Editing Wikipedia (section)

== Reception ==
{{see also|Academic studies about Wikipedia|Criticism of Wikipedia}}
{{update section|date=March 2018}}
Various Wikipedians have [[criticism of Wikipedia#Excessive regulation|criticized Wikipedia's large and growing regulation]], which includes more than fifty policies and nearly 150,000 words {{as of|2014|lc=y|post=.}}<ref name="bureaucracy">{{cite magazine |url=https://www.slate.com/articles/technology/future_tense/2014/06/wikipedia_s_bureaucracy_problem_and_how_to_fix_it.html |title = The Unbearable Bureaucracy of Wikipedia |last = Jemielniak |first = Dariusz |magazine = [[Slate (magazine)|Slate]] |date = June 22, 2014 |access-date = August 18, 2014}}</ref><ref name="Jemielniak">{{cite book |first=Dariusz |last=Jemielniak |author-link=Dariusz Jemielniak |title=Common Knowledge?: An Ethnography of Wikipedia |publisher=[[Stanford University Press]] |year=2014 |isbn=978-0804791205 |location=Stanford, CA}}</ref>

Critics have stated that Wikipedia exhibits [[systemic bias]]. In 2010, columnist and journalist [[Edwin Black]] described Wikipedia as being a mixture of "truth, half-truth, and some falsehoods".<ref name=EdwinBlack>{{cite news |first=Edwin |last=Black |author-link=Edwin Black |date=April 19, 2010 |work=[[History News Network]] |publisher=[[Columbian College of Arts and Sciences]] |title=Wikipedia—The Dumbing Down of World Knowledge |url=https://historynewsnetwork.org/article/125437 |url-status=live |archive-url=https://web.archive.org/web/20160909210831/https://historynewsnetwork.org/article/125437 |archive-date=September 9, 2016 |access-date=October 21, 2014}}</ref> Articles in ''[[The Chronicle of Higher Education]]'' and ''[[The Journal of Academic Librarianship]]'' have criticized Wikipedia's "Undue Weight" policy, concluding that the fact that Wikipedia explicitly is not designed to provide correct information about a subject, but rather focus on all the major viewpoints on the subject, give less attention to minor ones, and creates omissions that can lead to false beliefs based on incomplete information.<ref>{{cite news |last1=Messer-Krusse |first1=Timothy |title=The 'Undue Weight' of Truth on Wikipedia |url=https://www.chronicle.com/article/the-undue-weight-of-truth-on-wikipedia/ |work=[[The Chronicle of Higher Education]] |date=February 12, 2012 |url-access=subscription |url-status=live |archive-url=https://web.archive.org/web/20161218162359/https://chronicle.com/article/The-Undue-Weight-of-Truth-on/130704/ |archive-date=December 18, 2016 |access-date=March 27, 2014}}</ref><ref>{{cite journal |last1=Colón Aguirre |first1=Mónica |last2=Fleming-May |first2=Rachel A. |title="You Just Type in What You Are Looking For": Undergraduates' Use of Library Resources vs. Wikipedia |journal=[[The Journal of Academic Librarianship]] |date=November 2012 |volume=38 |issue=6 |page=392 |doi=10.1016/j.acalib.2012.09.013 |url=https://faculty.washington.edu/jwj/lis521/colon%20wikipedia.pdf |publisher=[[Elsevier]] |issn=0099-1333 |url-status=live |archive-url=https://web.archive.org/web/20160419031904/https://faculty.washington.edu/jwj/lis521/colon%20wikipedia.pdf |archive-date=April 19, 2016 |access-date=March 27, 2014}}</ref><ref>{{cite news |title=Wikipedia experience sparks national debate |url=https://www.bgsu.edu/news/2012/02/wikipedia-experience-sparks-national-debate.html |access-date=March 27, 2014 |work=BGSU News |publisher=[[Bowling Green State University]] |date=February 27, 2012 |url-status=live |archive-url=https://web.archive.org/web/20160827120800/https://www.bgsu.edu/news/2012/02/wikipedia-experience-sparks-national-debate.html |archive-date=August 27, 2016}}</ref>

Journalists [[Oliver Kamm]] and [[Edwin Black]] alleged (in 2010 and 2011 respectively) that articles are dominated by the loudest and most persistent voices, usually by a group with an "ax to grind" on the topic.<ref name=EdwinBlack /><ref name=okw>{{cite news |last1=Kamm |first1=Oliver |author1-link=Oliver Kamm |title=Wisdom? More like dumbness of the crowds |url=https://www.timesonline.co.uk/tol/comment/columnists/guest_contributors/article2267665.ece |work=[[The Times]] |archive-url=https://web.archive.org/web/20110814104256/https://www.timesonline.co.uk/tol/comment/columnists/guest_contributors/article2267665.ece |archive-date=August 14, 2011 |date=August 16, 2007}}</ref> A 2008 article in ''[[Education Next]]'' Journal concluded that as a resource about controversial topics, Wikipedia is subject to manipulation and [[spin (propaganda)|spin]].<ref name=Petrilli>{{cite journal |last1=Petrilli |first1=Michael J. |title=Wikipedia or Wickedpedia? |journal=Education Next |date=Spring 2008 |volume=8 |issue=2 |url=https://www.educationnext.org/wikipedia-or-wickedpedia/ |access-date=October 22, 2014 |publisher=[[Hoover Institution]] |url-status=live |archive-url=https://web.archive.org/web/20161121024654/https://educationnext.org/wikipedia-or-wickedpedia/ |archive-date=November 21, 2016 |department=What Next}}</ref>

