Wikipedia:Plagiarism

This guideline addresses how to avoid plagiarism on Wikipedia and how to address it when it is encountered.

Plagiarism is the incorporation of someone else's work without providing adequate credit. Even if you have cited a source, make sure that your wording does not duplicate that of the source unless you note duplication by quotation marks or some other acceptable method (such as block quotations). This applies even if your source is not copyrighted.

An accusation of plagiarism is very serious. When dealing with plagiarism, take care to address the issue calmly and civilly. Focus on concerns about proper sourcing and copyright violations.

Definitions of plagiarism

Plagiarism isn't identical to copyright infringement. Material from the public domain still needs to be attributed properly.

Definitions of plagiarism differ. A very basic, plain-spoken definition is offered by Ann Lathrop and Kathleen Foss in their 2000 guide Student Cheating and Plagiarism in the Internet Era: A Wake-up Call: "If you didn't think of it and write it all on your own, and you didn't cite (or write down) the sources where you found the ideas or words, it's probably plagiarism." It doesn't matter where you find the information; even if your source is free content, you should acknowledge it.

Some definitions of plagiarism require that it be committed with the intent to deceive, while others do not. Wikipedia is more concerned with impact than intent; whether it is the result of deliberate deception or improper citation, duplicating the work of others without credit can bring both author and publisher into disrepute.

Editors should be aware that the precise definition of what consitutes plagiarism is often disputed both in academia and here on Wikipedia. You can always avoid any dispute by one of: rewriting text completely into your own words, using multiple referenced sources; directly quoting and referencing the material you copy; or properly attributing public domain text that you place directly into an article.

Why plagiarism is a problem

• A useful encyclopedia cites the sources of its content, so that readers may verify the information or seek further information from the source.

• A credible encyclopedia must not silently present content copied from elsewhere as though it were original.

• The correction of improperly copied content disrupts the encyclopedia and may require the deletion of all subsequent edits to the article.

• The silent inclusion of copied content poses legal problems for readers who re-use Wikipedia content, under the terms of the GNU Free Documentation License.

• Subject matter experts – particularly those from academia – may be discouraged from participating in (or endorsing) a project which fails to give proper credit to their work and the work of their colleagues.

Attributing text copied from other sources

Wikipedia draws clear distinctions between work submitted by Wikipedia editors as their own work (which can be "edited mercilessly"), work marked as a quotation (which must be properly credited and left essentially untouched), work described as a paraphrase of another source (which can be edited as long as the original sense is not lost), and direct copying of large blocks of free content written by other people (which should also be credited). In quotations, editorial notes and minor changes are sometimes useful, but must be clearly marked as such. See WP:MOSQUOTE for details.

Public domain or free license text

See also: Category:Attribution templates

Material from public domain and free sources is welcome on Wikipedia, but such material must be properly attributed. Such material need not be explicitly enclosed in block quotes, but there are often times when some or all of the material is best placed in explicit quotes. A passage that is explicitly enclosed in quotation marks and sourced by a footnote is properly attributed, because the original author is given credit for both the content and the wording.

An advantage of public domain or free license sources is that longer quotations are more acceptable than those from non-public sources, which may run afoul of "fair use" copyright limitations. (See the guidelines on quotation for information on formatting quotes.) A practice preferred by some wikipedia editors, when copying in public domain or free content verbatim, is to paste in the content in one edit, with indication in the edit summary of the source of the material. This practice has some advantages. This way, further changes such as modernizing language and correcting errors can be done in separate edits after the original insertion of text, allowing later editors the ability to make a clear comparison between the original source text and the current version in the article. In addition to the edit summary note, be sure to attribute the material either by using blockquotes or quotation marks, by using an attribution template, using an inline citation and/or adding your own note in the reference section of the article to indicate that language has been used verbatim. For an example of the latter, see the references section in planetary nomenclature [1], which uses a large amount of text from the Gazetteer of Planetary Nomenclature. Whether adding text verbatim, summarizing, paraphrasing or making explicit quotations, regular referencing should be added to provide both attribution and verifiability.

Public domain text copied into the article can be changed through the normal process of wiki editing; the article history will show the evolution of the text. Material within blockquotes and normal quotation marks should be left unaltered. Editors are free to rewrite or alter public domain material and remove part or all of a quoted passage, leaving just a reference footnote giving credit for the information. Public domain attribution notices should not be removed from an article or simply replaced with inline citations unless it is verified that all phrasing and information from the public domain source has been excised.

