sample size used in the research may have been too small to be considered representative.<ref>{{cite news|title=Trust your doctor, not Wikipedia, say scientists|url=https://www.bbc.com/news/health-27586356|work=BBC News|access-date=May 27, 2014|date=May 27, 2014|archive-url=https://web.archive.org/web/20140527152757/http://www.bbc.com/news/health-27586356|archive-date=May 27, 2014|url-status=live}}</ref><ref>{{cite journal|title=Wikipedia vs Peer-Reviewed Medical Literature for Information About the 10 Most Costly Medical Conditions|journal=The Journal of the American Osteopathic Association|date=May 1, 2014|volume=114|issue=5|pages=368–373|doi=10.7556/jaoa.2014.035|pmid=24778001 | last1 = Hasty | first1 = RT | last2 = Garbalosa | first2 = RC | last3 = Barbato | first3 = VA | last4 = Valdes | first4 = PJ Jr | last5 = Powers | first5 = DW | last6 = Hernandez | first6 = E | last7 = John | first7 = JS | last8 = Suciu | first8 = G | last9 = Qureshi | first9 = F | last10 = Popa-Radu | first10 = M | last11 = San Jose | first11 = S | last12 = Drexler | first12 = N | last13 = Patankar | first13 = R | last14 = Paz | first14 = JR | last15 = King | first15 = CW | last16 = Gerber | first16 = HN | last17 = Valladares | first17 = MG | last18 = Somji | first18 = AA| doi-access = free }}</ref>
Only part of the data was made public, and for two statements that were released for other researchers to examine, the claim that Wikipedia's statements were contradictory to the peer-reviewed literature was called into question.<ref>{{Cite Q | Q56888119 }}</ref> However, more open studies, published in 2017 and 2020, concluded, that Wikipedia provided less accurate medical information than paid-access online encyclopedias.<ref>Matheson, D., & Matheson-Monnet, C. (2017). Wikipedia as informal self education for clinical decision-making in medical practice. Open Medicine Journal, 4 (1), 15–25.  https://doi.org/10.2174/1874220301704010015</ref><ref>Yacob, M., Lotfi, S., Tang, S., & Jetty, P. (2020). Wikipedia in vascular surgery medical education: Comparative study. JMIR Medical Education, 6(1), e18076. https://doi.org/10.2196/18076</ref>  

A 2014 study published in ''[[PLOS One]]'' looked at the quality of Wikipedia articles on [[pharmacology]], comparing articles from English and German Wikipedia with academic textbooks. It found that "the collaborative and [[participatory design]] of Wikipedia does generate high quality information on pharmacology that is suitable for undergraduate medical education".<ref>{{Cite journal | doi = 10.1371/journal.pone.0106930| title = Accuracy and Completeness of Drug Information in Wikipedia: A Comparison with Standard Textbooks of Pharmacology| journal = PLOS ONE| volume = 9| issue = 9| pages = e106930| year = 2014| last1 = Kräenbring | first1 = J. | last2 = Monzon Penza | first2 = T. | last3 = Gutmann | first3 = J. | last4 = Muehlich | first4 = S. | last5 = Zolk | first5 = O. | last6 = Wojnowski | first6 = L. | last7 = Maas | first7 = R. | last8 = Engelhardt | first8 = S. | last9 = Sarikas | first9 = A. | pmid=25250889 | pmc=4174509
| bibcode = 2014PLoSO...9j6930K| doi-access = free}}</ref>

A 2024 review of online information sources for healthcare-related research cautioned against using Wikipedia as a primary reference, and noted its value as a resource to identify sources of information.<ref>Banchik LH, Gray B. What happened to my Index Medicus? Nutr Clin Pract. 2024 Aug;39(4):743-750. doi: 10.1002/ncp.11173. Epub 2024 Jun 12. PMID: 38864650.</ref> Jarry said in 2024 that evaluating Wikipedia's reliability on medicine or any subject is challenging and that researchers "have to pick a sample and hope it is representative," saying also that "Wikipedia, overall, has no business being this good."<ref name="Can You Trust Dr. Wikipedia? 2024" />

==== Judiciary ====
References to Wikipedia in United States judicial opinions have increased each year since 2004. In a 2017 ruling, the [[Supreme Court of Texas]] advised against reliance on the information in Wikipedia for judicial rulings, arguing that its lack of reliability prevents using it as a source of authority in legal opinions.<ref>{{cite web |last1=Volokh |first1=Eugene |author1-link=Eugene Volokh |title=When should courts rely on Wikipedia? |url=https://reason.com/volokh/2017/03/17/when-should-courts-rely-on-wik/ |publisher=Reason |date=March 17, 2017 |access-date=August 21, 2021 |archive-date=August 21, 2021 |archive-url=https://web.archive.org/web/20210821011846/https://reason.com/volokh/2017/03/17/when-should-courts-rely-on-wik/ |url-status=live }}</ref><ref>{{cite web|author=Texas Supreme Court|title=D Magazine Partners v. Rosenthal|url=http://www.txcourts.gov/media/1437551/150790.pdf|access-date=August 21, 2021|archive-date=June 29, 2021|archive-url=https://web.archive.org/web/20210629172812/http://www.txcourts.gov/media/1437551/150790.pdf|url-status=live}}</ref>

The Supreme Court of India in its judgment in ''Commr. of Customs, Bangalore vs. ACER India Pvt.'' (Citation 2007(12)SCALE581) held that "We have referred to Wikipedia, as the learned Counsel for the parties relied thereupon. It is an online encyclopaedia and information can be entered therein by any person and as such it may not be authentic."<ref>Sinham, B. [http://www.judis.nic.in/supremecourt/qrydisp.aspx?filename=29717 Appeal (civil) 2321 of 2007] {{Webarchive|url=https://web.archive.org/web/20090410103840/http://judis.nic.in/supremecourt/qrydisp.aspx?filename=29717 |date=April 10, 2009 }}. [[Supreme Court of India]].</ref>

====Editors of ''Encyclopædia Britannica''====
In a 2004 piece called "The Faith-Based Encyclopedia", [[Robert McHenry]], a former editor-in-chief of ''[[Encyclopædia Britannica]]'', stated that Wikipedia errs in billing itself as an encyclopedia, because that word implies a level of authority and accountability that he believes cannot be possessed by an openly editable reference. McHenry argued that "the typical user doesn't know how conventional encyclopedias achieve reliability, only that they do".<ref name="faith-based encyc"/> He added:
{{blockquote|[H]owever closely a Wikipedia article may at some point in its life attain to reliability, it is forever open to the uninformed or semiliterate meddler... The user who visits Wikipedia to learn about some subject, to confirm some matter of fact, is rather in the position of a visitor to a public restroom. It may be obviously dirty, so that he knows to exercise great care, or it may seem fairly clean, so that he may be lulled into a false sense of security. What he certainly does not know is who has used the facilities before him."<ref name="faith-based encyc">{{cite web|title=The Faith-Based Encyclopedia |first=Robert |last=McHenry |work=[[Tech Central Station]] |date=November 15, 2004 |url=http://www.tcsdaily.com/article.aspx?id=111504a |access-date=2007-10-31 |url-status=dead |archive-url=https://web.archive.org/web/20060613214340/http://www.tcsdaily.com/article.aspx?id=111504A |archive-date=June 13, 2006 |author-link=Robert McHenry }}</ref>}}
Similarly, ''Britannica''{{'}}s executive editor, [[Ted Pappas]], was quoted in ''[[The Guardian]]'' as saying:
{{blockquote|The premise of Wikipedia is that continuous improvement will lead to perfection. That premise is completely unproven.<ref name="Who" />}}

In the September 12, 2006, edition of ''[[The Wall Street Journal]]'', Jimmy Wales debated with [[Dale Hoiberg]], editor-in-chief of ''[[Encyclopædia Britannica]]''. Hoiberg focused on a need for expertise and control in an encyclopedia and cited [[Lewis Mumford]] that overwhelming information could "bring about a state of intellectual enervation and depletion hardly to be distinguished from massive ignorance". Wales emphasized Wikipedia's differences, and asserted that openness and transparency lead to quality. Hoiberg replied that he "had neither the time nor space to respond to [criticisms]" and "could corral any number of links to articles alleging errors in Wikipedia", to which Wales responded: "No problem! Wikipedia to the rescue with a fine article", and included a link to the Wikipedia article ''[[Criticism of Wikipedia]]''.<ref name="wsj9-12-2006">{{Cite news |url=https://www.wsj.com/articles/SB115756239753455284 |title=The Wall Street Journal Online |access-date=September 13, 2006 |date=September 12, 2006 |archive-url=https://web.archive.org/web/20170809170821/https://www.wsj.com/articles/SB115756239753455284 |archive-date=August 9, 2017 |url-status=live }}</ref>

=== Tools for testing the reliability of articles ===
[[File:014-WW-Screenshot-Reliability of Wikipedia.png|thumb|Screenshot of Wiki-Watch rating of the article ''Reliability of Wikipedia'' rated as ''reliable source'' and additional orange WikiTrust marks for questionable edits]]
While experienced editors can view the article history and discussion page, for normal users it is not so easy to check whether information from Wikipedia is reliable. University projects from California, Switzerland and Germany try to improve that by methods of formal analysis and data mining. [[Wiki-Watch]] from Germany, which was inspired by the [[WikiBu]] from [[Switzerland]], shows an evaluation up to five-stars for every English or German article in Wikipedia. Part of this rating is the tool [[WikiTrust]] which shows the trustworthiness of single text parts of Wikipedia articles by white (trustworthy) or orange (not trustworthy) markings.<ref>Selena Mann: ''[http://www.itworldcanada.com/blogs/cooltools/2011/01/14/new-tool-used-to-evaluate-wikipedia/55979/ New tool used to evaluate Wikipedia.] {{Webarchive|url=https://web.archive.org/web/20110611194514/http://www.itworldcanada.com/blogs/cooltools/2011/01/14/new-tool-used-to-evaluate-wikipedia/55979/ |date=June 11, 2011 }}'' In: it-World Canada. January 14, 2011.</ref>

== Information loop ==
{{main|Circular reporting}}
[[File:Relationship between Wikipedia and the press.svg|thumb|A diagram of citogenesis]]
[[Wikipedia:Verifiability#Reliable sources|Sources accepted as reliable for Wikipedia]] may rely on Wikipedia as a reference source, sometimes indirectly. If the original information in Wikipedia was false, once it has been reported in sources considered reliable, Wikipedia can use them to reference the false information, giving an apparent credibility to falsehood. This in turn increases the likelihood of the false information being reported in other media.<ref>Metz, Cade. [https://www.theregister.co.uk/2009/01/26/britannica_slaps_google/ "Google and the Great Wikipedia Feedback Loop"] {{Webarchive|url=https://web.archive.org/web/20170810170157/https://www.theregister.co.uk/2009/01/26/britannica_slaps_google/ |date=August 10, 2017 }}, ''[[The Register]]'', January 26, 2009</ref> A known example is the [[Sacha Baron Cohen]] article, where false information added in Wikipedia was apparently used by two newspapers, leading to it being treated as reliable in Wikipedia.<ref>{{cite web |author=lantrix |url=http://techdebug.com/blog/2008/04/19/wikipedia-article-creates-circular-references/ |title=Article on Sacha Baron Cohen feedback loop |publisher=Techdebug.com |date=April 19, 2008 |access-date=March 19, 2012 |archive-url=https://web.archive.org/web/20120323174743/http://techdebug.com/blog/2008/04/19/wikipedia-article-creates-circular-references/ |archive-date=March 23, 2012 |url-status=live }}</ref>{{Better source needed|reason=The current source is a self-published blog ([[WP:NOTRS]]).|date=June 2024}} This process of creating reliable sources for false facts has been termed "citogenesis" by ''[[xkcd]]'' [[webcomic]] artist [[Randall Munroe]].<ref>{{cite web|url=http://www.xkcd.com/978/ |title=Citogenesis |first=Randall |last=Munroe |author-link=Randall Munroe |publisher=xkcd |archive-url=https://web.archive.org/web/20111118010341/http://xkcd.com/978 |archive-date=November 18, 2011}}</ref><ref>{{cite web |url=http://neologisms.rice.edu/index.php?a=term&d=1&t=15989 |title=Citogenesis – Neologisms |publisher=rice university |access-date=June 7, 2014 |archive-url=https://web.archive.org/web/20140814100007/http://neologisms.rice.edu/index.php?a=term&d=1&t=15989 |archive-date=August 14, 2014 |url-status=live }}</ref><ref>{{cite web |url=http://lemire.me/blog/archives/2012/01/27/citogenesis-in-science-and-the-importance-of-real-problems/ |title=Citogenesis in science and the importance of real problems |first=Daniel |last=Lemire |date=January 27, 2012 |access-date=June 7, 2014 |archive-url=https://web.archive.org/web/20140528030019/http://lemire.me/blog/archives/2012/01/27/citogenesis-in-science-and-the-importance-of-real-problems/ |archive-date=May 28, 2014 |url-status=live }}</ref>

== Propagation of misinformation ==
{{Update|section|date=March 2022}}
Somewhat related to the "information loop" is the propagation of misinformation to other websites (Answers.com is just one of many) which will often quote misinformation from Wikipedia verbatim, and without mentioning that it has come from Wikipedia. A piece of misinformation originally taken from a Wikipedia article will live on in perhaps dozens of other websites, even if Wikipedia itself has deleted the unreliable material.<ref name="Rosenzweig2011">{{cite book|last=Rosenzweig|first=Roy|author-link=Roy Rosenzweig|title=Clio Wired: The Future of the Past in the Digital Age|url=https://books.google.com/books?id=4nivoPD7L40C&pg=PT97|year=2011|publisher=Columbia University Press|location=New York|isbn=978-0-231-15085-9|access-date=September 25, 2016|archive-url=https://web.archive.org/web/20190331142903/https://books.google.com/books?id=4nivoPD7L40C&pg=PT97|archive-date=March 31, 2019|url-status=live}} page 71.</ref>

=== Other ===
In one article, ''Information Today'' (March 2006) likens<ref name="informationtoday" /> comparisons between Wikipedia and ''Britannica'' to "[[apples and oranges]]":
{{blockquote|Even the revered ''Encyclopædia Britannica'' is riddled with errors, not to mention the subtle yet pervasive biases of individual subjectivity and corporate correctness... There is no one perfect way. Britannica seems to claim that there is. Wikipedia acknowledges there's no such thing. Librarians and information professionals have always known this. That's why we always consult multiple sources and counsel our users to do the same.}}

[[Andrew Orlowski]], a columnist for ''[[The Register]]'', expressed similar criticisms in 2005, writing that the use of the term "encyclopedia" to describe Wikipedia may lead users into believing it is more reliable than it may be.<ref>{{cite web|url=https://www.theregister.co.uk/2005/12/12/wikipedia_no_responsibility/page2.html|title=Who's responsible for Wikipedia?|last=Orlowski|first=Andrew|date=December 12, 2005|quote=The public has a firm idea of what an 'encyclopedia' is, and it's a place where information can generally be trusted, or at least slightly more trusted than what a labyrinthine, mysterious bureaucracy can agree upon, and surely more trustworthy than a piece of spontaneous graffiti—and Wikipedia is a king-sized cocktail of the two.|work=The Register|access-date=June 30, 2009|archive-url=https://web.archive.org/web/20090206173014/http://www.theregister.co.uk/2005/12/12/wikipedia_no_responsibility/page2.html|archive-date=February 6, 2009|url-status=live}}</ref>

[[BBC]] [[technology]] specialist [[Bill Thompson (technology writer)|Bill Thompson]] wrote that "Most Wikipedia entries are written and submitted in good faith, and we should not let the contentious areas such as politics, religion or biography shape our view of the project as a whole", that it forms a good starting point for serious research but that:<ref name=Thompson>{{cite news| title=What is it with Wikipedia?| first=Bill| last=Thompson| publisher=BBC| date=December 16, 2005| url=http://news.bbc.co.uk/1/hi/technology/4534712.stm| access-date=October 31, 2007| author-link=Bill Thompson (technology writer)| archive-url=https://web.archive.org/web/20070816075532/http://news.bbc.co.uk/1/hi/technology/4534712.stm| archive-date=August 16, 2007| url-status=live}}</ref>
{{blockquote|No information source is guaranteed to be accurate, and we should not place complete faith in something which can so easily be undermined through malice or ignorance... That does not devalue the project entirely, it just means that we should be skeptical about Wikipedia entries as a primary source of information... It is the same with search engine results. Just because something comes up in the top 10 on [[MSN Search]] or [[Google]] does not automatically give it credibility or vouch for its accuracy or importance.<ref name=Thompson/>}}
Thompson adds the observation that since most popular online sources are inherently unreliable in this way, one byproduct of the [[information age]] is a wiser audience who are learning to check information rather than take it on faith due to its source, leading to "a better sense of how to evaluate information sources".<ref name=Thompson/>

In his 2007 ''Guide to Military History on the Internet'', [[Simon Fowler (author)|Simon Fowler]] rated Wikipedia as "the best general resource" for military history research, and stated that "the results are largely accurate and generally free of bias".<ref>[[Simon Fowler (author)|Fowler, Simon]] ''Guide to Military History on the Internet'', UK:Pen & Sword, {{ISBN|978-1-84415-606-1}}, p. 7</ref> When rating Wikipedia as the No. 1 military site he mentioned that "Wikipedia is often criticised for its inaccuracy and bias, but in my experience the military history articles are spot on."<ref>[[Simon Fowler (author)|Fowler, Simon]] ''Guide to Military History on the Internet'', UK:Pen & Sword, {{ISBN|978-1-84415-606-1}}, p. 201</ref>