In 2020, Omer Benjakob and Stephen Harrison noted that "Media coverage of Wikipedia has radically shifted over the past two decades: once cast as an intellectual frivolity, it is now lauded as the 'last bastion of shared reality' online."<ref>{{Cite book|last1=Benjakob|first1=Omer|last2=Harrison|first2=Stephen|date=2020-10-13|chapter=From Anarchy to Wikiality, Glaring Bias to Good Cop: Press Coverage of Wikipedia's First Two Decades|chapter-url=https://direct.mit.edu/books/book/4956/chapter/1879815/From-Anarchy-to-Wikiality-Glaring-Bias-to-Good-Cop|title=Wikipedia @ 20: Stories of an Incomplete Revolution|publisher=[[MIT Press]]|language=en|doi=10.7551/mitpress/12366.003.0005|isbn=978-0262360593|doi-access=free}}</ref>

In 2022, [[John Stossel]] opined that Wikipedia, a site he financially supported at one time, appears to have gradually taken a significant turn in bias to the political left, specifically on political topics.<ref>{{Cite web | url=https://www.johnstossel.com/wikipedia-bias/ | title=Wikipedia Bias | date=April 27, 2022 }}</ref>

In 2006, the ''Wikipedia Watch'' criticism website listed dozens of examples of [[plagiarism]] in the English Wikipedia.<ref name="wwplagiarism" />

=== Accuracy of content ===
{{main|Reliability of Wikipedia}}
{{External media | width = 230px | align = right | audio1 = [https://www.cbc.ca/radio/ideas/the-great-book-of-knowledge-part-1-1.2497560 The Great Book of Knowledge, Part 1], ''Ideas with [[Paul Kennedy (host)|Paul Kennedy]]'', [[Canadian Broadcasting Corporation|CBC]], January 15, 2014}}
Articles for traditional encyclopedias such as ''[[Encyclopædia Britannica]]'' are written by experts, lending such encyclopedias a reputation for accuracy.<ref>{{cite news |url=https://archive.wired.com/culture/lifestyle/news/2005/12/69844 |title = Wikipedia, Britannica: A Toss-Up |magazine = Wired |date = December 15, 2005 |access-date = August 8, 2015 |agency = Associated Press}}</ref> However, a peer review in 2005 of forty-two scientific entries on both Wikipedia and ''Encyclopædia Britannica'' by the science journal ''Nature'' found few differences in accuracy, and concluded that "the average science entry in Wikipedia contained around four inaccuracies; ''Britannica'', about three."<ref name="GilesJ2005Internet" /> Joseph Reagle suggested that while the study reflects "a topical strength of Wikipedia contributors" in science articles, "Wikipedia may not have fared so well using a random sampling of articles or on humanities subjects."<ref name="Reagle, pp. 165–166">Reagle, pp. 165–166.</ref> Others raised similar critiques.<ref name="Orlowski2005">{{cite news|last1=Orlowski|first1=Andrew|date=December 16, 2005|title=Wikipedia science 31% more cronky than Britannica's Excellent for Klingon science, though|work=[[The Register]]|url=https://www.theregister.co.uk/2005/12/16/wikipedia_britannica_science_comparison/|access-date=February 25, 2019}}</ref> The findings by ''Nature'' were disputed by ''Encyclopædia Britannica'',<ref name="corporate.britannica.com" /><ref name="nature.com britannica response 1">{{cite web |url=https://www.nature.com/press_releases/Britannica_response.pdf |archive-url=https://web.archive.org/web/20060325124447/https://www.nature.com/press_releases/Britannica_response.pdf |archive-date=25 March 2006 |title = Encyclopaedia Britannica and Nature: a response |access-date = July 13, 2010}}</ref> and in response, ''Nature'' gave a rebuttal of the points raised by ''Britannica''.<ref name="nature.com">{{cite web |website = Nature |url=https://www.nature.com/nature/britannica/index.html |title = Nature's responses to Encyclopaedia Britannica |date = March 30, 2006 |access-date = February 25, 2018|archive-url=https://web.archive.org/web/20170515025717/https://www.nature.com/nature/britannica/index.html|archive-date=May 15, 2017}}</ref> In addition to the point-for-point disagreement between these two parties, others have examined the sample size and selection method used in the ''Nature'' effort, and suggested a "flawed study design" (in ''Nature''{{'}}s manual selection of articles, in part or in whole, for comparison), absence of statistical analysis (e.g., of reported [[confidence interval]]s), and a lack of study "statistical power" (i.e., owing to small [[sample size determination|sample size]], 42 or 4{{nbsp}}× 10<sup>1</sup> articles compared, vs >10<sup>5</sup> and >10<sup>6</sup> set sizes for ''Britannica'' and the English Wikipedia, respectively).<ref>See author acknowledged comments in response to the citation of the ''Nature'' study, at ''PLoS ONE'', 2014, "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}}, see {{cite web |url=https://www.plosone.org/annotation/listThread.action?root%3D80078 |title = Dynamics of Conflicts in Wikipedia |access-date = July 22, 2014 |url-status=dead |archive-url=https://web.archive.org/web/20160116210930/https://www.plosone.org/annotation/listThread.action?root=80078 |archive-date = January 16, 2016 |df = mdy-all}}, accessed July 21, 2014.</ref>

As a consequence of the open structure, Wikipedia "makes no guarantee of validity" of its content, since no one is ultimately responsible for any claims appearing in it.<ref name="WP general disclaimer 1">{{cite web |url=https://en.wikipedia.org/wiki/Wikipedia:General_disclaimer |title = Wikipedia:General disclaimer |publisher = English Wikipedia |access-date = April 22, 2008 |date = September 18, 2018}}</ref> Concerns have been raised by ''PC World'' in 2009 regarding the lack of [[accountability]] that results from users' anonymity,<ref name="WikipediaWatch" /> the insertion of false information,<ref name="pcworld WP blunders 1">{{cite web |last = Raphel |first = JR |url=https://www.pcworld.com/article/170874/the_15_biggest_wikipedia_blunders.html |title = The 15 Biggest Wikipedia Blunders |website = [[PC World]] |access-date = September 2, 2009 |date = August 26, 2009}}</ref> [[vandalism on Wikipedia|vandalism]], and similar problems.