Text available under a free license

Some authors explicitly release their work under a free license. If the license of the material is compatible with the GFDL license of Wikipedia content, then it can be added directly to articles on Wikipedia; acceptable licenses include the GFDL (with no invariant sections or cover texts) and content granted into the public domain (release-all-rights). Creative Commons content is not currently approved for this purpose.

However, "free" license does not mean free of copyright concerns. For example, Wikipedia's contributors retain copyright to material they contribute here, though GFDL allows reuse and modification with proper attribution. If you contribute material under a free license, you must be sure that you comply with whatever licensing requirements exist. In all cases, the moral rights of the original authors whose works are copied must be respected during the term of their rights, which means that it is imperative that their work is distinguishable from the prose of the Wikipedia article. Because articles normally evolve through incremental changes, it is important to retain an anchor to the originally copied text so that subsequent changes can be traced.

Copying within Wikipedia

Wikipedia's content is dually licensed under both the GFDL and CC-BY license models. Contributors continue to own copyright to their contributions, but liberally license it for reuse and modification. GFDL and CC-BY do require attribution.

Language translations between various Wikimedia Foundation wikis are perfectly acceptable provided that the original source is clearly indicated, which satisfies the attribution requirement. This can be done via the edit summary and by putting a note on the article talk page with a link to the original source. See Wikipedia:Translation and Category:Interwiki translation templates.

When copying material within Wikipedia, from one article to another, attribution is also required. For guidelines on copying and moving material within Wikipedia itself, see WP:MERGE, WP:SPLIT and WP:SUMMARY.

Generating articles from a free source

In the past, Wikipedia has undertaken large projects in which many articles are generated from free sources. For instance, Encyclopaedia Britannica 1911 was used as a source to build many articles in 2002. These articles were marked with the {{1911}} template to make it clear that text had been taken from this source. Similar templates for other free content can be found at Category:Attribution templates. These templates are an accepted way to give credit to free content when that free content is used to build Wikipedia. Additions of this kind can be improved through the normal process of wiki editing.

Before engaging in any similar large-scale project of your own, be sure to discuss your ideas at Wikipedia:Village pump (proposals) and/or a relevant Wikiproject. Mass edits of this kind should always be discussed in advance to be sure that you are properly attributing your free source.

Attributing media copied from other sources

See also: Commons:Licensing

See also: Wikipedia:Image use policy

For images and other media, you must specify correct source and licensing information, otherwise they run the risk of deletion. In particular, you should never use {{PD-self}}, {{GFDL-self}} or {{self}} if the image isn't yours. If the source requests a credit line, e.g. "NASA/JPL/MSSS", you should put one in the author field of {{information}}.

What is not plagiarism

See also: Wikipedia:When to cite

It isn't always necessary to cite sources to avoid plagiarism. Here are some examples where attribution may not be required:

• Factual information found in infoboxes that is common knowledge. (Many infobox parameters do, however, include a feature enabling notes of sources of information to be placed in infoboxes where appropriate.)

• Simple, non-creative lists of information, such as a list of song titles on an album or actors appearing in a film. If creativity has gone into the selection of elements (in terms of which facts are included and in which order they are listed), then reproducing the list without attributing it as a quotation constitutes plagiarism (and may in any event constitute a copyright violation, see Feist Publications v. Rural Telephone Service).

• Statements of common knowledge, so long as you remember that using another person's words to discuss a topic that is common knowledge can still be plagiarism if you are copying their distinctive and original wording. In such a case, the source must be properly attributed and usually placed in quotation marks.

• Common expressions and idioms, such as "rags to riches" or "adding insult to injury".

• Mathematical formulas which are part of the general background knowledge of a field.

• Simple logical deductions. Complex logical deductions, in contrast, may require a citation.

How to find plagiarism

Text plagiarism

There are a number of methods to detect plagiarism. Plagiarized text often demonstrates a sudden change of style and tone from an editor's usual style and may appear more advanced in grammar and vocabulary. Plagiarized material may contain unexplained acronyms or technical jargon (that had been described in an earlier part of the plagiarized document). Because plagiarized material was written for other purposes, it is often slightly off topic or un-encyclopedic in tone. An editor who plagiarizes multiple sources will appear to change writing style abruptly.

An easy way to test for plagiarism of online sources is to cut and paste passages into a search engine. Exact matches or near matches may be plagiarism. When running such tests, be aware that some other websites reuse content from Wikipedia. A list of identified websites which do so is maintained at Wikipedia:Mirrors and forks. It is usually possible to find the exact version in article history from which a mirror copy was made. Conversely, if the text in question was added in one large edit, and the text closely matches the external source, this is an indication of direct copying. If in doubt, double check search engine results with an experienced Wikipedian.

