Quality control is essential to Wikipedia. To maintain articles of acceptable quality, it is necessary to improve the quality of existing material, and remove material of irreparably poor quality.
This article discusses aspects of quality control at Wikipedia which are used in developing and guiding policies and procedures at Wikipedia directed at article development. An important distinction is made between the editing of the content of articles to maintain quality, and, the conduct of editors involved in the improvement and enhancement of articles written for Wikipedia. The very wiki-nature of Wikipedia enables instant and continuous quality control, by allowing all editors in good standing to participate in improving articles and the encyclopedia as a whole. If someone comes across an error while reading Wikipedia, they can immediately and directly change it – by clicking on the Edit tab at the top of the screen, and then by typing away in the edit window that appears. While there are a few bad apples who abuse this privilege by vandalizing or propagandizing, the vast majority of people who edit Wikipedia compose articles responsibly with the common good of humankind at heart – Wikipedia is a public resource intended to make knowledge freely available to everyone in the world, and most participants take this very seriously.
But mistakes sometimes occur. These, and the damage done by the bad apples mentioned above, need continuous attention. The three ways that Wikipedia maintains its quality control is as follows: (a) A great deal of Wikipedia's volunteers' effort is applied to quality control. Wikipedia has an elaborate disciplinary system for handling vandals and other troublemakers, and a dedicated force of system administrators to enforce the Wikipedia community's decisions and policies – admins even have the power to block a bad apple permanently. (b) Once material is added to Wikipedia, an army of volunteers organized under various departments check and recheck it to make sure it conforms to the high standards set forth in Wikipedia's policies and guidelines (which were established specifically with the creation of quality articles in mind). There are departments for everything from typos to factual errors. For a list, see Wikipedia:Maintenance. (c) And Wikipedia even has robots, automated users that monitor for errors and correct them automatically. For example, these days most vandalism is fixed by Wikipedia's robots, or our content editors, who are watching your every move. Be careful.
Article notability and inclusion
Monitoring articles and edits
Every edit is recorded!
- Main article: Help:Page history
Unlike paper encyclopedias which can only display a single version of an article, Wikipedia tracks every edit to every page. Each of these versions of the article, or revisions, is listed chronologically in the history tab, from which any and all previous revisions can be viewed. This is useful not only as a historical record by which we can analyze how articles change over time, but also to protect the integrity of the article. Because the most accurate and complete version of an article is always stored and readily accessible, bad edits (whether blatant vandalism or good faith errors) can be quickly reverted.
Live feeds – monitoring Wikipedia in real time
Recent changes patrol
- Main article: Wikipedia:Recent changes patrol
Special:RecentChanges lists, by default, the 50 most recent changes to all of Wikipedia. Members of Wikipedia:Recent changes patrol periodically scan this page for unusual activity, such as a large removal of content, an automatic edit summary, or even just edits made anonymously. The corresponding diffs can then be examined to determine whether or not the edits were constructive. The 50 most recent edits may have all occurred within the past one to two minutes. Thus, the recent changes patrol ensures that obvious vandalism is reverted within a few minutes of being added.
New pages patrol
- Main article: Wikipedia:New pages patrol
Counter vandalism vigilance
A watchlist is a MediaWiki feature that presents in a special list format all the recent edits (configurable to display edits up to 30 days old) for every article on the watchlist. On Wikipedia, there are two types of watchlist that are commonly used...
- Main article: Help:Watching pages
The MediaWiki software upon which Wikipedia is hosted includes a powerful feature called "My watchlist", accessible at the top of the screen by every user who has a Wikipedia account (which are free, by the way). Editors interested in working on or monitoring specific pages can watch those pages. The watchlist simultaneously displays the most recent revisions of every article that an editor is watching. This makes it very easy for an editor to quickly check over the articles they are working on to see if any dubious edits have occurred. Watchlisting ensures that editors with a good understanding of an article are aware of any incorrect information added, and that vandalism can be quickly reverted. Using this tool, experienced editors can effectively watch as many as 8,000 pages each.
Using changes to create specialized watchlists
- Main article: Wikipedia:Related changes
Reporting problems with pages and edits
- Main article: Wikipedia:Template messages
- Note: to deal with or report problems with a particular user, see Wikipedia:Dispute resolution.
Editorial oversight and control
- Main article: Wikipedia:Editorial oversight and control
Comparison to other encyclopedias
In general, Wikipedia responds rapidly to notable recent events, adding or updating information quickly. By contrast, many other encyclopedias cannot author detailed content about recent topics as promptly. However, questionable edits are sometimes made to articles, and it may take hours or days before they are removed or corrected. An editorial approval process known as "pending changes" has been applied in some cases, as a gatekeeping mechanism to prevent improper additions to articles. The German Wikipedia has used that process to screen pending-change requests for years, and some trusted editors are allowed to approve and release their own proposed updates to articles.
For technical subjects, unusual claims in articles typically take longer to verify or correct, depending on the time needed by experts in the subject to review the subject matter. In his book The Last Lecture, Computer science professor Randy Pausch (1960–2008) recounted his experience writing an article for the World Book Encyclopedia:
- "No editor ever questioned what I wrote, but I assumed that's the World Book way. They pick an expert and trust that the expert won't abuse the privilege."
He then stated,
- "I have not bought the latest set of World Books. In fact, having been selected to be an author in the World Book, I now believe that Wikipedia is a perfectly fine source for your information, because I know what the quality control is for real encyclopedias."
Every article in Wikipedia, even those on the most obscure topics, is subject to review by anyone who can read sources about the topic. But as well, highly experienced experts from many fields have written, reviewed, and updated articles, so the content of articles in fields like medicine, physics, computer science, or mathematics may be extremely detailed.
Wikipedia has a logistical advantage, with thousands of editors discussing and updating articles. This serves as an effective means of quickly detecting problems and updating articles – often within minutes or hours – to better reflect the documented sources. Occasional bottlenecks and conflicts occur when disputes arise between editors, but the danger of a sole "senior editor" clamping down on content, as happens in traditional encyclopedias, is much reduced.
A countervailing threat is posed when groups of editors collaborate to shift an article away from Wikipedian norms and values, and that situation requires longer to mediate. A common source of conflict is from slanted text fostered by tabloid journalism which introduces biased framing or misinformation into mainstream reports about a topic. Group content disputes have even led to the locking of articles, which then require changes to be agreed upon through deliberation. Once major news sources spread misinformation, it can be extremely difficult to prevent its propagation into the relevant Wikipedia articles. In some cases, both conflicting views are stated, as being undecided within the expert sources. However, among the nearly 6.6 million articles, relatively few have been affected by group disputes.
Each language-specific instance of Wikipedia has its own quality control procedures, but the major-language branches have similar policies and controls, such as to block further editing by repeat-troublemakers and review their edit-history contributions to undo any damage that may have been temporarily inflicted.