In July 2008, ''[[The Economist]]'' magazine described Wikipedia as "a user-generated reference service" and noted that Wikipedia's "elaborate moderation rules put a limit to acrimony" generated by cyber-nationalism.<ref>{{cite news |url=http://www.economist.com/world/international/displayStory.cfm?source=hptextfeature&story_id=11792535 |title=Cyber-nationalism &#124; The brave new world of e-hatred |newspaper=The Economist |date=July 24, 2008 |access-date=April 13, 2010 |archive-url=https://web.archive.org/web/20091201134023/http://www.economist.com/world/international/displayStory.cfm?source=hptextfeature&story_id=11792535 |archive-date=December 1, 2009 |url-status=live }}</ref>

Jimmy Wales, a co-founder of Wikipedia, stresses that encyclopedias of any type are not usually appropriate as primary sources, and should not be relied upon as being authoritative.<ref name="AWorkInProgress">[http://www.businessweek.com/technology/content/dec2005/tc20051214_441708.htm Wikipedia: "A Work in Progress"] {{Webarchive|url=https://web.archive.org/web/20120421000522/http://www.businessweek.com/technology/content/dec2005/tc20051214_441708.htm |date=April 21, 2012 }}, ''[[BusinessWeek]]'' (December 14, 2005). Retrieved January 29, 2007.</ref>

[[Carnegie Mellon University|Carnegie Mellon]] Professor [[Randy Pausch]] offered the following anecdote in his book ''[[The Last Lecture]]''. He was surprised that his entry to ''[[World Book Encyclopedia]]'' on virtual reality was accepted without question, so he concluded, "I now believe Wikipedia is a perfectly fine source for your information, because I know what the quality control is for real encyclopedias."<ref name="Pausch2008">{{cite book|first=Randy|last=Pausch|title=The Last Lecture|url=https://books.google.com/books?id=mVqZAAAAQBAJ&pg=PT42|date=April 8, 2008|publisher=Hachette Books|isbn=978-1-4013-9551-3|page=PT42|access-date=September 25, 2016|archive-url=https://web.archive.org/web/20160505192859/https://books.google.com/books?id=mVqZAAAAQBAJ&pg=PT42|archive-date=May 5, 2016|url-status=live}}</ref>

=== Removal of false information ===
Fernanda Viégas of the MIT Media Lab and Martin Wattenberg and Kushal Dave of IBM Research studied the flow of editing in the Wikipedia model, with emphasis on breaks in flow (from vandalism or substantial rewrites), showing the dynamic flow of material over time.<ref name=chi2004>{{cite web| title=Studying Cooperation and Conflict between Authors with history flow Visualizations| first1=Fernanda B.| last1=Viégas| first2=Martin| last2=Wattenberg| first3=Kushal| last3=Dave| publisher=CHI 2004, Vol. 6 No. 1| date=April 29, 2004| url=http://alumni.media.mit.edu/~fviegas/papers/history_flow.pdf| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20060125025047/http://alumni.media.mit.edu/~fviegas/papers/history_flow.pdf| archive-date=January 25, 2006| url-status=live}}</ref> From a sample of vandalism edits on the English Wikipedia during May 2003, they found that most such acts were repaired within minutes, summarizing:
{{blockquote|We've examined many pages on Wikipedia that treat controversial topics, and have discovered that most have, in fact, been vandalized at some point in their history. But we've also found that vandalism is usually repaired extremely quickly—so quickly that most users will never see its effects.<ref name="History flow: results">{{cite web|title=History flow: results |first1=Fernanda B. |last1=Viégas |first2=Martin |last2=Wattenberg |first3=Kushal |last3=Dave |publisher=IBM Collaborative User Experience Research Group |year=2003 |website=research.ibm.com |url=http://www.research.ibm.com/visual/projects/history_flow/results.htm |access-date=July 7, 2016 |url-status=dead |archive-url=https://web.archive.org/web/20061102094447/http://www.research.ibm.com/visual/projects/history_flow/results.htm |archive-date=November 2, 2006 }}</ref>}}
They also stated that "it is essentially impossible to find a crisp definition of vandalism".<ref name=chi2004/>

Lih (2004) compared articles before and after they were mentioned in the press, and found that externally referenced articles are of higher quality work. An informal assessment by the popular IT magazine ''PC Pro'' for its 2007 article "Wikipedia Uncovered"<ref name="uncovered" /> tested Wikipedia by introducing 10 errors that "varied between bleeding obvious and deftly subtle" into articles (the researchers later corrected the articles they had edited). Labeling the results "impressive" it noted that all but one was noted and fixed within the hour, and that "the Wikipedians' tools and know-how were just too much for our team." A second series of another 10 tests, using "far more subtle errors" and additional techniques to conceal their nature, met similar results: "despite our stealth attempts the vast majority... were discovered remarkably quickly... the ridiculously minor Jesse James error was corrected within a minute and a very slight change to Queen Anne's entry was put right within two minutes". Two of the latter series were not detected. The article concluded that "Wikipedia corrects the vast majority of errors within minutes, but if they're not spotted within the first day the chances... dwindle as you're then relying on someone to spot the errors while reading the article rather than reviewing the edits".

A study in late 2007 systematically inserted inaccuracies into Wikipedia entries about the lives of philosophers. Depending on how exactly the data are interpreted, either one third or one half of the inaccuracies were corrected within 48 hours.<ref>Magnus, P.D. [http://www.uic.edu/htbin/cgiwrap/bin/ojs/index.php/fm/article/viewArticle/2115/2027 Early response to false claims in Wikipedia] {{Webarchive|url=https://web.archive.org/web/20101203080013/http://www.uic.edu/htbin/cgiwrap/bin/ojs/index.php/fm/article/viewArticle/2115/2027 |date=December 3, 2010 }}. [http://www.uic.edu/htbin/cgiwrap/bin/ojs/index.php/fm/index First Monday] {{Webarchive|url=https://web.archive.org/web/20090731112057/http://www.uic.edu/htbin/cgiwrap/bin/ojs/index.php/fm/index |date=July 31, 2009 }}, 13 (9): September 1, 2008</ref>

A 2007 peer-reviewed study<ref name="mngrp07">Reid Priedhorsky, Jilin Chen, Shyong (Tony) K. Lam, Katherine Panciera, [[Loren Terveen]], [[John T. Riedl|John Riedl]], "Creating, destroying, and restoring value in wikipedia", Proc. GROUP 2007, doi: [http://doi.acm.org/10.1145/1316624.1316663 ACM.org]</ref> that measured the actual number of page views with damaged content stated: "42% of damage is repaired almost immediately, i.e., before it can confuse, offend, or mislead anyone. Nonetheless, there are still hundreds of millions of damaged views."<ref name="mngrp07"/>

[[Loc Vu-Quoc]], professor for Mechanical and Aerospace Engineering at the [[University of Florida]], stated in 2008 that "sometimes errors may go for years without being corrected as experts don't usually read Wikipedia articles in their own field to correct these errors".<ref>Vu-Quoc, L. [http://clesm.mae.ufl.edu/wiki.pub/index.php/Configuration_integral_%28statistical_mechanics%29 Configuration integral] {{webarchive |url=https://web.archive.org/web/20120428193950/http://clesm.mae.ufl.edu/wiki.pub/index.php/Configuration_integral_%28statistical_mechanics%29 |date=April 28, 2012 }}, VQWiki, 2008.</ref>

=== Susceptibility to bias ===
==== Individual bias and the WikiScanner tool ====
{{main|WikiScanner}}
In August 2007, WikiScanner, a tool developed by [[Virgil Griffith]] of the California Institute of Technology, was released to match anonymous IP edits in the encyclopedia with an extensive database of addresses. News stories appeared about IP addresses from various organizations such as the [[Central Intelligence Agency]], the [[Democratic Congressional Campaign Committee]], [[Diebold|Diebold, Inc.]] and the [[Government of Australia|Australian government]] being used to make edits to Wikipedia articles, sometimes of an opinionated or questionable nature.<ref>{{cite news |last=Blakely |first=Rhys |title=Exposed: guess who has been polishing their Wikipedia entries? |url=http://business.timesonline.co.uk/tol/business/industry_sectors/media/article2264150.ece |work=The Times of London |archive-url=https://web.archive.org/web/20110612023406/http://business.timesonline.co.uk/tol/business/industry_sectors/media/article2264150.ece |archive-date=June 12, 2011 |date=August 15, 2007 |url-status=dead}}</ref> The [[BBC]] quoted a Wikimedia spokesperson as praising the tool: "We really value transparency and the scanner really takes this to another level. Wikipedia Scanner may prevent an organization or individuals from editing articles that they're really not supposed to."<ref>{{cite news|url=http://news.bbc.co.uk/1/hi/technology/6947532.stm|title=Wikipedia 'shows CIA page edits'|date=August 15, 2007|access-date=March 14, 2021|work=BBC News|first=Jonathan|last=Fildes|archive-url=https://web.archive.org/web/20090111230821/http://news.bbc.co.uk/1/hi/technology/6947532.stm|archive-date=January 11, 2009|url-status=live}}</ref>

The WikiScanner story was also covered by ''[[The Independent]]'', which stated that many "censorial interventions" by editors with vested interests on a variety of articles in Wikipedia had been discovered:
{{blockquote|[Wikipedia] was hailed as a breakthrough in the democratisation of knowledge. But the online encyclopedia has since been hijacked by forces who decided that certain things were best left unknown... Now a website designed to monitor editorial changes made on Wikipedia has found thousands of self-serving edits and traced them to their original source. It has turned out to be hugely embarrassing for armies of political spin doctors and corporate revisionists who believed their censorial interventions had gone unnoticed.<ref>{{cite news|url=http://news.independent.co.uk/sci_tech/article2874112.ece|title=Wikipedia and the art of censorship|first=Robert|last=Verkaik|date=2007-08-18|newspaper=The Independent|access-date=2007-10-27|location=London|archive-url=https://web.archive.org/web/20090109005336/http://news.independent.co.uk/sci_tech/article2874112.ece|archive-date=2009-01-09|url-status=dead}}</ref>}} Not everyone hailed WikiScanner as a success for Wikipedia. [[Oliver Kamm]], in a column for ''[[The Times]]'', argued instead that:

<blockquote>The WikiScanner is thus an important development in bringing down a pernicious influence on our intellectual life. Critics of the web decry the medium as the cult of the amateur. Wikipedia is worse than that; it is the province of the covert lobby. The most constructive course is to stand on the sidelines and jeer at its pretensions.<ref name=okw>{{cite news|url=https://www.thetimes.com/uk/politics/article/wisdom-more-like-dumbness-of-the-crowds-2br5d8ndv9k|title=Wisdom? More like dumbness of the crowds|first=Oliver|last=Kamm|work=[[The Times]]|location=London|date=August 16, 2007|access-date=March 14, 2021|url-access=limited|archive-url=https://web.archive.org/web/20090509094518/http://www.timesonline.co.uk/tol/comment/columnists/guest_contributors/article2267665.ece|archive-date=May 9, 2009|url-status=live}}</ref></blockquote>

WikiScanner only reveals [[conflict of interest]] when the editor does not have a Wikipedia account and their IP address is used instead. Conflict of interest editing done by editors with accounts is not detected, since those edits are anonymous to everyone—except for "a handful of privileged Wikipedia admins".<ref>{{cite web |url=https://www.theregister.co.uk/2007/12/18/the_wikipedia_paradox/ |first=Cade |last=Metz |title=Truth, anonymity and the Wikipedia Way: Why it's broke and how it can be fixed |website=The Register |date=December 18, 2007 |access-date=March 14, 2021 |archive-url=https://web.archive.org/web/20170810142341/https://www.theregister.co.uk/2007/12/18/the_wikipedia_paradox/ |archive-date=August 10, 2017 |url-status=live  }}</ref>

==== Coverage ====
{{see also|Criticism of Wikipedia#Systemic bias in coverage|Academic studies about Wikipedia#A minority of editors produce the majority of persistent content}}
Wikipedia has been accused of [[systemic bias]], which is to say its general nature leads, without necessarily any conscious intention, to the propagation of various prejudices. Although many articles in newspapers have concentrated on minor, indeed trivial, factual errors in Wikipedia articles, there are also concerns about large-scale, presumably unintentional effects from the increasing influence and use of Wikipedia as a research tool at all levels. In an article in the ''[[Times Higher Education]]'' magazine (London) [[philosopher]] Martin Cohen frames Wikipedia of having "become a monopoly" with "all the prejudices and ignorance of its creators", which he describes as a "youthful cab-drivers" perspective.<ref name="Cohen 26">{{Cite journal |title=Encyclopaedia Idiotica |first=Martin |last=Cohen |journal=Times Higher Education |issue=August 28, 2008 |page=26 |url=http://www.timeshighereducation.co.uk/story.asp?storycode=403327 |date=August 27, 2008 |access-date=May 31, 2011 |archive-url=https://web.archive.org/web/20110906163412/http://www.timeshighereducation.co.uk/story.asp?storycode=403327 |archive-date=September 6, 2011 |url-status=live  }}</ref> Cohen's argument, however, finds a grave conclusion in these circumstances: "To control the reference sources that people use is to control the way people comprehend the world. Wikipedia may have a benign, even trivial face, but underneath may lie a more sinister and subtle threat to freedom of thought."<ref name="Cohen 26"/> That freedom is undermined by what he sees as what matters on Wikipedia, "not your sources but the 'support of the community'."<ref name="Cohen 26"/>

Critics also point to the tendency to cover topics in a detail disproportionate to their importance. For example, [[Stephen Colbert]] once mockingly praised Wikipedia for having a "longer entry on '[[lightsaber]]s' than it does on the '[[printing press]]'."<ref name="ColbertReport">Stephen Colbert, ''The Colbert Report'', episode 3109, August 21, 2007.</ref> In an interview with ''The Guardian'', Dale Hoiberg, the editor-in-chief of ''[[Encyclopædia Britannica]]'', noted:<blockquote>People write of things they're interested in, and so many subjects don't get covered; and news events get covered in great detail. In the past, the entry on [[Hurricane Frances]] was more than five times the length of that on [[Chinese art]], and the entry on ''[[Coronation Street]]'' was twice as long as the article on [[Tony Blair]].<ref name="Who"/></blockquote>

This critical approach has been satirised as "Wikigroaning", a term coined by Jon Hendren<ref name="wsj">{{Cite journal |title=Oh, that John Locke |first=Jamin |last=Brophy-Warren |journal=The Wall Street Journal |date=June 17, 2007 |issue=June 16, 2007 |pages=P3 |url=https://www.wsj.com/articles/SB118194482542637175 |access-date=August 8, 2017 |archive-url=https://web.archive.org/web/20170904182902/https://www.wsj.com/articles/SB118194482542637175 |archive-date=September 4, 2017 |url-status=live  }}</ref> of the website [[Something Awful]].<ref>{{cite web |title=The Art of Wikigroaning |date=June 5, 2007 |first=Johnny "DocEvil" |last=Hendren |access-date=June 17, 2007 |work=Something Awful |url=http://www.somethingawful.com/d/news/wikigroaning.php |archive-url=https://web.archive.org/web/20070616004859/http://www.somethingawful.com/d/news/wikigroaning.php |archive-date=June 16, 2007 |url-status=live }}</ref> In the game, two articles (preferably with similar names) are compared: one about an acknowledged serious or classical subject and the other about a popular topic or current event.<ref name="Abrown">{{Cite journal | first=Andrew | last=Brown | issue=June 14, 2007 | title=No amount of collaboration will make the sun orbit the Earth | journal=The Guardian | url=http://technology.guardian.co.uk/weekly/story/0,,2101810,00.html | location=London | date=June 14, 2007 | access-date=March 27, 2010 | archive-url=https://web.archive.org/web/20070623205917/http://technology.guardian.co.uk/weekly/story/0,,2101810,00.html | archive-date=June 23, 2007 | url-status=live | df=mdy-all }}</ref> Defenders of a broad inclusion criteria have held that the encyclopedia's coverage of pop culture does not impose space constraints on the coverage of more serious subjects (see "[[:meta:Wiki is not paper|Wiki is not paper]]"). Ivor Tossell wrote:

<blockquote>That Wikipedia is chock full of useless arcana (and did you know, by the way, that the article on "Debate" is shorter than the piece that weighs the relative merits of the 1978 and 2003 versions of Battlestar Galactica?) isn't a knock against it: Since it can grow infinitely, the silly articles aren't depriving the serious ones of space.<ref>{{cite news|url=https://www.theglobeandmail.com/technology/duality-of-wikipedia/article1087547/|title=Duality of Wikipedia|first=Ivor|last=Tossell|work=[[The Globe and Mail]]|date=June 15, 2007|access-date=October 4, 2012|archive-url=https://web.archive.org/web/20121221014630/http://www.theglobeandmail.com/technology/duality-of-wikipedia/article1087547/|archive-date=December 21, 2012|url-status=live}}</ref></blockquote>

Wikipedia has been accused of deficiencies in comprehensiveness because of its voluntary nature, and of reflecting the systemic biases of its contributors. Wikipedia co-founder [[Larry Sanger]] stated in 2004, "when it comes to relatively specialized topics (outside of the interests of most of the contributors), the project's credibility is very uneven."<ref name="SangerElitism">{{cite web| title=Why Wikipedia Must Jettison Its Anti-Elitism| first=Larry| last=Sanger| work=[[Kuro5hin]]| date=December 31, 2004| url=http://www.kuro5hin.org/story/2004/12/30/142458/25| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20060104040708/http://www.kuro5hin.org/story/2004/12/30/142458/25| archive-date=January 4, 2006| url-status=live| df=mdy-all| author-link=Larry Sanger}}</ref> He expanded on this 16 years later in May 2020, by comparing how coverage impacts tone between the articles of U.S. presidents [[Donald Trump]] (seen as negative) and [[Barack Obama]] (seen as positive).<ref>{{cite web |last=Sanger |first=Larry |date=2020-05-14 |title=Wikipedia Is Badly Biased |url=https://larrysanger.org/2020/05/wikipedia-is-badly-biased/ |access-date=2025-03-08 |website=larrysanger.org}}</ref><ref>{{cite web |last=Baker |first=Gerard |date=2020-05-27 |title=Big tech is blatantly biased against Trump |url=https://www.thetimes.com/article/big-tech-is-blatantly-biased-against-trump-qmdd2s6l7 |access-date=2025-03-08 |website=The Times and The Sunday Times}}</ref>