Another option is to utilize a plagiarism detector. Plagiarism detection systems, some of which are freely available online, exist primarily to help detect academic fraud. Some such programs and services can be found at Category:Plagiarism detectors. Wikipedia does not endorse or recommend any external services, so your own experience will be the guide.

It can also be useful to do a direct comparison between cited sources and text within the article, to see if text has been plagiarized, including too-close paraphrasing of the original.

Media plagiarism

Investigating media plagiarism can begin with a commonsense question: does it seem likely that the uploader is the original source? Sometimes the answer to this will be obvious. The person who scans an image from an 1825 textbook on herbs is unlikely to be the author, even if they have claimed {{PD-self}}. Sometimes doubts may be triggered by the professional quality of media or by the exclusivity.

If you supect plagiarism, try to locate the original source through an online search engine such as Google Image Search. Even if you don't locate a previously published original, plagiarism may still exist. Other factors to consider include the editing history of the uploader and, with images, image metadata, such as EXIF and XMP.

Frequently a person who uploads and claims credit for another's image will leave the original image metadata or a visible or invisible digital watermark in place. If the author information conveyed by the metadata or watermark contradicts the author information on the image description page, this is a sign the image requires investigation. A user's original photographs can also be expected to have similar metadata, since most people own a small number of cameras; varied metadata is suspicious. Suspicions based on metadata should be checked with other editors experienced with images and other media.

How to respond to plagiarism

Failure to properly attribute text may be intentional, but it is often inadvertent. Avoiding plagiarism requires mastery of citation and paraphrasing. Contributors need to know when and how to cite sources. When paraphrasing, they need to know how much they can and should retain without following too closely on source text. They also need to remember when and where they saw something first, both in active research, while note taking, and during composition, to avoid unconscious plagiarism.

Contact the editor involved

An accusation of plagiarism is a serious charge. Please use care to frame concerns in an appropriate way. Even in blatant, conspicuous cases, it is important to remain civil. Given that attribution errors may be inadvertent, intentional plagiarism should not be presumed in the absence of strong evidence. Remember to start with the assumption of good faith. While it is essential that plagiarism problems be resolved, we also aim – wherever possible – to educate our editors, so that they may become better contributors to the encyclopedia.

Many editors are unaware that they have violated any guidelines when copying or closely paraphrasing published material. The best approach is to contact the editor and make sure they understand the requirements for attribution at English Wikipedia. Invite the editor to identify and repair any and all instances of plagiarism. Remember that they may not be familiar with the concept of plagiarism, and may be defensive when their prior edits are being challenged.

In the case of outright copyright violations, the editor should also be made aware of the applicable policies and law which forbid these. Simple plagiarism can be approached more gently.

Seek administrator assistance

If you find that an editor persists in plagiarising others' work after being notified of this guideline, report him or her at the administrators' noticeboard so that an administrator can respond to the issue. Be sure to include diffs which show both the plagiarism and warnings which were given and ignored.

Repairing plagiarism

Sometimes material from a copyrighted work is copied into Wikipedia with minimal rewriting. This may still be a violation of copyright as a derivative work, and the same concerns about plagiarism would apply if the phrases, concepts and ideas in the copied material are not attributed to the original author. If the text follows closely enough on the original in structure, presentation, and phrasing to raise copyright concerns, handle it as a copyright violation. If it does not, address it as plagiarism.

Plagiarism doesn't have to be immediately removed, unlike copyright violations. It does need to be properly attributed to its source. If you find an example of plagiarism, where an editor has copied text, media or figures into Wikipedia without proper attribution, contact the editor responsible, point them to this guideline page and ask them to provide the proper attribution. It may also be helpful to politely refer them to Wikipedia:Verifiability, Wikipedia:Citing sources, and/or Help:Citations quick reference. Editors who have difficulties or questions about this guidance can be referred to the Help Desk or media copyright questions.

You can also change the copied material or provide the attribution or source on your own. Material that is plagiarized but which does not violate copyright does not need to be removed from Wikipedia if it can be properly sourced. Add appropriate source information to the article or file page wherever possible. With text, you might move unsourced material to an article's talk page until sources can be found.