Economist [[Tyler Cowen]] wrote: "If I had to guess whether Wikipedia or the median refereed journal article on economics was more likely to be true after a not so long think I would opt for Wikipedia." He comments that some traditional sources of non-fiction suffer from systemic biases, and novel results, in his opinion, are over-reported in journal articles as well as relevant information being omitted from news reports. However, he also cautions that errors are frequently found on Internet sites and that academics and experts must be vigilant in correcting them.<ref name="tnr experts vigilant in correcting WP 1">{{cite magazine |url=https://www.tnr.com/story.html?id=82eb5d70-13bd-4086-9ec0-cb0e9e8411b3 |archive-url=https://web.archive.org/web/20080318103017/https://www.tnr.com/story.html?id=82eb5d70-13bd-4086-9ec0-cb0e9e8411b3 |archive-date = March 18, 2008 |title = Cooked Books |first = Tyler |last = Cowen |magazine = The New Republic |date = March 14, 2008 |access-date = December 26, 2008}}</ref> [[Amy Bruckman]] has argued that, due to the number of reviewers, "the content of a popular Wikipedia page is actually the most reliable form of information ever created".<ref name="PC 2021">{{cite news |last1=Stuart |first1=S.C. |title=Wikipedia: The Most Reliable Source on the Internet? |url=https://www.pcmag.com/news/wikipedia-the-most-reliable-source-on-the-internet |access-date=27 June 2021 |work=[[PCMag]] |date=3 June 2021 |language=en}}</ref>

Critics argue that Wikipedia's open nature and a lack of proper sources for most of the information makes it unreliable.<ref name="TNY reliability issues 1">{{cite news |first = Stacy |last = Schiff |date = July 31, 2006 |title = Know It All |magazine = [[The New Yorker]] |author-link = Stacy Schiff}}</ref> Some commentators suggest that Wikipedia may be reliable, but that the reliability of any given article is not clear.<ref name="AcademiaAndWikipedia" /> Editors of traditional [[reference work]]s such as the ''Encyclopædia Britannica'' have questioned the project's [[utility]] and status as an encyclopedia.<ref name="McHenry_2004" /> Wikipedia co-founder [[Jimmy Wales]] has claimed that Wikipedia has largely avoided the problem of "fake news" because the Wikipedia community regularly debates the quality of sources in articles.<ref>{{cite news|url=https://www.npr.org/2018/04/27/606393983/wikipedia-founder-says-internet-users-are-adrift-in-the-fake-news-era|title=Wikipedia Founder Says Internet Users Are Adrift In The 'Fake News' Era|work=NPR.org|access-date=May 1, 2018|archive-url=https://web.archive.org/web/20180625213220/https://www.npr.org/2018/04/27/606393983/wikipedia-founder-says-internet-users-are-adrift-in-the-fake-news-era|archive-date=June 25, 2018|url-status=live}}</ref>

{{External media | width = 210px | align = right | video1 = [https://www.dw.de/inside-wikipedia-attack-of-the-pr-industry/av-17745881 Inside Wikipedia&nbsp;– Attack of the PR Industry], [[Deutsche Welle]], 7:13 mins<ref name="dw">{{cite web |title = Inside Wikipedia&nbsp;– Attack of the PR Industry |publisher = [[Deutsche Welle]] |date = June 30, 2014 |url = https://www.dw.de/inside-wikipedia-attack-of-the-pr-industry/av-17745881 |access-date = July 2, 2014 |archive-date = July 1, 2014 |archive-url = https://web.archive.org/web/20140701152647/http://www.dw.de/inside-wikipedia-attack-of-the-pr-industry/av-17745881 |url-status = dead }}</ref>}}
Wikipedia's open structure inherently makes it an easy target for [[Internet troll]]s, [[spamming|spammer]]s, and various forms of paid advocacy seen as counterproductive to the maintenance of a neutral and verifiable online encyclopedia.<ref name="Torsten_Kleinz" /><ref name="citizendium WP trolling issues 1">{{cite web |title = Toward a New Compendium of Knowledge (longer version) |url=https://www.citizendium.org/essay.html |website = Citizendium |access-date = October 10, 2006 |archive-url=https://web.archive.org/web/20061011230402/https://www.citizendium.org/essay.html |archive-date = October 11, 2006}}</ref>
In response to [[conflict-of-interest editing on Wikipedia|paid advocacy editing]] and undisclosed editing issues, Wikipedia was reported in an article in ''The Wall Street Journal'', to have strengthened its rules and laws against undisclosed editing.<ref name="ReferenceA">{{cite news |title = Wikipedia Strengthens Rules Against Undisclosed Editing |url=https://blogs.wsj.com/digits/2014/06/16/wikipedia-strengthens-rules-against-undisclosed-editing/ |author = Elder, Jeff |newspaper = [[The Wall Street Journal]] |date = June 16, 2014}}</ref> The article stated that: "Beginning Monday [from the date of the article, June 16, 2014], changes in Wikipedia's terms of use will require anyone paid to edit articles to disclose that arrangement. [[Katherine Maher]], the nonprofit Wikimedia Foundation's chief communications officer, said the changes address a sentiment among volunteer editors that, 'we're not an advertising service; we're an encyclopedia.{{'"}}<ref name="ReferenceA" /><ref name="DeathByWikipedia" /><ref name="cnet politicians and WP 1">{{cite web |url = https://news.cnet.com/8301-10784_3-6032713-7.html |title = Politicians notice Wikipedia |website = CNET |author = Kane, Margaret |date = January 30, 2006 |access-date = January 28, 2007 |archive-date = July 30, 2009 |archive-url = https://web.archive.org/web/20090730044856/http://news.cnet.com/8301-10784_3-6032713-7.html |url-status = dead }}</ref><ref name="msnbc MS cash for WP edits 1">{{cite web |url=https://www.nbcnews.com/id/16775981 |title = Microsoft offers cash for Wikipedia edit |work = NBC News |author = Bergstein, Brian |author-link = Brian Bergstein |date = January 23, 2007 |access-date = February 1, 2007}}</ref><ref name="Seeing Corporate Fingerprints" /> These issues, among others, had been parodied since the first decade of Wikipedia, notably by [[Stephen Colbert]] on ''[[The Colbert Report]]''.<ref name="wikiality" />