In a [[GamesRadar]] editorial, columnist Charlie Barrat juxtaposed Wikipedia's coverage of [[video game]]-related topics with its smaller content about topics that have greater real-world significance, such as God, World War II and former U.S. presidents.<ref>{{cite web | url=http://www.gamesradar.com/pc/f/the-wtf-world-of-wikipedia/a-2008062510326553058 | title=The WTF World of Wikipedia | access-date=February 20, 2009 | first=Charlie | last=Barratt | date=June 25, 2008 | publisher=[[Future Publishing]] | pages=1–5 | archive-url=https://web.archive.org/web/20080721014159/http://www.gamesradar.com/pc/f/the-wtf-world-of-wikipedia/a-2008062510326553058 | archive-date=July 21, 2008 | url-status=live | df=mdy-all }}</ref> Wikipedia has been praised for making it possible for articles to be updated or created in response to current events. Its editors have also argued that, as a website, Wikipedia is able to include articles on a greater number of subjects than print encyclopedias can.<ref>"[[Wikipedia:Replies to common objections]]", Wikipedia, 22:53 April 13, 2005.</ref>

A 2011 study reported evidence of cultural bias in Wikipedia articles about famous people on both the English and Polish Wikipedias. These biases included those pertaining to the cultures of both the United States and Poland on each of the corresponding-language Wikipedias, as well as a pro-U.S./English-language bias on both of them.<ref>{{cite journal|last1=Callahan|first1=Ewa S.|last2=Herring|first2=Susan C.|title=Cultural bias in Wikipedia content on famous persons|journal=Journal of the American Society for Information Science and Technology|date=October 2011|volume=62|issue=10|pages=1899–1915|doi=10.1002/asi.21577|s2cid=14767483 }}</ref>

===== Notability of article topics =====
{{transcluded section|Criticism of Wikipedia}}
{{trim|{{#section-h:Criticism of Wikipedia|Notability of article topics}}}}

===== Political bias =====
{{main|Ideological bias on Wikipedia}}
Wikipedia co-founder [[Jimmy Wales]] stated in 2006: "The Wikipedia community is very diverse, from [[Modern liberalism in the United States|liberal]] to [[Conservatism in the United States|conservative]] to [[Libertarianism in the United States|libertarian]] and beyond. If averages mattered, and due to the nature of the wiki software (no voting) they almost certainly don't, I would say that the Wikipedia community is slightly more liberal than the U.S. population on average, because we are global and the international community of English speakers is slightly more liberal than the U.S. population. There are no data or surveys to back that."<ref>{{cite web|url=https://www.pbs.org/mediashift/2006/04/email_debatewales_discusses_po.html|title=Wales Discusses Political Bias on Wikipedia|first=Mark|last=Glaser|publisher=PBS Mediashift|date=April 21, 2006|access-date=August 21, 2007|archive-url=https://web.archive.org/web/20070819200008/http://www.pbs.org/mediashift/2006/04/email_debatewales_discusses_po.html|archive-date=August 19, 2007|url-status=dead}}</ref>

A number of politically conservative commentators have argued that [[Criticism of Wikipedia#Partisanship|Wikipedia's coverage is affected by liberal bias]].<ref name="Slate-Neutrality">{{cite news | url=https://slate.com/technology/2020/06/wikipedia-george-floyd-neutrality.html | last=Harrison | first=Stephen | title=How Wikipedia Became a Battleground for Racial Justice | work=[[Slate (magazine)|Slate]] | date=June 9, 2020 | access-date=August 17, 2021 | archive-date=November 3, 2021 | archive-url=https://web.archive.org/web/20211103084021/https://slate.com/technology/2020/06/wikipedia-george-floyd-neutrality.html | url-status=live }}</ref> [[Andrew Schlafly]] created [[Conservapedia]] because he found Wikipedia "increasingly anti-Christian and anti-American" for its frequent use of [[American and British English spelling differences|British spelling]] and coverage of topics like [[creationism]] and the effect of Christianity on [[the Renaissance]].<ref name="Guardian">{{Cite news | last = Johnson | first = Bobbie | url = https://www.theguardian.com/international/story/0,,2024434,00.html | title = Conservapedia—the US religious right's answer to Wikipedia | work = The Guardian | date = March 1, 2007 | location = London | access-date = March 27, 2010 | archive-date = February 17, 2022 | archive-url = https://web.archive.org/web/20220217233021/https://www.theguardian.com/technology/2007/mar/01/wikipedia.news | url-status = live }}</ref> In 2007, an article in ''[[The Christian Post]]'' criticised Wikipedia's coverage of [[intelligent design]], saying that it was biased and hypocritical.<ref>{{cite web |url=https://www.christianpost.com/news/design-proponents-accuse-wikipedia-of-bias-hypocrisy-27307/ |title='Design' Proponents Accuse Wikipedia of Bias, Hypocrisy |last=Huntington |first=Doug |date=May 9, 2007 |access-date=June 1, 2018 |work=The Christian Post |archive-url=https://web.archive.org/web/20110514104736/https://www.christianpost.com/news/design-proponents-accuse-wikipedia-of-bias-hypocrisy-27307/ |archive-date=May 14, 2011 |url-status=dead}}</ref> [[Lawrence Solomon]] of the ''[[National Review]]'' stated that Wikipedia articles on subjects like [[global warming]], intelligent design, and ''[[Roe v. Wade]]'' are slanted in favor of liberal views.<ref>{{Cite news|last=Solomon|first=Lawrence|title=Wikipropaganda On Global Warming|url=https://www.cbsnews.com/news/wikipropaganda-on-global-warming/|work=National Review|publisher=CBS News|date=July 8, 2008|access-date=July 20, 2008|archive-url=https://web.archive.org/web/20080828202634/http://www.cbsnews.com/stories/2008/07/08/opinion/main4241293.shtml|archive-date=August 28, 2008|url-status=live}}</ref>{{primary source inline|date=August 2021}} In a September 2010 issue of the conservative weekly ''[[Human Events]]'', [[Rowan Scarborough]] presented a critique of Wikipedia's coverage of American politicians prominent in the approaching [[United States midterm election|midterm elections]] as evidence of systemic liberal bias. Scarborough compared the biographical articles of liberal and conservative opponents in Senate races in the Alaska Republican primary and the Delaware and Nevada general election, emphasizing the quantity of negative coverage of [[Tea Party movement]]-endorsed candidates. He also cites some criticism by Lawrence Solomon and quotes in full the lead section of Wikipedia's article on the conservative wiki [[Conservapedia]] as evidence of an underlying bias.<ref name="scarborough">{{cite web|last=Scarborough|first=Rowan|author-link=Rowan Scarborough|url=http://www.humanevents.com/article.php?id=39139|title=Wikipedia Whacks the Right|date=September 27, 2010|access-date=October 3, 2010|work=[[Human Events]]|archive-url=https://web.archive.org/web/20101207081401/http://www.humanevents.com/article.php?id=39139|archive-date=December 7, 2010|url-status=dead}}</ref>{{primary source inline|date=August 2021}} Jonathan Sidener of ''[[The San Diego Union-Tribune]]'' wrote that "vandalism and self-serving misinformation [are] common particularly in the political articles".<ref>{{cite web | url=http://legacy.sandiegouniontribune.com/uniontrib/20060923/news_lz1n23wiki.html | title=Wikipedia co-founder looks to add accountability, end anarchy | work=[[The San Diego Union-Tribune]] | date=September 23, 2006 | access-date=January 16, 2017 | author=Sidener, Jonathan | archive-url=https://web.archive.org/web/20180117190455/http://legacy.sandiegouniontribune.com/uniontrib/20060923/news_lz1n23wiki.html | archive-date=January 17, 2018 | url-status=live | df=mdy-all }}</ref>{{primary source inline|date=August 2021}} A 2015 study found that negative facts are more likely to be removed from Wikipedia articles on U.S. senators than positive facts but did not find any significant difference relating to political affiliation.<ref>{{cite journal|title = Editorial Bias in Crowd-Sourced Political Information|journal = PLOS ONE|date = September 2, 2015|pmc = 4558055|pmid = 26331611|pages = e0136327|volume = 10|issue = 9|doi = 10.1371/journal.pone.0136327|first1 = Joshua L.|last1 = Kalla|first2 = Peter M.|last2 = Aronow|bibcode = 2015PLoSO..1036327K|doi-access = free}}</ref>

Amid the [[George Floyd protests]], there were several disputes over [[racial justice]] on Wikipedia.<ref name="Slate-Neutrality"/> The [[Wikipedia community]] voted against a proposal to black out the website in support of [[Black Lives Matter]] because it may have threatened Wikipedia's reputation for [[Wikipedia:Neutral point of view|neutrality]].<ref name="Slate-Neutrality" />{{refn|There was also a dispute on the "[[George Floyd]]", "[[George Floyd protests]]", and "[[Murder of George Floyd]]" articles on whether they should mention Floyd's prior criminal charges, use of the word ''riot'' (rejected because most [[Wikipedia:Reliable sources|reliable sources]] did not refer to them as [[riot]]s), and change it from ''Death'' to ''Killing'', respectively. While ''death'' was the more neutral term, editors felt that ''killing'' was the more accurate term and ''neutral'' by definition. As for the criminal charges, those in favour cited in support that [[WP:NOTCENSORED|Wikipedia is not censored]], while those opposed cited [[Wikipedia:Weight|weight policy]], positing that it would be undue to add because his past criminal history did not have relevance to his murder.<ref name="Slate-Neutrality"/>|group=nb}} It also led to the creation of the [[Wikipedia:WikiProject Black Lives Matter|WikiProject Black Lives Matter]], in line with [[AfroCROWD]]'s [[Juneteenth]] efforts to improve the coverage of [[civil rights movement]]-related topics; the Black Lives Matter project was nominated for deletion on the grounds that it was "non-neutral advocacy".<ref name="Slate-Neutrality"/> In Wikipedia, neutrality is more of a process that is achieved through [[Wikipedia:Consensus|consensus]]. Social scientist Jackie Koerner took issue with the word ''neutrality'' and said she preferred the word ''balance'' to neutrality because she believed that one of Wikipedia's goals should be [[knowledge equity]].<ref name="Slate-Neutrality"/>

The [[Japanese Wikipedia]] has been accused of [[Japanese history textbook controversies|right-wing historical revisionism]], particularly on articles related to its role in World War II and colonialism, by a number of scholars.<ref name=":1">{{Cite book |last=Schneider |first=Florian |url=https://books.google.com/books?id=DXBoDwAAQBAJ |title=China's Digital Nationalism |date=August 16, 2018 |publisher=Oxford University Press |isbn=978-0-19-087681-4 |pages=123–124 |language=en}}</ref><ref name=":2">{{Cite journal |last=Gustafsson |first=Karl |date=July 18, 2019 |title=International reconciliation on the Internet? Ontological security, attribution and the construction of war memory narratives in Wikipedia |journal=International Relations |language=en |volume=34 |issue=1 |pages=3–24 |doi=10.1177/0047117819864410 |issn=0047-1178 |s2cid=200020669 |doi-access=free}}</ref><ref name="YumikoSatoSlate">{{Cite web |last=Sato |first=Yumiko |date=March 19, 2021 |title=Non-English Editions of Wikipedia Have a Misinformation Problem |url=https://slate.com/technology/2021/03/japanese-wikipedia-misinformation-non-english-editions.html |access-date=August 23, 2021 |website=[[Slate (magazine)|Slate]] |publisher=The Slate Group}}</ref><ref name="YumikoSatoJournal">{{Cite web |last=Sato |first=Yumiko |date=January 9, 2021 |script-title=ja:日本語版ウィキペディアで「歴史修正主義」が広がる理由と解決策 |trans-title=Reasons Why "Historical Revisionism" is Widespread on Japanese Wikipedia and Solutions for It |url=https://yumikosato.com/2021/01/09/japanese-wikipedia/ |access-date=August 23, 2021 |website=Yumiko Sato's Music Therapy Journal |language=Japanese}}</ref> The issue has been the subject of research supported by the Wikimedia Foundation.<ref>{{Cite journal |last1=Kim |first1=Taehee |last2=Garcia |first2=David |last3=Aragón |first3=Pablo |date=May 11, 2023 |title=Controversies over Historical Revisionism in Wikipedia |url=https://wikiworkshop.org/2023/papers/WikiWorkshop2023_paper_22.pdf |journal=Wiki Workshop 2023 |publisher=[[Wikimedia Foundation]]}}</ref>

=== Reliability as a source in other contexts ===
Despite its status as a non-primary source, Wikipedia has been cited as evidence in some legal cases. In January 2007, ''The New York Times'' reported that U.S. courts vary greatly in their treatment of Wikipedia as a source of information, with over 100 judicial rulings having relied on the encyclopedia, including those involving taxes, narcotics, and civil issues such as personal injury and matrimonial issues.<ref name=NYT1.29.07>Cohen, Noam (January 29, 2007). [https://www.nytimes.com/2007/01/29/technology/29wikipedia.html "Courts Turn to Wikipedia, but Selectively"] {{Webarchive|url=https://web.archive.org/web/20170318070416/http://www.nytimes.com/2007/01/29/technology/29wikipedia.html |date=March 18, 2017 }}. ''The New York Times''.</ref>

In April 2012, ''The Wall Street Journal'' reported that in the five years since the 2007 ''The New York Times'' story, federal courts of appeals had cited Wikipedia about 95 times. The story also reported that the U.S. Court of Appeals for the Fourth Circuit vacated convictions in a cockfighting case because a juror used Wikipedia to research an element of the crime, expressing in its decision concerns about Wikipedia's reliability.<ref>Palazzolo, Joe (April 23, 2012). [https://blogs.wsj.com/law/2012/04/23/which-federal-appeals-court-cites-wikipedia-most/?KEYWORDS=wikipedia "Which Federal Appeals Court Cites Wikipedia Most Often?"] {{Webarchive|url=https://web.archive.org/web/20181120091419/https://blogs.wsj.com/law/2012/04/23/which-federal-appeals-court-cites-wikipedia-most/?KEYWORDS=wikipedia |date=November 20, 2018 }}. ''[[The Wall Street Journal]]''.</ref>

In one notable case, the trademark of [[Formula One]] racing decision,<ref>{{cite web| title=Case ref. O-169-07: In the matter of application no 2277746C by Formula One Licensing B.V., to register the trade mark: "F1"| publisher=UK Government Intellectual Property Office| date=June 14, 2007| url=http://www.ipo.gov.uk/tm/t-decisionmaking/t-challenge/t-challenge-decision-results/o16907.pdf| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20071031053106/http://www.ipo.gov.uk/tm/t-decisionmaking/t-challenge/t-challenge-decision-results/o16907.pdf| archive-date=October 31, 2007| url-status=live}}</ref> the [[UK Intellectual Property Office]] considered both the reliability of Wikipedia, and its usefulness as a reliable source of evidence:
{{blockquote|Wikipedia has sometimes suffered from the self-editing that is intrinsic to it, giving rise at times to potentially [[libel]]lous statements. However, inherently, I cannot see that what is in Wikipedia is any less likely to be true than what is published in a book or on the websites of news organizations. [Formula One's lawyer] did not express any concerns about the Wikipedia evidence [presented by the plaintiff]. I consider that the evidence from Wikipedia can be taken at face value." The case turned substantively upon evidence cited from Wikipedia in 2006 as to the usage and interpretation of the term ''[[Formula One]]''.}}

In the United States, the [[United States Court of Federal Claims]] has ruled that "Wikipedia may not be a reliable source of information."<ref>Nordwall v. Secretary of Health & Human Services, No. 05-123V, 2008 WL 857661, at *7 n.6 (Fed. Cl. February 19, 2008) as cited in [http://docs.justia.com/cases/federal/district-courts/california/candce/5:2008cv00904/204116/62/ Capcom Co., Ltd, et al. v. The MKR Group, Inc., No. C 08-0904 RS] {{Webarchive|url=https://web.archive.org/web/20120927221002/http://docs.justia.com/cases/federal/district-courts/california/candce/5:2008cv00904/204116/62/ |date=September 27, 2012 }}</ref> and "...Articles [from Wikipedia] do not—at least on their face—remotely meet this reliability requirement...A review of the Wikipedia website reveals a pervasive and, for our purposes, disturbing [[Wikipedia:General disclaimer|series of disclaimers]]...".<ref name=NYT1.29.07/><ref>Campbell v. Sec'y of Health & Human Servs., 69 Fed. Cl. 775, 781 (Ct. Cl. 2006)</ref> Such disclaimers include the Wikipedia not being able to guarantee the validity of the information on its articles and having no formal peer review.