Copyright violations

Main page: Wikipedia:Copyright violations

See also: Wikipedia:Copyright problems, Wikipedia:Possibly unfree images, and Wikipedia:Image copyright tags

Direct copying of copyrighted works may be a copyright violation. Doing so without attribution is also plagiarism. Such additions can be dealt with either by attribution, turning it into a quote with a source, or by truncation or removal of the copied material. If you find an article where direct copying has occurred, do something. If the material is a copyright violation, remove it or tag the article with the {{copyvio}} template. If the copyrighted material used is brief, consider turning it into a properly attributed quotation according to our Wikipedia:Non-free content policy or rewriting it in your own original language. If you are uncertain if the material is a copyright violation, flag it with a template such as {{copypaste}} so that others can deal with it.

If you believe that an image or media file is a copyright infringement, please follow one of the processes at the guide to image deletion. Note that if the image is indisputably non-free and it can comply with our non-free content policy, you may be bold and retag it as a non-free image with an appropriate tag. If you are uncertain of the copyright status of an image or other media file, you may seek feedback at media copyright questions.

See also

• Wikipedia:Quotations (essay)
• Wikipedia:Wikipedia Signpost/2009-04-13/Dispatches – Wikipedia Signpost article on plagiarism

Further reading

Articles, books, and journals

Template:Ref indent Eisner, Caroline, and Martha Vicinus, eds. Originality, Imitation, and Plagiarism: Teaching Writing in the Digital Age. Ann Arbor: University of Michigan Press (Digitalculturebooks), 2008. Print. ISBN 9780472070343 (cloth). ISBN 9780472050345 (paper). "Originality, Imitation, and Plagiarism: About the Book". University of Michigan Press, 2008. Web. 12 Mar. 2009. ("This collection is a timely intervention in national debates about what constitutes original or plagiarized writing in the digital age.")

Jaschick, Scott. "Winning Hearts and Minds in War on Plagiarism". Inside Higher Ed 7 Apr. 2008. InsideHigherEd.com, ©2009. Web. 12 Mar. 2009.

Plagiary: Cross-Disciplinary Journal in Plagiarism, Fabrication, and Falsification. Ed. John P. Lesko (Saginaw Valley State University). Scholarly Publishing Office, University Library, University of Michigan, 2006–2008. Web. 12 Mar. 2009. ISSN 1559-3096. ("Publication of the Scholarly Publishing Office, University of Michigan Copyright Plagiary.org 2005–2008") Template:Ref indent-end

Digital academic resources

Template:Ref indent Cornell University. "Recognizing and Avoiding Plagiarism". College of Arts and Sciences, Cornell University, ©2005. Web. 12 Mar. 2009.

Duke University Libraries. "Citing Sources: Documentation Guidelines for Citing Sources and Avoiding Plagiarism". Duke University Libraries, (last modified) 2 June 2008. Web. 12 Mar. 2009. (Provides hyperlinked "Citation Guides" pertaining to the most commonly-used citation guidelines, including parenthetical referencing; includes: APA, Chicago, CSE, MLA, and Turabian style guidelines; such style guides define plagiarism and how to avoid it.)

Harvard College Library. "Research Guides". Harvard University Library, (last reviewed) 9 March 2009. Web. 12 Mar. 2009. (Compiled by the Staff of Harvard College Library.)

Indiana University at Bloomington. "Plagiarism: What It is and How to Recognize and Avoid It". Writing Tutorial Services, Campus Writing Program, Indiana University, (last updated) 27 Apr. 2004. Web. 12 Mar. 2009.

University of New South Wales. "Avoiding Plagiarism". The Learning Centre, Academic Skills Resources, University of New South Wales, (last updated) 24 Oct. 2008. 12 Mar. 2009. (Includes: "What Is Plagiarism?"; "Common Forms of Plagiarism"; and "Plagiarism & the Internet".) Template:Ref indent-end

External links

• FamousPlagiarists.com – Website published by John P. Lesko, associate professor of English at Saginaw Valley State University; editor of Plagiary (see "Further reading"). (Hyperlinked resources, including: a "glossary of terms" relating to plagiarism; a bibliography of "Books and Other Resources"; and profiles of "Famous Plagiarists". "Copyright 2004-2006 Famous Plagiarists.com / War On Plagiarism.org. Some Rights Reserved").
• The Plagiarism Checker – Facility for detecting student plagiarism at dustball.com. ("EDUC478: This educational software was designed as a project for the University of Maryland at College Park Department of Education." © Copyright 2002 by Brian Klug.)
• Plagiarism.org – By Turnitin (cited by Eisner and Vicinus [below]).
• "Read a Q&A with the editors on Inside Higher Education" – Interview with Caroline Eisner and Martha Vicinus, editors of Originality, Imitation, and Plagiarism, conducted on 3 Apr. 2008.