A Harvard law textbook, ''Legal Research in a Nutshell'' (2011), cites Wikipedia as a "general source" that "can be a real boon" in "coming up to speed in the law governing a situation" and, "while not authoritative, can provide basic facts as well as leads to more in-depth resources".<ref name="Nutshell in-depth resources">{{cite book|title=Legal Research in a Nutshell|last=Cohen|first=Morris|author2=Olson, Kent|publisher=Thomson Reuters|year=2010|isbn=978-0314264084|edition=10th|location=St. Paul, MN|pages=[https://archive.org/details/legalre_coh_2010_00_0532/page/32 32–34]|url=https://archive.org/details/legalre_coh_2010_00_0532}}</ref>

=== Discouragement in education ===
{{update section|date=December 2020}}
Most university [[lecturer]]s discourage students from citing any encyclopedia in [[academia|academic work]], preferring [[primary source]]s;<ref name="WideWorldOfWikipedia" /> some specifically prohibit Wikipedia citations.<ref name="insidehighered against WP 1">{{cite journal |last1 = Waters |first1 = N.L. |title = Why you can't cite Wikipedia in my class |doi = 10.1145/1284621.1284635 |journal = Communications of the ACM |volume = 50 |issue = 9 |page = 15 |year = 2007 |citeseerx = 10.1.1.380.4996|s2cid = 11757060 }}</ref><ref name="insidehighered wiki no cite">{{cite web |first = Scott |last = Jaschik |title = A Stand Against Wikipedia |url=https://www.insidehighered.com/news/2007/01/26/wiki |website = Inside Higher Ed |date = January 26, 2007 |access-date = January 27, 2007}}</ref> Wales stresses that encyclopedias of any type are not usually appropriate to use as citable sources, and should not be relied upon as authoritative.<ref name="AWorkInProgress" /> Wales once (2006 or earlier) said he receives about ten [[email]]s weekly from students saying they got failing grades on papers because they cited Wikipedia; he told the students they got what they deserved. "For God's sake, you're in college; don't cite the encyclopedia," he said.<ref name="Jimmy Wales don't cite WP 1">"Jimmy Wales", ''Biography Resource Center Online''. (Gale, 2006.)</ref>

In February 2007, an article in ''[[The Harvard Crimson]]'' newspaper reported that a few of the professors at [[Harvard University]] were including Wikipedia articles in their [[syllabus|syllabi]], although without realizing the articles might change.<ref name="thecrimson wiki debate">{{cite news |last1=Child |first1=Maxwell L. |title=Professors Split on Wiki Debate |url=https://www.thecrimson.com/article.aspx?ref=517305 |work=[[The Harvard Crimson]] |date=February 26, 2007 |archive-url=https://web.archive.org/web/20081220125910/https://www.thecrimson.com/article.aspx?ref=517305 |archive-date=December 20, 2008 |location=Cambridge, MA}}</ref> In June 2007, former president of the [[American Library Association]] [[Michael Gorman (librarian)|Michael Gorman]] condemned Wikipedia, along with [[Google]], stating that academics who endorse the use of Wikipedia are "the intellectual equivalent of a dietitian who recommends a steady diet of Big Macs with everything".<ref name="stothart" />

In contrast, academic writing{{clarify|date=December 2020}} in Wikipedia has evolved in recent years and has been found to increase student interest, personal connection to the product, creativity in material processing, and international collaboration in the learning process.<ref>{{cite web|url=https://www.quest-cdecjournal.it/focus.php?id=403|title=Wikishtetl: Commemorating Jewish Communities that Perished in the Holocaust through the Wikipedia Platform :: Quest CDEC journal|website=www.quest-cdecjournal.it|date=July 31, 2018|access-date=January 15, 2020}}</ref>

==== Medical information ====
{{see also|Health information on Wikipedia}}
On March 5, 2014, Julie Beck writing for ''The Atlantic'' magazine in an article titled "Doctors' #1 Source for Healthcare Information: Wikipedia", stated that "Fifty percent of physicians look up conditions on the (Wikipedia) site, and some are editing articles themselves to improve the quality of available information."<ref name="Julie Beck 2014">Julie Beck. "Doctors' #1 Source for Healthcare Information: Wikipedia". ''The Atlantic'', March 5, 2014.</ref> Beck continued to detail in this article new programs of [[Amin Azzam]] at the [[University of San Francisco]] to offer medical school courses to medical students for learning to edit and improve [[health information on Wikipedia|Wikipedia articles on health-related issues]], as well as internal quality control programs within Wikipedia organized by [[James Heilman]] to improve a group of 200 health-related articles of central medical importance up to Wikipedia's highest standard of articles using its Featured Article and Good Article peer-review evaluation process.<ref name="Julie Beck 2014" /> In a May 7, 2014, follow-up article in ''The Atlantic'' titled "Can Wikipedia Ever Be a Definitive Medical Text?", Julie Beck quotes WikiProject Medicine's James Heilman as stating: "Just because a reference is peer-reviewed doesn't mean it's a high-quality reference."<ref name="theatlantic.com">{{cite magazine |last = Beck |first = Julie |url=https://www.theatlantic.com/health/archive/2014/05/can-wikipedia-ever-be-a-definitive-medical-text/361822/ |title = Can Wikipedia Ever Be a Definitive Medical Text? |magazine = The Atlantic |date = May 7, 2014 |access-date = June 14, 2014}}</ref> Beck added that: "Wikipedia has its own peer review process before articles can be classified as 'good' or 'featured'. Heilman, who has participated in that process before, says 'less than one percent' of Wikipedia's medical articles have passed."<ref name="theatlantic.com" />