Among other reasons for these statements about Wikipedia's reliability are the stability of the articles (which due to editing may cause new readers to find information that differs from the originally cited) and, according to Stephen Gillers, a professor at New York University Law School, "the most critical fact is public acceptance", therefore "a judge should not use Wikipedia when the public is not prepared to accept it as authority".<ref>{{Cite news|title = Courts Turn to Wikipedia, but Selectively|url = https://www.nytimes.com/2007/01/29/technology/29wikipedia.html|newspaper = The New York Times|date = January 29, 2007|access-date = December 8, 2015|issn = 0362-4331|first = Noam|last = Cohen |author-link = Noam Cohen|archive-url = https://web.archive.org/web/20150922174408/http://www.nytimes.com/2007/01/29/technology/29wikipedia.html|archive-date = September 22, 2015|url-status = live}}</ref>

Wikipedia has also become a key source for some current news events such as the 2007 [[Virginia Tech massacre]], when ''[[The New York Times]]'' cites Wikimedia to report 750,000 page views of the article in the two days after the event:

{{blockquote|Even ''[[The Roanoke Times]]'', which is published near [[Blacksburg, Virginia]], where the university is located, noted on Thursday that Wikipedia "has emerged as the clearinghouse for detailed information on the event".<ref name="vtech">{{cite web| title=Wikipedia emerges as key source for Virginia Tech shootings| publisher=Cyberjournalist.net| date=24 April 2007| url=http://www.cyberjournalist.net/news/004178.php| access-date=2007-10-31| archive-url=https://web.archive.org/web/20071022200632/http://cyberjournalist.net/news/004178.php| archive-date=22 October 2007| url-status=dead}}—''cyberjournalist.net'' cites this article {{cite news| title=The Latest on Virginia Tech, From Wikipedia| first=Noam| last=Cohen | author-link=Noam Cohen| work=[[The New York Times]]| date=April 23, 2007| url=https://www.nytimes.com/2007/04/23/technology/23link.html?_r=2&oref=slogin&oref=slogin| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20090415231958/http://www.nytimes.com/2007/04/23/technology/23link.html?_r=2&oref=slogin&oref=slogin| archive-date=April 15, 2009| url-status=live}} for the above quote.</ref>}}

''[[The Washington Post]]'' commented, in the context of [[2008 United States presidential election|2008 presidential election]] candidate biographies, that despite occasional brief vandalism, "it's hard to find a more up-to-date, detailed, thorough article on [[Barack Obama|Obama]] than Wikipedia's. As of Friday (14 September 2007), Obama's article—more than 22 pages long, with 15 sections covering his personal and professional life—had a reference list of 167 sources."<ref>{{cite news| title=On Wikipedia, Debating 2008 Hopefuls' Every Facet| first=Jose Antonio |last=Vargas| newspaper=[[The Washington Post]], Page A01| date=September 17, 2007| url=https://www.washingtonpost.com/wp-dyn/content/article/2007/09/16/AR2007091601699.html?hpid=topnews| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20121103053949/http://www.washingtonpost.com/wp-dyn/content/article/2007/09/16/AR2007091601699.html?hpid=topnews| archive-date=November 3, 2012| url-status=live| df=mdy-all}}</ref>

=== Broad opinions ===
Several commentators have drawn a middle ground, asserting that the project contains much valuable knowledge and has some reliability, even if the degree is not yet assessed with certainty. Others taking this view include [[danah boyd]], [sic] who in 2005 discussed Wikipedia as an academic source, concluding that "[i]t will never be an encyclopedia, but it will contain extensive knowledge that is quite valuable for different purposes",<ref>{{cite web| title=Academia and Wikipedia| first=danah| last=boyd| publisher=Many-to-Many| date=January 4, 2005| url=http://www.corante.com/many/archives/2005/01/04/academia_and_wikipedia.php| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20060112003204/http://www.corante.com/many/archives/2005/01/04/academia_and_wikipedia.php| archive-date=January 12, 2006| url-status=dead| df=mdy-all| author-link=danah boyd}}</ref> and [[Bill Thompson (technology writer)|Bill Thompson]] who stated "I use the Wikipedia a lot. It is a good starting point for serious research, but I would never accept something that I read there without checking."<ref name="Thompson" />

''[[Information Today, Inc.|Information Today]]'''s March 2006 article<ref name="informationtoday"/> concludes on a similar theme:
{{blockquote|The inconvenient reality is that people and their products are messy, whether produced in a top-down or bottom-up manner. Almost every source includes errors... Many non-fiction books are produced via an appallingly sloppy process... In this author's opinion, the flap over Wikipedia was significantly overblown, but contained a silver lining: People are becoming more aware of the perils of accepting information at face value. They have learned not to consult just one source.}}

[[Dan Gillmor]], a [[Silicon Valley]] commentator and author commented in October 2004 that, "I don't think anyone is saying Wikipedia is an absolute replacement for a traditional encyclopedia. But in the topics I know something about, I've found Wikipedia to be as accurate as any other source I've found."<ref name="Who" />

[[Larry Sanger]] stated on [[Kuro5hin]] in 2001 that "Given enough eyeballs, all errors are shallow",<ref>{{cite web| title=Wikipedia is wide open. Why is it growing so fast? Why isn't it full of nonsense?| first=Larry| last=Sanger| work=[[Kuro5hin]]| date=September 24, 2001| url=http://www.kuro5hin.org/story/2001/9/24/43858/2479| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20071010041752/http://www.kuro5hin.org/story/2001/9/24/43858/2479| archive-date=October 10, 2007| url-status=live| df=mdy-all| author-link=Larry Sanger}}</ref> which is a paraphrase of [[Linus' Law]] of open-source development.

Likewise, technology figure [[Joi Ito]] wrote on Wikipedia's authority, "[a]lthough it depends a bit on the field, the question is whether something is more likely to be true coming from a source whose resume sounds authoritative, or a source that has been viewed by hundreds of thousands of people (with the ability to comment) and has survived."<ref>{{cite web| title=Wikipedia attacked by ignorant reporter| first=Joi| last=Ito| publisher=Joi Ito's Web| date=August 29, 2004| url=http://joi.ito.com/archives/2004/08/29/wikipedia_attacked_by_ignorant_reporter.html#c014592| access-date=October 31, 2007| archive-url=https://web.archive.org/web/20070928040536/http://joi.ito.com/archives/2004/08/29/wikipedia_attacked_by_ignorant_reporter.html#c014592| archive-date=September 28, 2007| url-status=live| df=mdy-all| author-link=Joi Ito}}</ref>

In a 2008 letter to the editor of ''[[Physics Today]]'', Gregg Jaeger, an associate professor at [[Boston University]],<ref>Jaeger, G.[http://people.bu.edu/jaeger professional webpage] {{webarchive |url=https://web.archive.org/web/20030517163206/http://people.bu.edu/jaeger |date=May 17, 2003 }}</ref> has characterized Wikipedia as a medium that is susceptible to fostering "anarchy and distortions" in relation to scientific information.<ref>{{Cite magazine|url=https://physicstoday.scitation.org/doi/10.1063/1.2962992 |title=Bits on Quantum Information |archive-url=https://web.archive.org/web/20230111183353/https://physicstoday.scitation.org/doi/10.1063/1.2962992 |archive-date=January 11, 2023 |url-status=live |magazine=Physics Today |date=July 2008 |volume=61 |issue=7 |last=Jaeger |first=Greg |page=10 |doi=10.1063/1.2962992}}</ref>{{refn|The letter was in response to a review of his book ''Quantum Information: An Overview'', that had questioned "whether there is an audience for such encyclopedic texts, especially given the easy access to online sources of information such as the [[arXiv]] e-print server and Wikipedia."|group=nb}}

People known to use or recommend Wikipedia as a reference source include [[film critic]] [[Roger Ebert]],<ref>{{Cite book|url=https://archive.org/details/rogerebertsmovie00roge_0|url-access=registration|author=Ebert, Roger|title=Roger Ebert's Movie Yearbook 2009|publisher=Andrews McMeel Publishing|page =[https://archive.org/details/rogerebertsmovie00roge_0/page/529 529] |date= November 18, 2008|isbn=978-0-7407-7745-5}}</ref><ref>Ebert, Roger (October 7, 2009). [http://rogerebert.suntimes.com/apps/pbcs.dll/article?AID=/20091007/REVIEWS/910079997 Review of ''Good Hair''] {{Webarchive|url=https://web.archive.org/web/20121221122846/http://rogerebert.suntimes.com/apps/pbcs.dll/article?AID=%2F20091007%2FREVIEWS%2F910079997 |date=December 21, 2012 }}. [[RogerEbert.com]].</ref><ref>Ebert, Roger. [http://blogs.suntimes.com/ebert/2011/01/post_4.html "Why 3D doesn't work and never will. Case closed."] {{Webarchive|url=https://web.archive.org/web/20110501035944/http://blogs.suntimes.com/ebert/2011/01/post_4.html |date=May 1, 2011 }} ''[[Chicago Sun-Times]]''. January 23, 2011</ref><ref>Ebert, Roger. [http://rogerebert.suntimes.com/apps/pbcs.dll/article?AID=/20110622/REVIEWS/110629991/1001/reviews "The Last Mountain"] {{Webarchive|url=https://web.archive.org/web/20121221122817/http://rogerebert.suntimes.com/apps/pbcs.dll/article?AID=%2F20110622%2FREVIEWS%2F110629991%2F1001%2Freviews |date=December 21, 2012 }}, rogerebert.com, June 22, 2011</ref> comedian [[Rosie O'Donnell]],<ref>Hall, Sarah. [http://www.eonline.com/uberblog/b54017_rosie_vs_donald_she_said_said.html "Rosie vs. Donald: She Said, He Said"] {{Webarchive|url=https://web.archive.org/web/20110426035427/http://www.eonline.com/uberblog/b54017_rosie_vs_donald_she_said_said.html |date=April 26, 2011 }}, [[E! Online]], December 21, 2006</ref> [[University of Maryland]] [[physicist]] [[Robert L. Park]],<ref>{{cite web|url=http://bobpark.physics.umd.edu/WN09/wn082809.html|first=Robert L.|last=Park|title=What's New|date=August 28, 2009|publisher=bobpark.org|access-date=July 13, 2010|archive-url=https://web.archive.org/web/20091003003518/http://bobpark.physics.umd.edu/WN09/wn082809.html|archive-date=October 3, 2009|url-status=dead|author-link=Robert L. Park}}</ref> [[Rutgers University]] sociology professor Ted Goertzel<ref>{{cite journal | last1 = Goertzel | first1 = Ted | year = 2011 | title = Letters to the Editor: Conspiracy Thinking | journal = [[Skeptical Inquirer]] | volume = 35 | issue = 3| page = 64 }}</ref><ref>"The Conspiracy Meme" (January/February 2011). ''Skeptical Inquirer''. Vol. 35 No. 1. January/February 2011. p. 37</ref> and [[scientific skepticism]] promoter and investigator [[James Randi]].<ref>{{cite web|author=Randi, James|date=March 18, 2012|publisher=[[James Randi Educational Foundation]]|title=Popoff's Still At It|url=http://www.randi.org/site/index.php/swift-blog/1660-popoffs-still-at-it.html|access-date=March 22, 2012|archive-url=https://web.archive.org/web/20120320170823/http://www.randi.org/site/index.php/swift-blog/1660-popoffs-still-at-it.html|archive-date=March 20, 2012|url-status=live|author-link=James Randi}}</ref> Periodicals that publish articles featuring citations of Wikipedia as a source include the American science magazines ''[[Skeptic (U.S. magazine)|Skeptic]]''<ref>{{cite journal | last1 = Hillshafer | first1 = David | year = 2013 | title = The Mass Murder Problem | journal = [[Skeptic (U.S. magazine)|Skeptic]] | volume = 18 | issue = 1| pages = 24–32 }}</ref><ref>[[Jim Lippard|Lippard, Jim]] (2012). "The Decline and (Probable) Fall of the Scientology Empire!". ''Skeptic'' Vol. 17 No. 1. pp. 18–27. The citations in question are Citations 10, 14 and 16, as seen on page 27.</ref> and ''[[Skeptical Inquirer]]''.<ref>{{cite journal | last1 = Sheaffer | first1 = Robert | year = 2014 | title = Between a Beer Joint and a Highway Warning Sign: The 'Classic' Cash-Landrum Case Unravels". "Psychic Vibrations" | journal = [[Skeptical Inquirer]] | volume = 38 | issue = 2| page = 28 }}</ref> In the January 2013 episode of his talk show, ''[[Stossel (TV series)|Stossel]]'', about how ideas can flourish without regulation, journalist [[John Stossel]] interviewed Wikipedia co-founder Jimmy Wales, and discussed the success of Wikipedia's model versus that of Britannica, during which Stossel stated that [[John Stossel|his own Wikipedia article]] exhibited only one error.<ref>[http://www.foxbusiness.com/on-air/stossel/index.html#/v/2071803797001/wikipedia-defies-need-for-regulation/?playlist_id=87530 "Wikipedia Defies Need for Regulation"] {{Webarchive|url=https://web.archive.org/web/20150506071103/http://www.foxbusiness.com/on-air/stossel/index.html#/v/2071803797001/wikipedia-defies-need-for-regulation/?playlist_id=87530 |date=May 6, 2015 }}. ''[[Stossel (TV series)|Stossel]]''. [[Fox Business]]. January 4, 2013.</ref>

Jean Goodwin wrote on the reasons why Wikipedia may be trusted. According to him, while readers may not assess the actual expertise of the authors of a given article, they may assess the passion of Wikipedians, and in so far provide a reason for trust.<ref>Goodwin, Jean. (2010). The authority of Wikipedia. In Juho Ritola (Ed.), Argument cultures: Proceedings of the Ontario Society for the Study of Argumentation Conference. Windsor, ON, Canada: Ontario Society for the Study of Argumentation. CD-ROM. 24 pp.<!-- Available online at http://scholar.uwindsor.ca/cgi/viewcontent.cgi?article=1144&context=ossaarchive --></ref><!-- This paper asks an interesting question. The first 2 chapters are interesting are relatively accessible, exploring the reasons why one might trust Wikipedia. I find the third chapter, where the author finds a reason for trust, less convincing. Not too sure this should be kept as is. Chealer 2015 -->

[[Dariusz Jemielniak]], a Wikimedia Foundation Board of Trustees member, suggested in 2019 that given the arrival of Wikipedia's 18th birthday, "maybe academics should start treating it as an adult".<ref>{{cite journal |last1=Jemielniak |first1=Dariusz |title=Wikipedia: Why Is the Common Knowledge Resource Still Neglected by Academics? |journal=GigaScience |date=2019 |volume=8 |issue=12|doi=10.1093/gigascience/giz139 |pmid=31794014 |pmc=6889752 }}</ref>

== Notable incidents ==
{{see also|List of Wikipedia controversies}}

=== False biographical information ===
<!-- Deleted image removed: [[File:Astran.JPG|thumb|upright=1.4|Cached version of a deleted biographical hoax in the French Wikipedia. Created in January 2007, the article on the fictional 18th-century naturalist Léon Robert de L'Astran was not deleted until June 2010, when a historian identified it as a hoax.<ref name="lemonde.fr">[http://www.lemonde.fr/politique/article/2010/06/07/quand-segolene-royal-cite-un-personnage-historique-qui-n-a-jamais-existe_1369150_823448.html "Ségolène Royal et Léon-Robert de l'Astran, le savant qui n'a jamais existé"] {{Webarchive|url=https://web.archive.org/web/20100607185314/http://www.lemonde.fr/politique/article/2010/06/07/quand-segolene-royal-cite-un-personnage-historique-qui-n-a-jamais-existe_1369150_823448.html |date=June 7, 2010 }}, ''[[Le Monde]]'', June 7, 2010</ref>]] -->

Inaccurate information may persist in Wikipedia for a long time before it is challenged. The most prominent cases reported by mainstream media involved biographies of living persons. The [[Wikipedia biography controversy|Seigenthaler incident]] demonstrated that the subject of a biographical article must sometimes fix blatant lies about his or her own life. In May 2005, a user edited the [[biography|biographical]] article on [[John Seigenthaler Sr.]] so that it contained several false and [[defamation|defamatory]] statements.<ref name=SeigenthalerUSAToday>{{cite news|url=https://www.usatoday.com/news/opinion/editorials/2005-11-29-wikipedia-edit_x.htm|work=USA Today|date=November 29, 2005|title=A false Wikipedia "biography"|first=John|last=Seigenthaler|access-date=September 10, 2017|archive-url=https://web.archive.org/web/20120106225139/http://www.usatoday.com/news/opinion/editorials/2005-11-29-wikipedia-edit_x.htm|archive-date=January 6, 2012|url-status=live|author-link=John Seigenthaler}}</ref> The inaccurate claims went unnoticed between May and September 2005 when they were discovered by [[Victor S. Johnson, Jr.]], a friend of Seigenthaler. Wikipedia content is often mirrored at sites such as [[Answers.com]], which means that incorrect information can be replicated alongside correct information through a number of web sources. Such information can develop a misleading air of authority because of its presence at such sites: "Then [Seigenthaler's] son discovered that his father's hoax biography also appeared on two other sites, Reference.com and Answers.com, which took direct feeds from Wikipedia. It was out there for four months before Seigenthaler realized and got the Wikipedia entry replaced with a more reliable account. The lies remained for another three weeks on the mirror sites downstream."<ref name=SeigenthalerABC>{{cite web|url=http://www.abc.net.au/radionational/programs/scienceshow/mistakes-and-hoaxes-on-line/3330692|title=Mistakes and hoaxes on-line|publisher=Australian Broadcasting Corporation|date=April 15, 2006|access-date=April 28, 2007|archive-url=https://web.archive.org/web/20121113084903/http://www.abc.net.au/radionational/programs/scienceshow/mistakes-and-hoaxes-on-line/3330692|archive-date=November 13, 2012|url-status=live}}</ref>

Seth Finkelstein reported in an article in ''[[The Guardian]]'' on his efforts to remove his own biography page from Wikipedia, simply because it was subjected to [[defamation]]: "Wikipedia has a short biography of me, originally added in February 2004, mostly concerned with my internet civil liberties achievements. After discovering in May 2006 that it had been vandalised in March, possibly by a long-time opponent, and that the attack had been subsequently propagated to many other sites which (legally) repackage Wikipedia's content, the article's existence seemed to me overall to be harmful rather than helpful." He added: "For people who are not very prominent, Wikipedia biographies can be an '[[attractive nuisance]]'. It says, to every troll, vandal, and score-settler: 'Here's an article about a person where you can, with no accountability whatsoever, write any libel, defamation, or smear. It won't be a marginal comment with the social status of an inconsequential rant, but rather will be made prominent about the person, and reputation-laundered with the institutional status of an encyclopedia.{{'"}}<ref>Seth Finkelstein (September 28, 2006) [https://www.theguardian.com/technology/2006/sep/28/wikipedia.web20 "I'm on Wikipedia, get me out of here"] {{Webarchive|url=https://web.archive.org/web/20161112180917/https://www.theguardian.com/technology/2006/sep/28/wikipedia.web20 |date=November 12, 2016 }} The Guardian. Inside IT.</ref>

In the same article, Finkelstein recounts how he voted his own biography as "not [[Notability in Wikipedia|notable]] enough" in order to have it removed from Wikipedia. He goes on to recount a similar story involving Angela Beesley, previously a prominent member of the foundation which runs Wikipedia. [[Taner Akçam]], a [[Turkish people|Turkish]] history professor at the [[University of Minnesota]], was detained at the Montreal airport, as his article was vandalized by Turkish nationalists in 2007. While this mistake was resolved, he was again arrested in US for the same suspicion two days later.<ref>{{cite magazine | url=http://www.time.com/time/specials/packages/article/0,28804,2042333_2042334_2042574,00.html | magazine=Time | title=Top 10 Wikipedia Moments | date=January 13, 2011 | access-date=August 21, 2011 | archive-url=https://web.archive.org/web/20110824015545/http://www.time.com/time/specials/packages/article/0,28804,2042333_2042334_2042574,00.html | archive-date=August 24, 2011 | url-status=dead }}</ref>

On March 2, 2007, MSNBC reported that [[Hillary Clinton]] had been incorrectly listed for 20 months in her Wikipedia biography as [[valedictorian]] of her class of 1969 at [[Wellesley College]]. (Hillary Rodham was not the valedictorian, though she did speak at [[Graduation|commencement]].)<ref>{{cite news|first=Bill|last=Dedman|url=https://www.nbcnews.com/id/wbna17388372|title=Reading Hillary Clinton's hidden thesis|publisher=NBC News|date=March 3, 2007|access-date=March 17, 2007|archive-date=July 12, 2020|archive-url=https://web.archive.org/web/20200712085245/http://www.nbcnews.com/id/17388372|url-status=live}}</ref> The article included a link to the Wikipedia edit,<ref>{{cite web|url=http://en.wikipedia.org/w/index.php?title=Hillary_Rodham_Clinton&diff=18494301&oldid=18493966|title=Hillary Rodham Clinton|publisher=Wikipedia|date=July 9, 2005|access-date=March 17, 2007|archive-url=https://web.archive.org/web/20160216104215/https://en.wikipedia.org/w/index.php?title=Hillary_Rodham_Clinton&diff=18494301&oldid=18493966|archive-date=February 16, 2016|url-status=live}}</ref> where the incorrect information was added on July 9, 2005. After the msnbc.com report, the inaccurate information was removed the same day.<ref>{{cite web|url=http://en.wikipedia.org/w/index.php?title=Hillary_Rodham_Clinton&diff=112070224&oldid=111773323|title=Hillary Rodham Clinton|publisher=Wikipedia|date=March 2, 2007|access-date=March 17, 2007|archive-url=https://web.archive.org/web/20160216104216/https://en.wikipedia.org/w/index.php?title=Hillary_Rodham_Clinton&diff=112070224&oldid=111773323|archive-date=February 16, 2016|url-status=live}}</ref>{{refn|Between the two edits, the wrong information had stayed in the Clinton article while it was edited more than 4,800 times over 20 months.|group=nb}}

Attempts to perpetrate [[hoax]]es may not be confined to editing Wikipedia articles. In October 2005 [[Alan Mcilwraith]], a former [[call center]] worker from Scotland created a Wikipedia article in which he claimed to be a highly decorated war hero. The article was quickly identified by other users as unreliable (see [[Wikipedia:Wikipedia Signpost/2006-04-17/Persistent hoax|''Wikipedia Signpost'' article April 17, 2006]]); however, Mcilwraith had also succeeded in convincing a number of charities and media organizations that he was who he claimed to be: "The 28-year-old, who calls himself Captain Sir Alan McIlwraith, KBE, DSO, MC, has mixed with celebrities for at least one fundraising event. But last night, an Army spokesman said: 'I can confirm he is a fraud. He has never been an officer, soldier or Army cadet.{{'"}}<ref>{{cite news |url=http://www.dailyrecord.co.uk/news/tm_objectid=16929538&method=full&siteid=66633&headline=meet-sir-walter-mitty--name_page.html |title=Exclusive: Meet the Real Sir Walter Mitty |first=Cara |last=Paige |newspaper=Daily Record |date=April 11, 2006 |access-date=November 24, 2007 |url-status=dead |archive-url=https://web.archive.org/web/20070930014712/http://www.dailyrecord.co.uk/news/tm_objectid%3D16929538%26method%3Dfull%26siteid%3D66633%26headline%3Dmeet-sir-walter-mitty--name_page.html |archive-date=September 30, 2007 }}</ref>

In May 2010, French politician [[Ségolène Royal]] publicly praised the memory of Léon-Robert de l'Astran, an 18th-century [[naturalist]], [[humanist]] and son of a slave trader, who had opposed the slave trade. The newspaper ''[[Sud-Ouest (newspaper)|Sud-Ouest]]'' revealed a month later that de l'Astran had never existed—except as the subject of an article in the [[French Wikipedia]]. Historian Jean-Louis Mahé discovered that de l'Astran was fictional after a student, interested by Royal's praise of him, asked Mahé about him. Mahé's research led him to realize that de l'Astran did not exist in any archives, and he traced the hoax back to the [[Rotary Club]] of [[La Rochelle]]. The article, created by members of the Club in January 2007, had thus remained online for three years—unsourced—before the hoax was uncovered. Upon ''Sud-Ouest'''s revelation—repeated in other major French newspapers—French Wikipedia administrator [[:fr:Utilisateur:DonCamillo|DonCamillo]] immediately deleted the article.<ref name="TimesFrenchWPHoax">{{cite news | url=http://www.thetimes.co.uk/tto/news/world/europe/article2547291.ece | title=Ségolène Royal and Wikipedia duped by tale of anti-slavery activist | work=[[The Times]] | date=June 9, 2010 | access-date=June 17, 2011 | location=London | first=Adam | last=Sage | archive-url=https://web.archive.org/web/20140728232255/http://www.thetimes.co.uk/tto/news/world/europe/article2547291.ece | archive-date=July 28, 2014 | url-status=dead | df=mdy-all }}</ref><ref name="lemonde.fr">[http://www.lemonde.fr/politique/article/2010/06/07/quand-segolene-royal-cite-un-personnage-historique-qui-n-a-jamais-existe_1369150_823448.html "Ségolène Royal et Léon-Robert de l'Astran, le savant qui n'a jamais existé"] {{Webarchive|url=https://web.archive.org/web/20100607185314/http://www.lemonde.fr/politique/article/2010/06/07/quand-segolene-royal-cite-un-personnage-historique-qui-n-a-jamais-existe_1369150_823448.html |date=June 7, 2010 }}, ''[[Le Monde]]'', June 7, 2010</ref><ref>[http://www.sudouest.fr/2010/06/07/leon-robert-de-l-astran-celui-qui-n-a-jamais-existe-110539-3415.php "Léon-Robert de L'Astran, celui qui n'a jamais existé"] {{Webarchive|url=https://web.archive.org/web/20100611054014/http://www.sudouest.fr/2010/06/07/leon-robert-de-l-astran-celui-qui-n-a-jamais-existe-110539-3415.php |date=June 11, 2010 }}, ''[[Sud-Ouest (newspaper)|Sud-Ouest]]'', June 7, 2010</ref><ref>[http://www.lefigaro.fr/politique/2010/06/08/01002-20100608ARTFIG00346-segolene-royal-tombe-dans-le-piege-de-wikipedia.php "Ségolène Royal tombe dans le piège de Wikipédia"] {{Webarchive|url=https://web.archive.org/web/20100610235048/http://www.lefigaro.fr/politique/2010/06/08/01002-20100608ARTFIG00346-segolene-royal-tombe-dans-le-piege-de-wikipedia.php |date=June 10, 2010 }}, ''[[Le Figaro]]'', June 8, 2010</ref><ref>[http://www.lejdd.fr/Politique/Actualite/Royal-toute-une-Histoire-198776/ "Royal, toute une Histoire"] {{Webarchive|url=https://web.archive.org/web/20100610024220/http://www.lejdd.fr/Politique/Actualite/Royal-toute-une-Histoire-198776/ |date=June 10, 2010 }}, ''[[Le Journal du Dimanche]]'', June 7, 2010</ref><ref>{{Cite web|url=http://fr.wikipedia.org/wiki/L%C3%A9on_Robert_de_L%27Astran |title=Léon Robert de L'Astran |archive-url=https://web.archive.org/web/20060913000000/https://fr.wikipedia.org/wiki/L%C3%A9on_Robert_de_L'Astran |archive-date=September 13, 2006 |url-status=live}}, article in the French Wikipedia, deleted on June 7, 2010</ref>

There have also been instances of users deliberately inserting false information into Wikipedia in order to test the system and demonstrate its alleged unreliability. Journalist [[Gene Weingarten]] ran such a test in 2007 by anonymously inserting false information into his own biography. The fabrications were removed 27 hours later by a Wikipedia editor who was regularly watching changes to that article.<ref>{{cite news|first=Gene|last=Weingarten|date=March 16, 2007|url=http://www.newsobserver.com/105/story/553968.html|title=A wickedly fun test of Wikipedia|newspaper=[[The News & Observer]]|access-date=April 8, 2006 |archive-url = https://web.archive.org/web/20070320032706/http://www.newsobserver.com/105/story/553968.html |archive-date = March 20, 2007}}</ref> Television personality [[Stephen Colbert]] lampooned this drawback of Wikipedia, calling it [[Wikipedia in popular culture#Wikiality|wikiality]].<ref>{{cite web |last1=McCarthy |first1=Caroline |title=Colbert speaks, America follows: All hail Wikiality! |url=https://www.cnet.com/culture/colbert-speaks-america-follows-all-hail-wikiality/ |website=[[CNET]] |access-date=November 17, 2022 |date=August 1, 2006 |archive-date=November 17, 2022 |archive-url=https://web.archive.org/web/20221117083359/https://www.cnet.com/culture/colbert-speaks-america-follows-all-hail-wikiality/ |url-status=live }}</ref>

"Death by Wikipedia" is a phenomenon in which a person is erroneously proclaimed dead through vandalism. Articles about the comedian [[Paul Reiser]], British television host [[Vernon Kay]], French professor [[Bertrand Meyer#Wikipedia hoax|Bertrand Meyer]], and the West Virginia Senator [[Robert Byrd]], who died on June 28, 2010, have been vandalized in this way.<ref>{{cite web |last=Metz |first=Cade |url=https://www.theregister.co.uk/2009/01/22/wikipedia_vandalism_crackdown/ |title=Jimbo Wales ends death by Wikipedia |work=The Register |date=January 22, 2009 |access-date=March 31, 2010 |archive-url=https://web.archive.org/web/20100427134821/http://www.theregister.co.uk/2009/01/22/wikipedia_vandalism_crackdown/ |archive-date=April 27, 2010 |url-status=live }}</ref><ref>{{cite web |last=Goss |first=Patrick |url=http://www.techradar.com/news/internet/vernon-kay-shocked-at-death-by-wikipedia-464838 |title=Vernon Kay shocked at death by Wikipedia |publisher=Techradar.com |date=September 15, 2008 |access-date=March 31, 2010 |archive-url=https://web.archive.org/web/20110519230124/http://www.techradar.com/news/internet/vernon-kay-shocked-at-death-by-wikipedia-464838 |archive-date=May 19, 2011 |url-status=live }}</ref><ref>{{Cite news |last=Pershing |first=Ben |url=http://voices.washingtonpost.com/capitol-briefing/2009/01/kennedy_the_latest_victim_of_w.html?hpid=topnews |title=Kennedy, Byrd the Latest Victims of Wikipedia Errors |newspaper=The Washington Post |date=January 21, 2009 |access-date=May 31, 2011 |archive-url=https://web.archive.org/web/20110811014259/http://voices.washingtonpost.com/capitol-briefing/2009/01/kennedy_the_latest_victim_of_w.html?hpid=topnews |archive-date=August 11, 2011 |url-status=dead }}</ref>{{refn|Wikipedia considers vandalism as "any addition, removal, or change of content in a deliberate attempt to compromise the integrity of Wikipedia". The Wikipedia page "[[Wikipedia:Researching with Wikipedia|Researching with Wikipedia]]" states: "Wikipedia's radical openness means that any given article may be, at any given moment, in a bad state: for example, it could be in the middle of a large edit or it could have been recently vandalized. While blatant vandalism is usually easily spotted and rapidly corrected, Wikipedia is certainly more subject to subtle vandalism than a typical reference work."|group=nb}}

=== Other false information ===
In June 2007, an anonymous Wikipedia contributor became involved in the [[Chris Benoit double murder and suicide]] because of an unverified piece of information he added to the "[[Chris Benoit]]" [[English Wikipedia]] article. This information regarding Benoit's wife's death was added fourteen hours before police discovered the bodies of Benoit and his family.<ref>{{cite news |first=Blane |last=Bachelor |title=Web Time Stamps Indicate Benoit Death Reported About 14 Hours Before Police Found Bodies |url=http://www.foxnews.com/story/0,2933,287194,00.html |publisher=[[Fox News]] |date=June 28, 2007 |access-date=May 21, 2008 |archive-url=https://web.archive.org/web/20080517070950/http://www.foxnews.com/story/0,2933,287194,00.html |archive-date=May 17, 2008 |url-status=dead}}</ref> Police detectives seized computer equipment from the man held responsible for the postings, but believed he was uninvolved and did not press charges.<ref name="hindrance">{{cite news |first=David |last=Schoetz |title=Police: Wiki Confession an 'Unbelievable Hindrance' |url=https://abcnews.go.com/Sports/story?id=3327310&page=1 |publisher=[[ABC News (United States)|ABC News]] |date=June 29, 2007 |access-date=May 21, 2008 |archive-url=https://web.archive.org/web/20080516121016/https://abcnews.go.com/Sports/story?id=3327310&page=1 |archive-date=May 16, 2008 |url-status=live}}</ref> The [[IP address]] from which the edit was made was traced to earlier instances of Wikipedia vandalism. The contributor apologized on [[Wikinews]], saying: "I will never vandalize anything on Wikipedia or post wrongful information. I will never post anything here again unless it is pure fact ... ."<ref>{{cite news |title=The College Student Who 'Knew' About the Benoit Murder-Suicide Before Police |first=Corey |last=Spring |url=http://spring.newsvine.com/_news/2007/06/29/808872-the-college-student-who-knew-about-the-benoit-murder-suicide-before-police |date=June 29, 2007 |access-date=May 21, 2008 |publisher=[[Newsvine]] |archive-url=https://web.archive.org/web/20160911094254/http://spring.newsvine.com/_news/2007/06/29/808872-the-college-student-who-knew-about-the-benoit-murder-suicide-before-police |archive-date=September 11, 2016 |url-status=live}}</ref>

On August 29, 2008, shortly after the first round draw was completed for [[UEFA Europa League]] football cup, an edit about a nickname of the fans was made to the article for the football club [[AC Omonia]], apparently by users of the website [[B3ta]].<ref>[http://www.webuser.co.uk/news/news.php?id=268155 Mirror duped by Wikipedia 'fact'] {{Webarchive|url=https://web.archive.org/web/20220217233024/http://subscribe.webuser.co.uk/?id=268155 |date=February 17, 2022}} (''Web User'', September 19, 2008)</ref>{{refn|It added the following erroneous information to the section titled "The fans": "A small but loyal group of fans are lovingly called "The Zany Ones"—they like to wear hats made from discarded shoes and have a song about a little potato."|group=nb}} On September 18, 2008, David Anderson, a British journalist writing for the ''[[Daily Mirror]]'', quoted this in his match preview ahead of Omonia's game with [[Manchester City F.C.|Manchester City]], which appeared in the web and print versions of the ''Mirror'' and the nickname was quoted in subsequent editions on September 19.<ref>{{cite web |url=https://www.mirror.co.uk/sport/football/2008/09/18/new-look-manchester-city-side-begin-their-uefa-cup-campaign-in-earnest-115875-20741334/ |title=New-look Manchester City side begin their UEFA Cup campaign in earnest |work=Daily Mirror |date=September 18, 2008 |access-date=April 13, 2010 |archive-url=https://web.archive.org/web/20090819104710/http://www.mirror.co.uk/sport/football/2008/09/18/new-look-manchester-city-side-begin-their-uefa-cup-campaign-in-earnest-115875-20741334/ |archive-date=August 19, 2009 |url-status=live}}</ref><ref>{{cite web |url=https://www.mirror.co.uk/sport/football/match-reports/2008/09/19/omonia-nicosia-1-2-manchester-city-goals-start-to-flow-for-jo-115875-20743824/ |title=Omonia Nicosia 1–2 Manchester City: Goals start to flow for Jo |work=Daily Mirror |date=April 9, 2010 |access-date=April 13, 2010 |archive-url=https://web.archive.org/web/20090813164321/http://www.mirror.co.uk/sport/football/match-reports/2008/09/19/omonia-nicosia-1-2-manchester-city-goals-start-to-flow-for-jo-115875-20743824/ |archive-date=August 13, 2009 |url-status=live}}</ref>