=== Coverage of topics and systemic bias ===
{{see also|Notability in the English Wikipedia|Criticism of Wikipedia#Systemic bias in coverage}}
{{update|[[:d:Wikidata:Statistics/Wikipedia]]|date=March 2017}}
Wikipedia seeks to create a summary of all human knowledge in the form of an online encyclopedia, with each topic covered encyclopedically in one article. Since it has [[byte#Multiple-byte units|terabyte]]s of disk space, it can have far more topics than can be covered by any printed encyclopedia.<ref name="WP advantages over trad media 1">{{srlink|Wikipedia:PAPER}}</ref> The exact degree and manner of coverage on Wikipedia is under constant review by its editors, and disagreements are not uncommon (see [[deletionism and inclusionism in Wikipedia|deletionism and inclusionism]]).<ref name="Economist disagreements not uncommon">{{cite news |title = The battle for Wikipedia's soul |url=https://www.economist.com/printedition/displaystory.cfm?story_id=10789354 |newspaper = The Economist |date = March 6, 2008 |access-date = March 7, 2008 |issn=0013-0613}}</ref><ref name="telegraph WP torn apart 1">{{cite news |title = Wikipedia: an online encyclopedia torn apart |first = Ian |last = Douglas |work = The Daily Telegraph |location = London |date = November 10, 2007 |url=https://www.telegraph.co.uk/technology/3354752/Wikipedia-an-online-encyclopedia-torn-apart.html |archive-url=https://ghostarchive.org/archive/20220110/https://www.telegraph.co.uk/technology/3354752/Wikipedia-an-online-encyclopedia-torn-apart.html |archive-date=2022-01-10 |url-access=subscription |url-status=live |access-date = November 23, 2010}}{{cbignore}}</ref> Wikipedia contains materials that some people may find objectionable, offensive, or pornographic. The "Wikipedia is not censored" policy has sometimes proved controversial: in 2008, Wikipedia rejected an online petition against the inclusion of [[online petition on Wikipedia Muhammad article|images of Muhammad]] in the [[English Wikipedia|English edition]] of its [[Muhammad]] article, citing this policy. The presence of politically, religiously, and pornographically sensitive materials in Wikipedia has led to the [[censorship of Wikipedia]] by national authorities in China<ref name="Taylor" /> and Pakistan,<ref name="washington post state censorship 1">{{cite news |url=https://www.washingtonpost.com/wp-dyn/content/article/2010/05/20/AR2010052005073.html |title = Pakistan blocks YouTube a day after shutdown of Facebook over Muhammad issue |first = Karin |last = Bruilliard |newspaper = The Washington Post |date = May 21, 2010 |access-date = October 24, 2011}}</ref> amongst other countries.

[[File:Wikipedia content by subject.png|thumb|upright=2.27|Pie chart of Wikipedia content by subject {{as of|2008|1|lc=y}}<ref name=Kittur2009 />]]
A 2008 study conducted by researchers at Carnegie Mellon University and Palo Alto Research Center gave a distribution of topics as well as growth (from July 2006 to January 2008) in each field:<ref name="Kittur2009" />
* Culture and Arts: 30% (210%)
* Biographies and persons: 15% (97%)
* Geography and places: 14% (52%)
* Society and social sciences: 12% (83%)
* History and events: 11% (143%)
* Natural and Physical Sciences: 9% (213%)
* Technology and Applied Science: 4% (−6%)
* Religions and belief systems: 2% (38%)
* Health: 2% (42%)
* Mathematics and logic: 1% (146%)
* Thought and Philosophy: 1% (160%)

These numbers refer only to the number of articles: it is possible for one topic to contain a large number of short articles and another to contain a small number of large ones. Through its "Wikipedia Loves Libraries" program, Wikipedia has partnered with major public libraries such as the [[New York Public Library for the Performing Arts]] to expand its coverage of underrepresented subjects and articles.<ref name="NYT subjects and articles">{{cite news |url=https://www.nytimes.com/2011/10/21/theater/editing-wikipedia-at-the-new-york-public-library-for-the-performing-arts.html |title = Wikipedia's Deep Dive Into a Library Collection |last = Petrusich |first = Amanda |work = The New York Times |date = October 20, 2011 |access-date = October 28, 2011}}</ref>

A 2011 study conducted by researchers at the [[University of Minnesota]] indicated that male and female editors focus on different coverage topics. There was a greater concentration of females in the "people and arts" category, while males focus more on "geography and science".<ref>{{cite journal |last1 = Lam |first1 = Shyong (Tony) K.|first2 = Anuradha |last2 = Uduwage |first3 = Zhenhua |last3 = Dong |first4 = Shilad |last4 = Sen |first5 = David R. |last5 = Musicant |first6 = Loren |last6 = Terveen |first7 = John |last7 = Riedl |title = WP: Clubhouse? An Exploration of Wikipedia's Gender Imbalance |journal = WikiSym 2011 |date = October 3–5, 2011 |page = 4 |url=https://files.grouplens.org/papers/wp-gender-wikisym2011.pdf}}</ref>

==== Coverage of topics and selection bias ====
Research conducted by Mark Graham of the [[Oxford Internet Institute]] in 2009 indicated that the geographic distribution of article topics is highly uneven. Africa is the most underrepresented.<ref>{{cite web |last1=Graham |first1=Mark |title=Mapping the Geographies of Wikipedia Content |url=https://zerogeography.net/post/144973716228/mapping-the-geographies-of-wikipedia-content |website=Zerogeography |archive-url=https://web.archive.org/web/20161002051150/https://zerogeography.net/post/144973716228/mapping-the-geographies-of-wikipedia-content |archive-date=October 2, 2016}}</ref> Across 30 language editions of Wikipedia, historical articles and sections are generally Eurocentric and focused on recent events.<ref>{{cite book |last = Strohmaier |first = Markus |date = March 6, 2017 |title = Multilingual historical narratives on Wikipedia |chapter = KAT50 Society, Culture |doi = 10.7802/1411 |quote = Wikipedia narratives about national histories (i) are skewed towards more recent events (recency bias) and (ii) are distributed unevenly across the continents with significant focus on the history of European countries (Eurocentric bias). |publisher = GESIS Data Archive}}</ref>

An editorial in ''[[The Guardian]]'' in 2014 claimed that more effort went into providing references for [[list of pornographic performers by decade|a list of female porn actors]] than a [[list of women writers]].<ref name=GuardianAugust2014>{{cite news |title=The Guardian view on Wikipedia: evolving truth |url=https://www.theguardian.com/commentisfree/2014/aug/07/guardian-view-wikipedia-evolving-truth |work=[[The Guardian]] |date=August 7, 2014 |archive-url=https://web.archive.org/web/20161112212758/https://www.theguardian.com/commentisfree/2014/aug/07/guardian-view-wikipedia-evolving-truth |archive-date=November 12, 2016 |url-status=live}}</ref> Data has also shown that Africa-related material often faces omission; a knowledge gap that a July 2018 Wikimedia conference in [[Cape Town]] sought to address.<ref name="memeb"/>

==== Systemic biases ====
When multiple editors contribute to one topic or set of topics, [[systemic bias]] may arise, due to the demographic backgrounds of the editors. In 2011, Wales claimed that the unevenness of coverage is a reflection of the demography of the editors, citing for example "biographies of famous women through history and issues surrounding early childcare".<ref name="wiki-women">{{cite news |title = Wikipedia seeks women to balance its 'geeky' editors |first = Kevin |last = Rawlinson |newspaper = The Independent |url=https://www.independent.co.uk/life-style/gadgets-and-tech/news/wikipedia-seeks-women-to-balance-its-geeky-editors-2333605.html |date = August 8, 2011 |access-date = April 5, 2012}}</ref> The October 22, 2013, essay by Tom Simonite in MIT's ''Technology Review'' titled "The Decline of Wikipedia" discussed the effect of systemic bias and [[criticism of Wikipedia#Excessive regulation|policy creep]] on the [[#English Wikipedia editor numbers|downward trend in the number of editors]].<ref name="Simonite-2013" />

Systemic bias on Wikipedia may follow that of culture generally,{{vague|date=August 2019}} for example favoring certain nationalities, ethnicities or majority religions.<ref name="Quilter">{{cite web |url=https://works.bepress.com/cgi/viewcontent.cgi?article=1035&context=laura_quilter |title = Systemic Bias in Wikipedia: What It Looks Like, and How to Deal with It |author = Quilter, Laura |publisher = University of Massachusetts–Amherst |date = October 24, 2012 |access-date = November 26, 2012}}</ref> It may more specifically follow the biases of [[Internet culture]], inclining to be young, male, English-speaking, educated, technologically aware, and wealthy enough to spare time for editing. Biases, intrinsically, may include an overemphasis on topics such as pop culture, technology, and current events.<ref name="Quilter" />{{better source needed|date=June 2022}}<!--cited source is a PowerPoint Presentation, with no evidence of having been peer reviewed or accepted at a conference-->

[[Taha Yasseri]] of the [[University of Oxford]], in 2013, studied the statistical trends of systemic bias at Wikipedia introduced by editing conflicts and their resolution.<ref>{{cite magazine |date=July 17, 2013 |title=Edit Wars Reveal The 10 Most Controversial Topics on Wikipedia |url=https://www.technologyreview.com/2013/07/17/177320/edit-wars-reveal-the-10-most-controversial-topics-on-wikipedia/ |magazine=[[MIT Technology Review]] |location=Cambridge, MA |publisher=[[Massachusetts Institute of Technology]]}}</ref><ref name="autogenerated3">{{cite book |ssrn = 2269392 |editor1=Fichman, P. |editor2=Hara, N. |publisher=Scarecrow Press |year=2014 |arxiv = 1305.5566 |last1 = Yasseri |first1 = Taha |last2 = Spoerri |first2 = Anselm |last3 = Graham |first3 = Mark |last4 = Kertész |first4 = János|title= The Most Controversial Topics in Wikipedia: A Multilingual and Geographical Analysis |doi= 10.2139/SSRN.2269392 |s2cid = 12133330 |author1-link=Taha Yasseri |author4-link=János Kertész}}</ref> His research examined the [[counterproductive work behavior]] of edit warring. Yasseri contended that simple reverts or "undo" operations were not the most significant measure of counterproductive behavior at Wikipedia and relied instead on the [[statistical measurement]] of detecting "reverting/reverted pairs" or "mutually reverting edit pairs". Such a "mutually reverting edit pair" is defined where one editor reverts the edit of another editor who then, in sequence, returns to revert the first editor in the "mutually reverting edit pairs". The results were tabulated for several language versions of Wikipedia. The English Wikipedia's three largest conflict rates belonged to the articles [[George W. Bush]], [[anarchism]], and [[Muhammad]].<ref name="autogenerated3" /> By comparison, for the German Wikipedia, the three largest conflict rates at the time of the [[Oxford]] study were for the articles covering [[Croatia]], [[Scientology]], and [[9/11 conspiracy theories]].<ref name="autogenerated3"/>

Researchers from [[Washington University]] developed a statistical model to measure systematic bias in the behavior of Wikipedia's users regarding controversial topics. The authors focused on behavioral changes of the encyclopedia's administrators after assuming the post, writing that systematic bias occurred after the fact.<ref>
{{cite conference |url=https://dl.acm.org/citation.cfm?id=2505566 |title = Manipulation among the arbiters of collective intelligence: How Wikipedia administrators mold public opinion |last1 = Das |first1 = Sanmay |last2 = Allen |first2 = Lavoie |last3 = Malik |first3 = Magdon-Ismail |date = November 1, 2013 |publisher = ACM |book-title = CIKM '13 Proceedings of the 22nd ACM international conference on Information & Knowledge Management |pages = 1097–1106 |location = San Francisco |doi = 10.1145/2505515.2505566 |isbn = 978-1450322638}}
</ref><ref>{{cite journal |last1 = Das |first1 = Sanmay |last2 = Allen |first2 = Lavoie |last3 = Malik |first3 = Magdon-Ismail |title = Manipulation among the arbiters of collective intelligence: How Wikipedia administrators mold public opinion |journal = ACM Transactions on the Web |volume = 10 |issue = 4 |pages = 24 |date = December 24, 2016 |doi = 10.1145/3001937|s2cid = 12585047 }}
</ref>