In May 2009, [[University College Dublin]] sociology student Shane Fitzgerald added an incorrect quote to the article on the recently deceased composer [[Maurice Jarre]]. Fitzgerald wanted to demonstrate the potential dangers of news reporters' reliance on the internet for information.<ref>{{cite news |url=http://www.irishtimes.com/newspaper/opinion/2009/0507/1224246059241.html |title=Lazy journalism exposed by online hoax |date=May 7, 2009 |first=Shane |last=Fitzgerald |newspaper=[[The Irish Times]] |access-date=January 8, 2010 |archive-url=https://web.archive.org/web/20111101125154/http://www.irishtimes.com/newspaper/opinion/2009/0507/1224246059241.html |archive-date=November 1, 2011 |url-status=live  }}</ref> Although Fitzgerald's edits were removed three times from the Wikipedia article for [[Wikipedia:Verifiability#Responsibility for providing citations|lack of sourcing]],<ref name=ABC>{{cite web |url=https://abcnews.go.com/Technology/AheadoftheCurve/wirestory?id=7556738&page=1 |title=Irish Student Hoaxes World's Media With Fake Quote |publisher=[[ABC News (United States)|ABC News]] |first=Shawn |last=Pogatchnik |date=May 11, 2009 |access-date=January 8, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20110628211245/https://abcnews.go.com/Technology/AheadoftheCurve/wirestory?id=7556738&page=1 |archive-date=June 28, 2011 }}</ref> they were nevertheless copied into obituary columns in newspapers worldwide.<ref>{{cite web |url=https://arstechnica.com/media/news/2009/05/wikipedia-hoax-reveals-limits-of-journalists-research.ars |title=Wikipedia hoax points to limits of journalists' research |date=May 8, 2009 |publisher=arstechnica.com |access-date=January 8, 2010 |archive-url=https://web.archive.org/web/20100221221444/http://arstechnica.com/media/news/2009/05/wikipedia-hoax-reveals-limits-of-journalists-research.ars |archive-date=February 21, 2010 |url-status=live}}</ref> Fitzgerald believes that if he had not come forward his quote would have remained in history as fact.<ref name=ABC/>

After the [[2010 FIFA World Cup]], FIFA president [[Sepp Blatter]] was presented with the Order of the Companions of Oliver Reginald Tambo. The citation, however, read: "The Order of the Companions of OR Tambo in Gold—awarded to Joseph Sepp [[wikt:bellend|Bellend]] Blatter (1936–) for his exceptional contribution to the field of football and support for the hosting of the Fifa World Cup on the African continent", after the name on his Wikipedia entry was vandalized.<ref>{{cite news |url=http://www.metro.co.uk/sport/oddballs/835201-sepp-blatter-called-a-bellend-during-award-of-south-african-medal |title=Sepp Blatter called a 'bellend' during award of South African medal |work=The Metro|date=July 15, 2010 |access-date=August 11, 2010 |archive-url=https://web.archive.org/web/20100806080420/http://www.metro.co.uk/sport/oddballs/835201-sepp-blatter-called-a-bellend-during-award-of-south-african-medal |archive-date=August 6, 2010 |url-status=dead}}</ref>

The death of [[Norman Wisdom]] in October 2010 led several major newspapers to repeat the false claim, drawn from Wikipedia, that he was the author of the lyrics of the Second World War song "[[(There'll Be Bluebirds Over) The White Cliffs of Dover]]".<ref>{{cite news |url=https://www.theguardian.com/media/mediamonkeyblog/2010/oct/05/norman-wisdom-wikipedia-mirror |title='Wikipedia vandals' strike again in Norman Wisdom obits |newspaper=[[The Guardian]] |date=October 5, 2010 |access-date=December 3, 2010 |location=London |archive-url=https://web.archive.org/web/20160116210933/http://www.theguardian.com/media/mediamonkeyblog/2010/oct/05/norman-wisdom-wikipedia-mirror |archive-date=January 16, 2016 |url-status=live}}</ref>

In October 2012, the [[Asian Football Confederation]] official website published an article about the [[United Arab Emirates national football team]]'s bid to qualify for the 2015 AFC Asian Cup, in which the team's nickname was stated to be the "Sand Monkeys". This was the indirect result of vandalism of the Wikipedia article on the team, and the AFC was forced to apologise for what was perceived as a racist slur.<ref>{{cite news |url=https://sports.yahoo.com/blogs/soccer-dirty-tackle/asian-football-confederation-apologize-calling-uae-national-team-182949385--sow.html |title=Asian Football Confederation apologize for calling UAE national team 'Sand Monkeys' |last=Bailey |first=Ryan |publisher=Yahoo! Sports |date=October 25, 2012 |access-date=March 25, 2014 |archive-url=https://web.archive.org/web/20140325192044/http://sports.yahoo.com/blogs/soccer-dirty-tackle/asian-football-confederation-apologize-calling-uae-national-team-182949385--sow.html |archive-date=March 25, 2014 |url-status=live}}</ref><ref>{{cite news |url=http://www.cbsnews.com/news/asian-soccer-body-apologizes-for-sand-monkeys-slur-of-uae-team/ |title=Asian soccer body apologizes for 'sand monkeys' slur of UAE team |agency=Associated Press |publisher=CBS News |date=October 15, 2012 |access-date=March 25, 2014 |archive-url=https://web.archive.org/web/20140325191605/http://www.cbsnews.com/news/asian-soccer-body-apologizes-for-sand-monkeys-slur-of-uae-team/ |archive-date=March 25, 2014 |url-status=live}}</ref>

[[File:A photo of the Wikipedia hoax "Bicholim conflict".jpeg|thumb|The [[Wikipedia:List of hoaxes on Wikipedia|Wikipedia hoax]] "Bicholim conflict"<ref name="Bicholim original">{{self-reference link|Wikipedia:List of hoaxes on Wikipedia/Bicholim conflict|Archived copy of article at time of deletion}}</ref> which in 2007 won the status of "Good Article"]]
In December 2012, an article titled "Bicholim conflict"<ref name="Bicholim original"/> was deleted after standing since 2007.<ref name="Bicholim Deletion">{{cite web|title=Wikipedia:Articles for deletion/Bicholim conflict|url=https://en.wikipedia.org/w/index.php?title=Wikipedia:Articles_for_deletion/Bicholim_conflict&oldid=530321030|publisher=Wikipedia|access-date=May 22, 2013|archive-date=February 17, 2022|archive-url=https://web.archive.org/web/20220217233023/https://en.wikipedia.org/w/index.php?title=Wikipedia%3AArticles_for_deletion%2FBicholim_conflict&oldid=530321030|url-status=live}}</ref> It talked about a war that took place in India between the years 1640 and 1641, but was later confirmed to be completely fictitious.<ref>{{cite news|last=Pfeiffer |first=Eric |title=War is over: Imaginary 'Bicholim Conflict' page removed from Wikipedia after five years |url=https://news.yahoo.com/blogs/sideshow/war-over-imaginary-bicholim-conflict-page-removed-wikipedia-234717353.html |access-date=January 8, 2013 |publisher=[[Yahoo! News]] |date=January 4, 2013 |archive-url=https://web.archive.org/web/20130109103905/http://news.yahoo.com/blogs/sideshow/war-over-imaginary-bicholim-conflict-page-removed-wikipedia-234717353.html |archive-date=January 9, 2013 |url-status=live}}</ref> The hoax article had won Wikipedia's "Good Article" award, a status conferred on fewer than 1 percent of articles on the site, a few months after its creation in 2007, and held that status for five years.<ref>{{cite news |url=http://www.dailydot.com/news/wikipedia-bicholim-conflict-hoax-deleted/ |last=Morris |first=Kevin |title=After a half-decade, massive Wikipedia hoax finally exposed |work=The Daily Dot |date=January 1, 2013 |access-date=March 25, 2014 |archive-url=https://web.archive.org/web/20140410195455/http://www.dailydot.com/news/wikipedia-bicholim-conflict-hoax-deleted/ |archive-date=April 10, 2014 |url-status=live }}</ref>

In March 2013, it was discovered that both Wikipedia and [[IMDb]] had for three-and-a-half years contained articles on a fictitious Russian filmmaker named Yuri Gadyukin. False information had been planted in both sites as part of a viral promotion campaign for an upcoming film.<ref>{{cite news |url=http://www.dailydot.com/entertainment/wikipedia-hoax-yuri-gadyukin-nitrate-movie/ |last=Morris |first=Kevin |title=The greatest movie that never was |work=The Daily Dot |date=April 25, 2013 |access-date=March 25, 2014 |archive-url=https://web.archive.org/web/20130426183336/http://www.dailydot.com/entertainment/wikipedia-hoax-yuri-gadyukin-nitrate-movie/ |archive-date=April 26, 2013 |url-status=live }}</ref>

In May 2014, ''[[The New Yorker]]'' reported that a 17-year-old student had added an invented nickname to the Wikipedia article on the [[coati]] in 2008, saying coatis were also known as "Brazilian [[aardvark]]s". The taxonomically false information, inserted as a private joke, lasted for six years in Wikipedia and over this time came to be propagated by hundreds of websites, several newspapers (one of which was later cited as a source in Wikipedia) and even books published by university presses. It was only removed from Wikipedia after publication of the ''New Yorker'' article, in which the student explained how the joke had come about.<ref name=NewYorker_May19_2014/><ref name=RegisterKolbe/>

In March 2015, it became known that an article on Wikipedia entitled "[[Jar'Edo Wens hoax|Jar'Edo Wens]]", purportedly about an Australian aboriginal deity of that name, was a hoax. The article had survived for more than nine years before being deleted, making it one of the longest-lived documented hoax articles in Wikipedia's history. The article spawned mentions of the fake god on numerous other websites as well as in a book titled ''Atheism and the Case Against Christ''.<ref>{{cite news |url=https://www.washingtonpost.com/news/the-intersect/wp/2015/04/15/the-great-wikipedia-hoax/ |title=The story behind Jar'Edo Wens, the longest-running hoax in Wikipedia history |newspaper=The Washington Post |date=April 15, 2015 |access-date=April 19, 2015 |author=Dewey, Caitlin |archive-url=https://web.archive.org/web/20150419001603/http://www.washingtonpost.com/news/the-intersect/wp/2015/04/15/the-great-wikipedia-hoax/ |archive-date=April 19, 2015 |url-status=live}}</ref><ref>{{cite web|url=http://www.smh.com.au/digital-life/digital-life-news/aussies-jaredo-wens-prank-sets-new-record-as-wikipedias-longestrunning-hoax-20150323-1m59c7.html|title=Aussie's Jar'Edo Wens prank sets new record as Wikipedia's longest-running hoax|work=The Sydney Morning Herald|date=March 23, 2015|access-date=July 8, 2015|archive-url=https://web.archive.org/web/20150701152353/http://www.smh.com.au/digital-life/digital-life-news/aussies-jaredo-wens-prank-sets-new-record-as-wikipedias-longestrunning-hoax-20150323-1m59c7.html|archive-date=July 1, 2015|url-status=live}}</ref><ref>{{cite web|url=http://internet.gawker.com/how-one-man-made-himself-into-an-aboriginal-god-with-wi-1692426415 |title=How One Man Made Himself Into an Aboriginal God With Wikipedia |first=Andy |last=Cush |publisher=Gawker Media |work=Weird Internet |url-status=dead |archive-url=https://web.archive.org/web/20150709193621/http://internet.gawker.com/how-one-man-made-himself-into-an-aboriginal-god-with-wi-1692426415 |archive-date=July 9, 2015}}</ref>

In August 2019, a discredited theory was removed from the article [[Warsaw concentration camp]], over 10 years after [[Fringe theory|it was debunked in mainstream scholarly literature]]. The article was first drafted in August 2004 by an established editor who presented as fact [[Warsaw concentration camp#Discredited extermination camp story|a fringe theory that the camp contained gas chambers in which 200,000 people perished]]. With the [[misinformation]] presented as fact for 15 years, media sources dubbed it as "Wikipedia's longest-standing hoax".<ref>{{cite news |work=[[Haaretz]] |url=https://www.haaretz.com/israel-news/.premium.MAGAZINE-the-fake-nazi-death-camp-wikipedia-s-longest-hoax-exposed-1.7942233 |title=The Fake Nazi Death Camp: Wikipedia's Longest Hoax, Exposed |date=October 4, 2019 |first=Omer |last=Benjakob |access-date=December 29, 2021 |archive-date=October 19, 2019 |archive-url=https://web.archive.org/web/20191019175407/https://www.haaretz.com/israel-news/.premium.MAGAZINE-the-fake-nazi-death-camp-wikipedia-s-longest-hoax-exposed-1.7942233 |url-status=live}}</ref><ref>{{cite news|title=Wikipedia's 'longest-running hoax' about fake Warsaw death camp revealed|newspaper=[[Cleveland Jewish News]]|url=https://www.clevelandjewishnews.com/jns/wikipedia-s-longest-running-hoax-about-fake-warsaw-death-camp/article_856e66a1-0289-5e77-a73f-219a00536c54.html|date=October 4, 2019|access-date=December 29, 2021|archive-date=November 24, 2021|archive-url=https://web.archive.org/web/20211124182412/https://www.clevelandjewishnews.com/jns/wikipedia-s-longest-running-hoax-about-fake-warsaw-death-camp/article_856e66a1-0289-5e77-a73f-219a00536c54.html|url-status=live}}</ref><ref>{{cite news|title= Wikipedia page on fake Warsaw concentration camp was 15-year hoax — report|newspaper=[[The Times of Israel]]|url=https://www.timesofisrael.com/wikipedia-page-on-fake-warsaw-concentration-camp-was-15-year-hoax-report/|date= October 5, 2019|access-date=December 29, 2021|archive-date=November 7, 2021|archive-url=https://web.archive.org/web/20211107183051/https://www.timesofisrael.com/wikipedia-page-on-fake-warsaw-concentration-camp-was-15-year-hoax-report/|url-status=live}}</ref>

In June 2022, it was discovered that an editor known as Zhemao ({{lang-zh|折毛}}) had created over 200 articles on the Chinese Wikipedia about fabricated events in medieval [[Russian history]].<ref>{{Cite news|url=https://www.vice.com/en/article/chinese-woman-fake-russian-history-wikipedia/|title=A Bored Chinese Housewife Spent Years Falsifying Russian History on Wikipedia|work=Vice News|date=July 13, 2022|access-date=July 13, 2022|archive-date=July 17, 2022|archive-url=https://web.archive.org/web/20220717231705/https://www.vice.com/en/article/pkgbwm/chinese-woman-fake-russian-history-wikipedia|url-status=live}}</ref> Dubbed the [[Zhemao hoaxes]], the hoax articles combined research and fantasy, creating an [[alternate history]] centered around a "[[Kashin (town)|Kashin]] silver mine" and political ties between "princes of Tver" and "dukes of Moscow".<ref>{{cite web |last1=Diamond |first1=Jonny |title=A "Chinese Borges" wrote millions of words of fake Russian history on Wikipedia for a decade. |url=https://lithub.com/a-chinese-borges-wrote-millions-of-words-of-fake-russian-history-on-wikipedia-for-a-decade/ |website=Literary Hub |access-date=August 6, 2022 |date=June 28, 2022 |archive-date=July 17, 2022 |archive-url=https://web.archive.org/web/20220717130111/https://lithub.com/a-chinese-borges-wrote-millions-of-words-of-fake-russian-history-on-wikipedia-for-a-decade/ |url-status=live}}</ref>

{{anchor|Alan MacMasters}}In August 2022, Wikipedia criticism site [[Wikipediocracy]] published an interview with a hoaxer who ten years prior had added a hoax to Wikipedia, claiming that an "[[Alan MacMasters hoax|Alan MacMasters]]" had invented the [[electric toaster]]. The false information was widely reproduced online as well as in newspapers and books subsequently cited in Wikipedia.<ref>{{cite news |url=http://bbc.co.uk/news/the-reporters-63622746 |title=Alan MacMasters: How the great online toaster hoax was exposed |agency=BBC News |date=November 19, 2022 |access-date=November 20, 2022 |archive-date=November 20, 2022 |archive-url=https://web.archive.org/web/20221120143621/https://www.bbc.co.uk/news/the-reporters-63622746 |url-status=live}}</ref><ref>{{Cite web |title=Wikipedia's Credibility Is Toast {{!}} Wikipediocracy |url=https://wikipediocracy.com/2022/08/11/wikipedias-credibility-is-toast/ |access-date=September 11, 2022 |website=wikipediocracy.com |archive-date=September 4, 2022 |archive-url=https://web.archive.org/web/20220904071848/https://wikipediocracy.com/2022/08/11/wikipedias-credibility-is-toast/ |url-status=live }}</ref><ref>{{Cite web |last=Rauwerda |first=Annie |title=A long-running Wikipedia hoax and the problem of circular reporting |url=https://www.inputmag.com/culture/wikipedia-hoax-alan-macmasters-toaster |access-date=September 11, 2022 |website=Input |date=August 12, 2022 |language=en |archive-date=September 4, 2022 |archive-url=https://web.archive.org/web/20220904072741/https://www.inputmag.com/culture/wikipedia-hoax-alan-macmasters-toaster |url-status=live}}</ref>

In 2023, [[Jan Grabowski]] and Shira Klein published an article in the ''[[The Journal of Holocaust Research|Journal of Holocaust Research]]'' in which they claim to have discovered a "systematic, intentional distortion of Holocaust history" on the English-language Wikipedia.<ref name="Holocaust_2023">{{Cite journal |last1=Grabowski |first1=Jan |last2=Klein |first2=Shira |date=February 9, 2023 |title=Wikipedia's Intentional Distortion of the History of the Holocaust |journal=The Journal of Holocaust Research |volume=37 |issue=2 |pages=133–190 |doi=10.1080/25785648.2023.2168939 |s2cid=257188267 |issn=2578-5648 |doi-access=free}}</ref> Analysing 25 Wikipedia articles and almost 300 back pages (including talk pages, noticeboards and arbitration cases), Grabowski and Klein believe they have shown how a small group of editors managed to impose a fringe narrative on Polish–Jewish relations, informed by Polish nationalist propaganda and far removed from evidence-driven historical research. Supposed nationalist editing on these and other articles allegedly included content ranging "from minor errors to subtle manipulations and outright lies", examples of which the authors offer.<ref name="Holocaust_2023" /> A response to Grabowski and Klein's article, which argues that their main conclusions are misleading or false, was published by Piotr Konieczny in the journal [[Holocaust Studies (journal)|Holocaust Studies]] in 2025.<ref>{{cite journal | author = Piotr Konieczny | title = Fake news, an internet troll, and a conspiracy theory about ‘Wikipedia's Intentional Distortion of the History of the Holocaust’ | journal = Holocaust Studies | year = 2025 | doi = 10.1080/17504902.2025.2511459 | at = Published online 5 June 2025 | url = https://drive.google.com/file/d/1nCcu0CtD18MjXI-iEq-R7MuMGlx4zxdv/view}}</ref>