=== Explicit content ===
{{see also|Internet Watch Foundation and Wikipedia|Reporting of child pornography images on Wikimedia Commons}}
{{for|the government censorship of Wikipedia|Censorship of Wikipedia}}
{{self reference|For Wikipedia's policy concerning censorship, see [[Wikipedia:Wikipedia is not censored]]}}
Wikipedia has been criticized for allowing information about graphic content. Articles depicting what some critics have called objectionable content (such as [[feces]], [[cadaver]], [[human penis]], [[vulva]], and [[nudity]]) contain graphic pictures and detailed information easily available to anyone with access to the internet, including children.

The site also includes [[sexual content]] such as images and videos of [[masturbation]] and [[ejaculation]], illustrations of [[zoophilia]], and photos from [[hardcore pornography|hardcore pornographic]] films in its articles. It also has non-sexual [[child nudity|photographs of nude children]].

The Wikipedia article about ''[[Virgin Killer]]—''a 1976 album from the [[music of Germany|German]] [[rock music|rock]] [[rock band|band]] [[Scorpions (band)|Scorpions]]—features a picture of the album's original cover, which depicts a naked [[preadolescence#Prepubescence, puberty, and age range|prepubescent]] girl. The original release cover caused controversy and was replaced in some countries. In December 2008, access to the Wikipedia article ''Virgin Killer'' was blocked for four days by most [[Internet service provider]]s in the United Kingdom after the [[Internet Watch Foundation]] (IWF) decided the album cover was a potentially illegal indecent image and added the article's URL to a "blacklist" it supplies to British internet service providers.<ref name="Register ISP censorship">{{cite news |title = Brit ISPs censor Wikipedia over 'child porn' album cover |first = Cade |last = Metz |work = [[The Register]] |date = December 7, 2008 |url=https://www.theregister.co.uk/2008/12/07/brit_isps_censor_wikipedia |access-date = May 10, 2009}}</ref>

In April 2010, Sanger wrote a letter to the Federal Bureau of Investigation, outlining his concerns that two categories of images on [[Wikimedia Commons]] contained child pornography, and were in violation of [[United States obscenity law|US federal obscenity law]].<ref>{{cite news |url=https://www.smh.com.au/technology/technology-news/wikipedia-rejects-child-porn-accusation-20100428-tsvh |title = Wikipedia rejects child porn accusation |date = April 29, 2010 |work = The Sydney Morning Herald |access-date = May 14, 2017 |archive-url=https://web.archive.org/web/20170902180523/https://www.smh.com.au/technology/technology-news/wikipedia-rejects-child-porn-accusation-20100428-tsvh |archive-date = September 2, 2017 |url-status=live |df = mdy-all}}</ref><ref name="Inquirer child abuse allegations">{{cite news |last = Farrell |first = Nick |title = Wikipedia denies child abuse allegations: Co-founder grassed the outfit to the FBI |newspaper = The Inquirer |date = April 29, 2010 |url=https://www.theinquirer.net/inquirer/news/1603521/wikipedia-denies-child-abuse-allegations |archive-url=https://web.archive.org/web/20100501174521/https://www.theinquirer.net/inquirer/news/1603521/wikipedia-denies-child-abuse-allegations |url-status = unfit |archive-date = May 1, 2010 |access-date = October 9, 2010}}</ref> Sanger later clarified that the images, which were related to [[pedophilia]] and one about [[lolicon]], were not of real children, but said that they constituted "obscene visual representations of the sexual abuse of children", under the [[child pornography laws in the United States#Section 1466A|PROTECT Act of 2003]].<ref name="The Register-April" /> That law bans photographic child pornography and cartoon images and drawings of children that are [[obscenity#United States obscenity law|obscene under American law]].<ref name="The Register-April" /> Sanger also expressed concerns about access to the images on Wikipedia in schools.<ref name="TET child porn accusations">{{cite news |title = Wikipedia blasts co-founder's accusations of child porn on website |date = April 29, 2010 |work = The Economic Times |location = India |url=https://economictimes.indiatimes.com/infotech/internet/Wikipedia-blasts-co-founders-accusations-of-child-porn-on-website/articleshow/5871943.cms |access-date = April 29, 2010}}</ref> [[Wikimedia Foundation]] spokesman Jay Walsh strongly rejected Sanger's accusation,<ref name="AFP" /> saying that Wikipedia did not have "material we would deem to be illegal. If we did, we would remove it."<ref name="AFP" /> Following the complaint by Sanger, Wales deleted sexual images without consulting the community. After some editors who volunteer to maintain the site argued that the decision to delete had been made hastily, Wales voluntarily gave up some of the powers he had held up to that time as part of his co-founder status. He wrote in a message to the Wikimedia Foundation mailing-list that this action was "in the interest of encouraging this discussion to be about real philosophical/content issues, rather than be about me and how quickly I acted".<ref name="BBC News Wales cedes rights">{{cite news |url=https://news.bbc.co.uk/2/hi/technology/10104946.stm |title = Wikimedia pornography row deepens as Wales cedes rights |work = BBC News |date = May 10, 2010 |access-date = May 19, 2010}}</ref> Critics, including [[Wikipediocracy]], noticed that many of the pornographic images deleted from Wikipedia since 2010 have reappeared.<ref name="XBIZ">{{cite news |url = https://newswire.xbiz.com/view.php?id=169017 |work = XBIZ.com |date = September 17, 2013 |first = Lila |last = Gray |title = Wikipedia Gives Porn a Break |access-date = November 10, 2013 |archive-date = June 16, 2017 |archive-url = https://web.archive.org/web/20170616073432/http://newswire.xbiz.com/view.php?id=169017 |url-status = dead }}</ref>

=== Privacy ===
One [[privacy]] concern in the case of Wikipedia is the right of a private citizen to remain a "private citizen" rather than a "[[public figure]]" in the eyes of the law.<ref>{{cite book |last1=McStay |first1=Andrew |title=Privacy and Philosophy: New Media and Affective Protocol |date=2014 |publisher=[[Peter Lang (publisher)|Peter Lang]] |isbn=978-1454191636 |doi=10.3726/978-1-4539-1336-9 |series=Digital Formation |volume=86}}</ref><ref group=note>See [https://web.archive.org/web/20101130081035/https://texaspress.com/index.php/publications/law-media/731-law-a-the-media-in-texas--libel-cases "Libel"] by David McHam for the legal distinction.</ref> It is a battle between the right to be anonymous in [[cyberspace]] and the right to be anonymous in [[real life]] ("[[meatspace]]"). A particular problem occurs in the case of a relatively unimportant individual and for whom there exists a Wikipedia page against her or his wishes.

In January 2006, a German court ordered the [[German Wikipedia]] shut down within Germany because it stated the full name of [[Tron (hacker)|Boris Floricic]], aka "Tron", a deceased hacker. On February 9, 2006, the injunction against Wikimedia Deutschland was overturned, with the court rejecting the notion that Tron's [[right to privacy]] or that of his parents was being violated.<ref name="heise Tron public issue 1">{{cite news |last1=Kleinz |first1=Torsten |title=Gericht weist einstweilige Verfügung gegen Wikimedia Deutschland ab [Update] |url=https://www.heise.de/newsticker/meldung/Gericht-weist-einstweilige-Verfuegung-gegen-Wikimedia-Deutschland-ab-Update-173587.html |work=Heise Online |publisher=[[Heinz Heise]] |date=September 2, 2006 |language=de |trans-title=Court rejects preliminary injunction against Wikimedia Germany [Update] |url-status=live |archive-url=https://web.archive.org/web/20120913054949/https://www.heise.de/newsticker/meldung/Gericht-weist-einstweilige-Verfuegung-gegen-Wikimedia-Deutschland-ab-Update-173587.html |archive-date=September 13, 2012}}</ref>

Wikipedia has a "{{visible anchor|Volunteer Response Team}}" that uses Znuny, a [[free and open-source software]] fork of [[OTRS]]<ref>[[meta:Volunteer Response Team|Meta-wiki on Volunteer Response Team]]</ref> to handle queries without having to reveal the identities of the involved parties. This is used, for example, in confirming the permission for using individual images and other media in the project.<ref>{{cite web |title = IT Service Management Software |url=https://www.otrs.com/en/ |publisher = OTRS.com |access-date = June 9, 2012 |url-status=dead |archive-url=https://web.archive.org/web/20131030215341/https://www.otrs.com/en/ |archive-date = October 30, 2013 |df = mdy-all}}</ref>

=== Sexism ===
{{main|Gender bias on Wikipedia}}
Wikipedia was described in 2015 as harboring a battleground culture of [[sexism]] and [[harassment]].<ref name="Paling">{{cite web |url=https://www.theatlantic.com/technology/archive/2015/10/how-wikipedia-is-hostile-to-women/411619/ |title = Wikipedia's Hostility to Women |last = Paling |first = Emma |date = October 21, 2015 |website = The Atlantic |access-date = October 24, 2015}}</ref><ref>{{cite journal |last1 = Auerbach |first1 = David |title = Encyclopedia Frown |url=https://www.slate.com/articles/technology/bitwise/2014/12/wikipedia_editing_disputes_the_crowdsourced_encyclopedia_has_become_a_rancorous.html |journal = Slate |access-date = October 24, 2015 |date = December 11, 2014}}</ref>

The perceived toxic attitudes and tolerance of violent and abusive language were reasons put forth in 2013 for the gender gap in Wikipedia editorship.<ref name="CSM-misogyny">{{cite journal |url=https://www.csmonitor.com/World/Security-Watch/Backchannels/2013/0801/In-UK-rising-chorus-of-outrage-over-online-misogyny |title = In UK, rising chorus of outrage over online misogyny |journal = Christian Science Monitor |date = August 2013}}</ref>

[[Edit-a-thon]]s have been held to encourage female editors and increase the coverage of women's topics.<ref>{{cite news|last1=Kueppers|first1=Courtney|last2=Journal-Constitution|first2=The Atlanta|title=High Museum to host virtual Wikipedia edit-a-thon to boost entries about women|url=https://www.ajc.com/lifestyles/high-museum-host-virtual-wikipedia-edit-thon-boost-entries-about-women/TxxMEMGWHqFfaNMpV8y9DN/|access-date=October 24, 2020|newspaper=The Atlanta Journal-Constitution|language=en}}</ref>

A comprehensive 2008 survey, published in 2016, found significant gender differences in: confidence in expertise, discomfort with editing, and response to critical feedback. "Women reported less confidence in their expertise, expressed greater discomfort with editing (which typically involves conflict), and reported more negative responses to critical feedback compared to men."<ref>{{cite journal |author1=Julia B. Bear & Benjamin Collier |title=Where are the Women in Wikipedia ? – Understanding the Different Psychological Experiences of Men and Women in Wikipedia |journal=Sex Roles |url=https://link.springer.com/article/10.1007/s11199-015-0573-y |publisher=[[Springer Science+Business Media|Springer Science]] |date=4 January 2016|volume=74 |issue=5–6 |pages=254–265 |doi=10.1007/s11199-015-0573-y |s2cid=146452625 }}</ref>