=== Conflict-of-interest editing on Wikipedia ===
{{main|Conflict-of-interest editing on Wikipedia}}

==== Political interests and advocacy ====
While Wikipedia policy requires articles to have a neutral point of view, there have been attempts to place a [[spin (public relations)|spin]] on articles. In January 2006 several staffers of members of the [[U.S. House of Representatives]] attempted to cleanse their respective bosses' biographies on Wikipedia, and to insert negative remarks on political opponents. References to a campaign promise by [[Marty Meehan|Martin Meehan]] to surrender his seat in 2000 were deleted, and negative comments were inserted into the articles on U.S. Senator [[Bill Frist]] and [[Eric Cantor]], a congressman from [[Virginia]]. Numerous other changes were made from an [[IP address]] which is assigned to the House of Representatives.<ref>{{cite web|first=Margaret|last=Kane|date=January 30, 2006|url=http://news.cnet.com/2061-11199_3-6032713.html|title=Politicians notice Wikipedia|website=[[CNET|Cnet news.com]]|access-date=January 28, 2007|archive-url=https://web.archive.org/web/20160311014348/http://www.cnet.com/news/politicians-notice-wikipedia/|archive-date=March 11, 2016}}</ref> In an interview, Jimmy Wales remarked that the changes were "not cool".<ref>{{cite web|url=http://lawnorder.blogspot.com/2006/01/senator-staffers-spam-wikipedia.html|title=Senator staffers spam Wikipedia|access-date=September 13, 2006|archive-url=https://web.archive.org/web/20060329061323/http://lawnorder.blogspot.com/2006/01/senator-staffers-spam-wikipedia.html|archive-date=March 29, 2006|url-status=live}}</ref>

On August 31, 2008, ''The New York Times'' ran an article detailing the edits made to the biography of [[Sarah Palin]] in the wake of her nomination as running mate of [[John McCain]]. During the 24 hours before the McCain campaign announcement, 30 edits, many of them flattering details, were made to the article by Wikipedia single-purpose user identity Young Trigg. This person later acknowledged working on the McCain campaign, and having several Wikipedia user accounts.<ref>Noam Cohen (August 31, 2008) [https://www.nytimes.com/2008/09/01/technology/01link.html?ex=1378008000&en=2690a3850cb270d0&ei=5124&partner=permalink&exprod=permalink "Don't Like Palin's Wikipedia Story? Change It"] {{Webarchive|url=https://web.archive.org/web/20180228041708/http://www.nytimes.com/2008/09/01/technology/01link.html?ex=1378008000&en=2690a3850cb270d0&ei=5124&partner=permalink&exprod=permalink |date=February 28, 2018 }} Technology. ''The New York Times''.</ref><ref>[http://www.thaindian.com/newsportal/india-news/sarah-palins-wikipedia-entry-glossed-over-by-mystery-user-hrs-before-vp-announcement_10091497.html "Sarah Palins Wikipedia entry glossed over by mystery user hrs. before VP announcement"] {{Webarchive|url=https://web.archive.org/web/20110524085649/http://www.thaindian.com/newsportal/india-news/sarah-palins-wikipedia-entry-glossed-over-by-mystery-user-hrs-before-vp-announcement_10091497.html |date=May 24, 2011 }}, ''Thaindian News'' (September 2, 2008)</ref>

Larry Delay and Pablo Bachelet write that from their perspective, some articles dealing with Latin American history and groups (such as the [[Sandinista National Liberation Front|Sandinistas]] and [[Cuba]]) lack political neutrality and are written from a sympathetic Marxist perspective which treats socialist dictatorships favorably at the expense of alternate positions.<ref>{{Cite news|first=Pablo|last=Bachelet|url=http://nl.newsbank.com/nl-search/we/Archives?p_product=MH&p_theme=mh&p_action=search&p_maxdocs=200&s_dispstring=cuba%20wikipedia%20AND%20date(all)&p_field_advanced-0=&p_text_advanced-0=(cuba%20wikipedia)&p_sort=_rank_:D&xcal_ranksort=4&xcal_useweights=yes|title=War of Words: Website Can't Define Cuba|date=May 3, 2006|work=[[The Miami Herald]]|access-date=July 8, 2008|archive-url=https://web.archive.org/web/20121222150122/http://nl.newsbank.com/nl-search/we/Archives?p_product=MH&p_theme=mh&p_action=search&p_maxdocs=200&s_dispstring=cuba%20wikipedia%20AND%20date(all)&p_field_advanced-0=&p_text_advanced-0=(cuba%20wikipedia)&p_sort=_rank_:D&xcal_ranksort=4&xcal_useweights=yes|archive-date=December 22, 2012|url-status=live}}</ref><ref>{{cite web|first=Larry|last=Delay|url=http://lanic.utexas.edu/project/asce/pdfs/volume16/pdfs/program.pdf|title=A Pernicious Model for Control of the World Wide Web: The Cuba Case|date=August 3, 2006|publisher=Association for Study of the Cuban Economy(ASCE)|access-date=July 8, 2008|archive-url=https://web.archive.org/web/20080910014641/http://lanic.utexas.edu/project/asce/pdfs/volume16/pdfs/program.pdf|archive-date=September 10, 2008|url-status=dead}}</ref>

In November 2007, libelous accusations were made against two politicians from southwestern France, [[Jean-Pierre Grand]] and [[Hélène Mandroux-Colas]], on their Wikipedia biographies. Jean-Pierre Grand asked the president of the [[French National Assembly]] and the [[prime minister of France]] to reinforce the legislation on the penal responsibility of Internet sites and of authors who peddle false information in order to cause harm.<ref>[http://www.vnunet.fr/fr/news/2007/11/28/wikipedia_en_butte_a_une_nouvelle_affaire_de_calomnie "Wikipédia en butte à une nouvelle affaire de calomnie"] {{webarchive |url=https://web.archive.org/web/20080516003915/http://www.vnunet.fr/fr/news/2007/11/28/wikipedia_en_butte_a_une_nouvelle_affaire_de_calomnie |date=May 16, 2008 }}, Vnunet.fr, 28 novembre 2007.</ref> Senator [[Jean-Louis Masson (politician, 1947)|Jean Louis Masson]] then requested the Minister of Justice to tell him whether it would be possible to increase the criminal responsibilities of hosting providers, site operators, and authors of libelous content; the minister declined to do so, recalling the existing rules in the [[:fr:Loi pour la confiance dans l'économie numérique|LCEN]] law.<ref>{{cite web |url-status=live |url=http://www.senat.fr/questions/base/2007/qSEQ071102679.html |title=Responsabilité pénale des intervenants sur Internet : hébergeur du site, responsable du site et auteur d'allégations diffamatoires |archive-url=https://web.archive.org/web/20110721022032/http://www.senat.fr/questions/base/2007/qSEQ071102679.html |archive-date=July 21, 2011 |first1=Jean-Louis |last1=Masson |date=November 29, 2007 |website=Sénat }}</ref>

In 2009, Wikipedia banned the [[Church of Scientology]] from editing any articles on its site. The Wikipedia articles concerning Scientology were edited by members of the group to improve its portrayal.<ref>{{cite news|url=http://www.mid-day.com/lifestyle/2009/jun/030609-Wikipedia-Controversy-Church-of-Scientology-IT-Adda-Bangalore.htm|title=Handling controversy on Wikipedia|first=Balaji|last=Narasimhan|newspaper=[[MiD DAY]]|date=June 3, 2009|access-date=November 7, 2011|archive-url=https://web.archive.org/web/20111026012205/http://www.mid-day.com/lifestyle/2009/jun/030609-Wikipedia-Controversy-Church-of-Scientology-IT-Adda-Bangalore.htm|archive-date=October 26, 2011|url-status=dead }}</ref>

On August 25, 2010, the ''[[Toronto Star]]'' reported that the Canadian "government is now conducting two investigations into federal employees who have taken to Wikipedia to express their opinion on federal policies and bitter political debates."<ref>{{cite news |url=https://www.thestar.com/news/canada/article/852228--ottawa-investigating-wikipedia-edits |title=Ottawa investigating Wikipedia edits |first=Allan |last=Woods |date=August 25, 2010 |newspaper=[[Toronto Star]] |access-date=August 26, 2010 |archive-url=https://web.archive.org/web/20100827182851/http://www.thestar.com/news/canada/article/852228--ottawa-investigating-wikipedia-edits |archive-date=August 27, 2010 |url-status=dead }}</ref>

In 2010, [[Al Jazeera Media Network|Al Jazeera]]'s Teymoor Nabili suggested that the article ''[[Cyrus Cylinder]]'' had been edited for political purposes by "an apparent tussle of opinions in the shadowy world of hard drives and 'independent' editors that comprise the Wikipedia industry." He suggested that after the [[Iranian presidential election, 2009]] and the ensuing "anti-Iranian activities" a "strenuous attempt to portray the cylinder as nothing more than the propaganda tool of an aggressive invader" was visible. The edits following his analysis of the edits during 2009 and 2010, represented "a complete dismissal of the suggestion that the cylinder, or Cyrus' actions, represent concern for human rights or any kind of enlightened intent", in stark contrast to [[Cyrus the Great|Cyrus]]' own reputation (among the people of Babylon) as written in the [[Old Testament]].<ref>{{cite web |first=Teymoor |last=Nabili |url=http://blogs.aljazeera.net/middle-east/2010/09/11/cyrus-cylinder-wikipedia-and-iran-conspiracies |title=The Cyrus Cylinder, Wikipedia and Iran conspiracies |publisher=Al Jazeera Blogs |date=September 11, 2010 |access-date=March 19, 2012 |archive-url=https://web.archive.org/web/20120311004844/http://blogs.aljazeera.net/middle-east/2010/09/11/cyrus-cylinder-wikipedia-and-iran-conspiracies |archive-date=March 11, 2012 |url-status=dead }}</ref>

===== Arab–Israeli conflict =====
{{See also|Wikipedia and the Israeli–Palestinian conflict}}
In April 2008, the Boston-based Committee for Accuracy in Middle East Reporting in America ([[Committee for Accuracy in Middle East Reporting in America|CAMERA]]) organized an e-mail campaign to encourage readers to correct perceived Israel-related biases and inconsistencies in Wikipedia.<ref>Metz, Cade, "[https://www.theregister.co.uk/2008/04/29/wikipedia_blocked_doj_ip/ US Department of Justice banned from Wikipedia] {{Webarchive|url=https://web.archive.org/web/20170810140158/https://www.theregister.co.uk/2008/04/29/wikipedia_blocked_doj_ip/ |date=2017-08-10 }}, ''The Register'', April 29, 2008.</ref> Excerpts of some of the e-mails were published in the July 2008 issue of ''[[Harper's Magazine]]'' under the title of "Candid camera".<ref name="Harpers">{{cite magazine|url=http://harpers.org/archive/2008/07/0082086/|title=Candid camera|magazine=[[Harper's Magazine]]|date=July 2008|access-date=May 31, 2011|archive-url=https://web.archive.org/web/20110615131311/http://harpers.org/archive/2008/07/0082086/|archive-date=June 15, 2011|url-status=live}}</ref>

CAMERA argued the excerpts were unrepresentative and that it had explicitly campaigned merely "toward encouraging people to learn about and edit the online encyclopedia for accuracy".<ref>{{cite web |url=http://www.camera.org/index.asp?x_context=2&x_outlet=32&x_article=1525 |title=Letter in Harper's Magazine About Wikipedia Issues |publisher=Camera |date=August 14, 2008 |access-date=March 31, 2010 |archive-url=https://web.archive.org/web/20100615234849/http://camera.org/index.asp?x_context=2&x_outlet=32&x_article=1525 |archive-date=June 15, 2010 |url-status=live }}</ref> According to some defenders of CAMERA, serious misrepresentations of CAMERA's role emanated from the competing [[Electronic Intifada]] group; moreover, it is said, some other Palestinian advocacy groups have been guilty of systematic misrepresentations and manipulative behaviors but have not suffered bans of editors amongst their staff or volunteers.<ref>{{cite web |first=Andre |last=Oboler |title=Exposed – Anti-Israel Subversion on Wikipedia |date=May 14, 2008 |work=Media Critiques |url=http://www.honestreporting.com/articles/45884734/critiques/new/Exposed_-_Anti-Israeli_Subversion_on_Wikipedia.asp |access-date=May 31, 2011 |archive-url=https://web.archive.org/web/20100316193353/http://honestreporting.com/articles/45884734/critiques/new/Exposed_-_Anti-Israeli_Subversion_on_Wikipedia.asp |archive-date=March 16, 2010 |url-status=dead  }}</ref><ref>{{cite news |first=Andre |last=Oboler |title=Wiki Warfare: Battle for the on-line encyclopedia |date= May 13, 2008 |newspaper=The Jerusalem Post |url=http://www.jpost.com/Opinion/Op-EdContributors/Article.aspx?id=101037|archive-url=https://web.archive.org/web/20110629014224/http://www.jpost.com/Opinion/Op-EdContributors/Article.aspx?id=101037|url-status=dead|archive-date=June 29, 2011}}</ref>

Five editors involved in the campaign were sanctioned by Wikipedia administrators.<ref name="Telegraph">{{Cite news|url=https://www.telegraph.co.uk/news/1934857/Israeli-battles-rage-on-Wikipedia.html|title=Israeli battles rage on Wikipedia|work=[[The Daily Telegraph]]|access-date=May 8, 2008|date=May 8, 2008|last=McElroy|first=Damien|location=London|archive-url=https://web.archive.org/web/20080509185630/http://www.telegraph.co.uk/news/1934857/Israeli-battles-rage-on-Wikipedia.html|archive-date=May 9, 2008|url-status=live}}</ref> Israeli diplomat David Saranga said that Wikipedia is generally fair in regard to Israel. When confronted with the fact that the entry on Israel mentioned the word "occupation" nine times, whereas the entry on the Palestinian people mentioned "terror" only once, he replied: "It means only one thing: Israelis should be more active on Wikipedia. Instead of blaming it, they should go on the site much more, and try and change it."<ref>[http://www.haaretz.com/culture/arts-leisure/your-wiki-entry-counts-1.235851 Your wiki entry counts] {{Webarchive|url=https://web.archive.org/web/20110605071013/http://www.haaretz.com/culture/arts-leisure/your-wiki-entry-counts-1.235851 |date=June 5, 2011 }}, Haaretz, By Cnaan Liphshiz 25.12.07</ref>

Political commentator Haviv Rettig Gur, reviewing widespread perceptions in Israel of systemic bias in the English-language Wikipedia articles, has argued that there are deeper structural problems creating this bias: anonymous editing favors biased results, especially if those Gur calls "pro-Palestinian activists" organize concerted campaigns as has been putatively done in articles dealing with Arab-Israeli issues, and current Wikipedia policies, while well-meant, have proven ineffective in handling this.<ref>{{cite news |first=Haviv Rettig |last=Gur |title=Israeli-Palestinian conflict rages on Wikipedia |newspaper=The Jerusalem Post |date=May 16, 2010 |url=http://www.jpost.com/Israel/Article.aspx?id=175660 |access-date=May 31, 2011 |archive-url=https://web.archive.org/web/20110629014308/http://www.jpost.com/Israel/Article.aspx?id=175660 |archive-date=June 29, 2011 |url-status=live  }}</ref>

On August 3, 2010, it was reported that the Yesha Council together with Israel Sheli (My Israel), a network of online pro-Israel activists committed to spreading Zionism online, were organizing people at a workshop in [[Jerusalem]] to teach them how to edit Wikipedia articles in a pro-Israeli way.<ref name="Guardian1">{{Cite news|title=Wikipedia editing courses launched by Zionist groups|first1=Rachel|last1=Shabi|first2=Jemima|last2=Kiss|newspaper=The Guardian|date=August 18, 2010|url=https://www.theguardian.com/world/2010/aug/18/wikipedia-editing-zionist-groups|location=London|access-date=December 16, 2016|archive-url=https://web.archive.org/web/20130819031910/http://www.theguardian.com/world/2010/aug/18/wikipedia-editing-zionist-groups|archive-date=August 19, 2013|url-status=live}}</ref><ref>{{Cite news | last=Benari | first=Elad | title=Zionist Internet Struggle to Hit Wikipedia | url=http://www.israelnationalnews.com/News/News.aspx/138917 | publisher=Arutz Sheva | date=August 3, 2010 | access-date=August 18, 2010 | archive-url=https://web.archive.org/web/20100821104221/http://www.israelnationalnews.com/News/news.aspx/138917 | archive-date=August 21, 2010 | url-status=live }}</ref><ref name="Haaretz"/> Around 50 people took part in the course.<ref name="Haaretz">{{cite web |last=Hasson |first=Nir |url=http://www.haaretz.com/print-edition/news/the-right-s-latest-weapon-zionist-editing-on-wikipedia-1.308667 |url-access=subscription |title=The right's latest weapon: 'Zionist editing' on Wikipedia |work=Haaretz |date=March 12, 2012 |access-date=March 19, 2012 |archive-url=https://web.archive.org/web/20120524042839/http://www.haaretz.com/print-edition/news/the-right-s-latest-weapon-zionist-editing-on-wikipedia-1.308667 |archive-date=May 24, 2012 |url-status=live }}</ref>

The project organiser, [[Ayelet Shaked]], who has since been elected to Israel's parliament, was interviewed on [[Arutz Sheva|Arutz Sheva Radio]]. She emphasized that the information has to be reliable and meet Wikipedia rules. She cited some examples such as the use of the term "occupation" in Wikipedia entries, as well as in the editing of entries that link Israel with [[Judea and Samaria]] and [[Jewish history]]".<ref name="sheva">{{cite web |last=Benari |first=Elad |url=http://www.israelnationalnews.com/News/News.aspx/138917 |title=Zionist Internet Struggle to Hit Wikipedia |publisher=Arutz Sheva |date=March 8, 2010 |access-date=March 19, 2012 |archive-url=https://web.archive.org/web/20111211114634/http://www.israelnationalnews.com/News/News.aspx/138917 |archive-date=December 11, 2011 |url-status=live  }}</ref>

"We don't want to change Wikipedia or turn it into a propaganda arm," commented [[Naftali Bennett]], director of the Yesha Council. "We just want to show the other side. People think that Israelis are mean, evil people who only want to hurt Arabs all day."<ref name="ynet">{{cite news |url=http://www.ynetnews.com/articles/0,7340,L-3944937,00.html |title=The battle for Wikipedia: Palestinians counter Israeli editing group |newspaper=Ynetnews |date=June 20, 1995 |access-date=March 19, 2012 |archive-url=https://web.archive.org/web/20120108163334/http://www.ynetnews.com/articles/0,7340,L-3944937,00.html |archive-date=January 8, 2012 |url-status=live }}</ref> "The idea is not to make Wikipedia rightist but for it to include our point of view," he said in another interview.<ref name=Haaretz/>

A course participant explained that the course is not a "Zionist conspiracy to take over Wikipedia"; rather, it is an attempt to balance information about disputed issues presented in the online encyclopedia.
<blockquote>[T]he goal of this workshop was to train a number of pro-Israelis how to edit Wikipedia so that more people could present the Israeli side of things, and thus the content would be more balanced... Wikipedia is meant to be a fair and balanced source, and it is that way by having people from all across the spectrum contributing to the content.<ref>[http://thelede.blogs.nytimes.com/2010/08/23/readers-discuss-wikipedia-editing-course-that-aims-for-balanced-and-zionist-entries/ "Readers Discuss Wikipedia Editing Course That Aims for 'Balanced and Zionist' Entries"] {{Webarchive|url=https://web.archive.org/web/20120509071716/http://thelede.blogs.nytimes.com/2010/08/23/readers-discuss-wikipedia-editing-course-that-aims-for-balanced-and-zionist-entries/ |date=May 9, 2012 }} By Robert Mackey August 23, 2010, 1:12 p.m.</ref></blockquote>

Following the course announcement, Abdul Nasser An-Najar, the head of Palestinian Journalists Syndicate said there were plans to set up a counter group to ensure the Palestinian view is presented online as the "next regional war will be [a] media war."<ref name="ynet"/>

In 2011, Wikipedia founder Jimmy Wales stated in retrospect about the course organized by Israel Sheli, "we saw absolutely no impact from that effort whatsoever. I don't think it ever—it was in the press but we never saw any impact."<ref>[http://www.haaretz.com/news/national/wikipedia-founder-israel-palestine-is-heavily-debated-but-we-re-vigilant-on-neutrality-1.377207 Wikipedia founder: Israel-Palestine is heavily debated, but we're vigilant on neutrality] {{Webarchive|url=https://web.archive.org/web/20120529110910/http://www.haaretz.com/news/national/wikipedia-founder-israel-palestine-is-heavily-debated-but-we-re-vigilant-on-neutrality-1.377207 |date=May 29, 2012 }}, Haaretz</ref>

==== Editing for financial rewards ====
In an October 2012 ''[[Salon (website)|Salon]]'' story, Wikipedia co-founder Jimmy Wales stated that he was against the practice of paid editing of Wikipedia, as are a number long-time members of Wikipedia's community. Nonetheless, a number of organizations do pay employees to edit Wikipedia articles, with one writer, Soraya Field Fiorio, stating that she writes commissioned Wikipedia articles for writers and musicians for $30 an hour. According to Fiorio, her clients control the article's content in the same way that they control press releases, which function as part of publicity strategies.<ref>Ewing, Maura (October 23, 2012). [http://www.salon.com/2012/10/23/is_wikipedia_going_commercial/ "Is Wikipedia going commercial?"] {{Webarchive|url=https://web.archive.org/web/20130616063338/http://www.salon.com/2012/10/23/is_wikipedia_going_commercial/ |date=June 16, 2013 }}. [[Salon (website)|Salon]].</ref> In January 2007, Rick Jelliffe claimed in a story carried by [[CBS]]<ref name="mscbs">[[Brian Bergstein]] (January 24, 2007) [https://web.archive.org/web/20070203093103/http://www.cbsnews.com/stories/2007/01/24/tech/main2392719.shtml Microsoft Violates Wikipedia's Sacred Rule] The Associated Press. Archived from [https://web.archive.org/web/20070203093103/http://www.cbsnews.com/stories/2007/01/24/tech/main2392719.shtml the original] on June 4, 2011.<!--Oddly, the current live version of this article is now dated February 11, 2009, long after this took place--></ref> and [[International Data Group|IDG]] News Service<ref name="msidg1">Nancy Gohring (January 23, 2007) [http://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9008842 "Microsoft said to offer payment for Wikipedia edits"] {{Webarchive|url=https://web.archive.org/web/20090517023639/http://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9008842 |date=May 17, 2009 }} IDG News Service. Retrieved September 3, 2008.</ref><ref name="msidg2">Nancy Gohring [http://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9008842 "Microsoft's step into Wikipedia prompts debate"] {{Webarchive|url=https://web.archive.org/web/20090517023639/http://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9008842 |date=May 17, 2009 }} IDG News Service.</ref> that [[Microsoft]] had offered him compensation in exchange for his future editorial services on [[OOXML]]. A Microsoft spokesperson, quoted by CBS, commented that "Microsoft and the writer, Rick Jelliffe, had not determined a price and no money had changed hands, but they had agreed that the company would not be allowed to review his writing before submission".

In a story covered by the [[BBC]], Jeffrey Merkey claimed that in exchange for a donation his Wikipedia entry was edited in his favor. Jay Walsh, a spokesman for Wikipedia, flatly denied the allegations in an interview given to the ''[[Daily Telegraph]]''.<ref>March 12, 2008 [http://news.bbc.co.uk/2/hi/technology/7291382.stm Wiki boss 'edited for donation'] {{Webarchive|url=https://web.archive.org/web/20080728030443/http://news.bbc.co.uk/2/hi/technology/7291382.stm |date=July 28, 2008 }} Technology. BBC News.</ref>

In a story covered by ''[[InformationWeek]]'', [[Eric Goldman]], assistant [[law]] professor at [[Santa Clara University]] in [[California]] argued that "eventually, marketers will build scripts to edit Wikipedia pages to insert links and conduct automated attacks on Wikipedia",<ref>{{cite web|url=http://blog.ericgoldman.org/archives/2005/12/wikipedia_will.htm|first=Eric|last=Goldman|title=Wikipedia Will Fail Within 5 Years|date=December 5, 2005|access-date=January 16, 2010|archive-url=https://web.archive.org/web/20100105223616/http://blog.ericgoldman.org/archives/2005/12/wikipedia_will.htm|archive-date=January 5, 2010|url-status=live}}</ref> thus putting the encyclopedia beyond the ability of its editors to provide [[countermeasure]]s against the attackers, particularly because of a [[virtuous circle and vicious circle|vicious circle]] where the strain of responding to these attacks drives core contributors away, increasing the strain on those who remain.<ref>{{cite magazine|url=http://www.informationweek.com/internet/showArticle.jhtml?articleID=196601766|first=Thomas|last=Claburn|title=Law Professor Predicts Wikipedia's Demise|magazine=[[InformationWeek]]|date=December 5, 2006|access-date=December 16, 2006|archive-url=https://web.archive.org/web/20070905103606/http://www.informationweek.com/internet/showArticle.jhtml?articleID=196601766|archive-date=September 5, 2007|url-status=live}}</ref>{{refn|Wikipedia operates [[Wikipedia:Bots|bots]] to aid in the detection and removal of vandalism, and uses [[nofollow]] and a [[CAPTCHA]] to discourage and filter additions of external links.|group=nb}}

===== Conflicts involving Wikipedia policy makers =====
In February 2008, British technology news and opinion website ''[[The Register]]'' stated that a prominent administrator of Wikipedia had edited a topic area where he had a conflict of interest to keep criticism to a bare minimum, as well as altering the Wikipedia policies regarding ''personal biography'' and ''conflict of interest'' to favour his editing.<ref>{{cite news |last1=Metz |first1=Cade |title=Wikipedia ruled by 'Lord of the Universe' |url=https://www.theregister.com/2008/02/06/the_cult_of_wikipedia/ |access-date=January 22, 2023 |work=The Register |date=February 6, 2008 |language=en |archive-date=January 22, 2023 |archive-url=https://web.archive.org/web/20230122073136/https://www.theregister.com/2008/02/06/the_cult_of_wikipedia/ |url-status=live }}</ref>

Some of the most scathing criticism of Wikipedia's claimed neutrality came in ''The Register'', which in turn was allegedly criticized by founding members of the project. According to ''The Register'': "In short, Wikipedia is a cult. Or at least, the inner circle is a cult. We aren't the first to make this observation. On the inside, they reinforce each other's beliefs. And if anyone on the outside questions those beliefs, they circle the wagons. They deny the facts. They attack the attacker. After our Jossi Fresco story, Fresco didn't refute our reporting. He simply accused us of 'yellow journalism'. After our Overstock.com article, Wales called us 'trash'."<ref>Cade Metz (March 6, 2008). "[https://www.theregister.co.uk/2008/03/06/a_model_wikipedian/page2.html Why you should care that Jimmy Wales ignores reality] {{Webarchive|url=https://web.archive.org/web/20121220230900/http://www.theregister.co.uk/2008/03/06/a_model_wikipedian/page2.html |date=December 20, 2012 }}". The Register. Retrieved April 27, 2010.</ref>

Charles Arthur in ''The Guardian'' said that "Wikipedia, and so many other online activities, show all the outward characteristics of a [[cult]]."<ref name="cult">{{cite news | url = http://technology.guardian.co.uk/online/insideit/story/0,,1667345,00.html | title = Log on and join in, but beware the web cults | last = Arthur | first = Charles | date = December 15, 2005 | access-date = July 14, 2006 | work = The Guardian | location = London | archive-url = https://web.archive.org/web/20060503042626/http://technology.guardian.co.uk/online/insideit/story/0,,1667345,00.html | archive-date = May 3, 2006 | url-status = live }}</ref>

In February 2015, a longstanding Wikipedia administrator was site-banned after Wikipedia's [[Arbitration Committee (Wikipedia)|Arbitration Committee]] found that they had, over a period of several years, manipulated the content of Wikipedia articles to add positive content and remove negative content about the controversial [[Indian Institute of Planning and Management]] and its dean, [[Arindam Chaudhuri]]. An Indian journalist commented in ''Newsweek'' on the importance of the Wikipedia article to the institute's PR campaign and voiced the opinion that "by letting this go on for so long, Wikipedia has messed up perhaps 15,000 students' lives".<ref>{{cite web|url=http://www.newsweek.com/2015/04/03/manipulating-wikipedia-promote-bogus-business-school-316133.html|title=Manipulating Wikipedia to Promote a Bogus Business School|first=Alastair Sloan On 3/24/15 at 12:20|last=PM|date=March 24, 2015|website=Newsweek|access-date=July 8, 2015|archive-url=https://web.archive.org/web/20150703213410/http://www.newsweek.com/2015/04/03/manipulating-wikipedia-promote-bogus-business-school-316133.html|archive-date=July 3, 2015|url-status=live}}</ref><ref>{{cite web|url=http://scroll.in/article/714291/Wikipedia-bans-editor-for-consistent-bias-in-favour-of-Arindam-Chaudhuri's-IIPM|title=Wikipedia bans editor for consistent bias in favour of Arindam Chaudhuri's IIPM|first=Mridula|last=Chari|work=Scroll.in|date=March 25, 2015 |access-date=July 8, 2015|archive-url=https://web.archive.org/web/20150430081559/http://scroll.in/article/714291/Wikipedia-bans-editor-for-consistent-bias-in-favour-of-Arindam-Chaudhuri%27s-IIPM|archive-date=April 30, 2015|url-status=live}}</ref>

==== Scientific disputes ====
The 2005 ''Nature'' study also gave two brief examples of challenges that Wikipedian science writers purportedly faced on Wikipedia. The first concerned the addition of a section on violence to the [[Schizophrenia#Violence|schizophrenia]] article, which exhibited the view of one of the article's regular editors, [[neuropsychologist]] [[Vaughan Bell]], that it was little more than a "rant" about the need to lock people up, and that editing it stimulated him to look up the literature on the topic.<ref name="GilesJ2005Internet"/>

The second dispute reported by ''Nature'' involved the climatologist [[William Connolley]] related to protracted disputes between editors of climate change topics, in which Connolley was placed on parole and several opponents banned from editing climate related articles for six months;<ref name="GilesJ2005Internet"/> a separate paper commented that this was more about etiquette than bias and that Connolley did "not [[suffer fools gladly]]".<ref name="crowdsourcing">{{cite journal |first=Mathieu |last=O'Neil |url=http://jcom.sissa.it/archive/09/01/Jcom0901(2010)C01/Jcom0901(2010)C04 |title=Shirky and Sanger, or the costs of crowdsourcing |publisher=Journal of Science Communication |volume=09 |issue=1 |date=March 2010 |journal=International School for Advanced Studies |access-date=May 31, 2011 |archive-url=https://web.archive.org/web/20110429151027/http://jcom.sissa.it/archive/09/01/Jcom0901(2010)C01/Jcom0901(2010)C04 |archive-date=April 29, 2011 |url-status=live }}</ref>

== See also ==
<!-- Please avoid repeating links already in the article, per WP:ALSO -->
{{columns-list|colwidth=20em|
* ''[[Bourgeois v. Peters]]'' (2004), one of the earliest court opinions to cite and quote Wikipedia
* [[Essjay controversy]]
* [[Fictitious entry]]
* [[Ideological bias on Wikipedia]]
* [[Wikipedia:List of hoaxes on Wikipedia]]
* ''[[The Truth According to Wikipedia]]'' (2008)
* ''[[Truth in Numbers?]]'' (2010)
* [[WikiTrust]], a [[reputation system]] for Wikipedia authors and content
* [[Woozle effect]]
'''In other Wikipedias'''
* {{Slink|Dutch Wikipedia|Quality}}
* {{Slink|German Wikipedia|Reviews and research}}
* {{Slink|Spanish Wikipedia|Evaluation and criticism}}
}}

== Further reading ==
* <!-- Wikipedia U: Knowledge, Authority, and Liberal Education in the Digital Age -->{{cite Q|Q108733210}}?

== Notes ==
{{reflist|group=nb}}

== References ==
{{reflist|30em}}

== External links ==
{{wikiversity|Is Wikipedia a legitimate research source?}}
{{Scholia|topic}}
* [http://liswiki.org/wiki/Wikipedia Librarians' Claims and Opinions Regarding Wikipedia] at LISWiki.
* [http://wikipediocracy.com/2014/07/20/how-pranks-hoaxes-and-manipulation-undermine-the-reliability-of-wikipedia/ ''How pranks, hoaxes and manipulation undermine the reliability of Wikipedia''] {{Webarchive|url=https://web.archive.org/web/20140808220332/http://wikipediocracy.com/2014/07/20/how-pranks-hoaxes-and-manipulation-undermine-the-reliability-of-wikipedia/ |date=August 8, 2014 }}, a harsh essay by Andreas Kolbe.
* [https://www.sciencenews.org/blog/scicurious/wikipedia-science-reference-citations Wikipedia has become a science reference source even though scientists don't cite it]. ''[[Science News]].'' February 5, 2018.
* {{cite web | last=Moore | first=Ryan | title=When Did RFK Jr. Graduate from UVA Law? | website=[[Virginia Law Weekly]] | date=March 26, 2025 | url=https://www.lawweekly.org/col/2025/3/26/q2lhlbcl85im9jg094uenf51tj2j53 | access-date=March 28, 2025 | quote=Is the Encyclopedia Brittanica actually more accurate than Wikipedia? Is Wikipedia's reliance on the collective wisdom of the internet more reliable than the specialized knowledge of Encyclopedia Brittanica's army of paid fact checkers? How do we prove anything? What is the truth?}}

=== Wikipedia project pages ===
* {{self-reference link|Wikipedia:Press coverage|Press coverage}}
* {{self-reference link|Wikipedia:Replies to common objections|Replies to common objections}}
* {{self-reference link|Wikipedia:Researching with Wikipedia|Researching with Wikipedia}}
* {{self-reference link|Wikipedia:Statistics|Statistics}}
* {{self-reference link|Wikipedia:Wikipedia as a court source|Wikipedia as a court source}} (list of cited uses)
* {{self-reference link|Wikipedia:Wikipedia as an academic source|Wikipedia as an academic source}} (list of cited uses)
* {{self-reference link|Wikipedia:Academic studies of Wikipedia|Wikipedia in academic studies}} (list of studies)
* {{self-reference link|Wikipedia:WikiProject Wikipedia reliability|WikiProject Wikipedia reliability}}
* {{self-reference link|Wikipedia:America's Top Newspapers Use Wikipedia|America's Top Newspapers Use Wikipedia}}
* {{self-reference link|Wikipedia:Comparison to Stanford Encyclopedia of Philosophy|Comparison to ''Stanford Encyclopedia of Philosophy''}}
* [[Wikipedia:External peer review]]
** {{self-reference link|Wikipedia:External peer review/Nature December 2005|External peer review/''Nature'' December 2005}}

{{Wikipedia}}

[[Category:Wikipedia reliability| ]]
[[Category:Wikipedia]]
[[Category:English Wikipedia]]