Wikipedia:Reliable sources/examples

From Wikipedia, the free encyclopedia

The following is a proposed Wikipedia policy, guideline, or process. The proposal may still be in development, under discussion, or in the process of gathering consensus for adoption. References or links to this page should not describe it as "policy".

A proposal's acceptance or rejection is not determined simply by counting votes.

This page provides examples of what editors on Wikipedia assess to be a reliable source, the advice is not, and cannot be, comprehensive so should be used to inform discussion in an article talk page with respect to sources. Exceptions can potentially be made however these should be avoided, use common sense when reaching a collaborative conclusion. Advice can be sought on the talk page of the guideline.

1 Use of statistical data
2 Advice by subject area
3 Use of electronic or online sources
4 See also

[edit] Use of statistical data

Statistical data may take the form of quantitative or qualitative material, analysis of each of these can require specialised training. Statistical data should be considered as a primary source and should be avoided. Misinterpretation of the material is easy and statistics are frequently reported in an ambiguous manner in the media so any secondary reference to statistical data should be treated with considerable care. The principles in the guideline should be rigorously applied to ensure that the references cited are a reasonable representation of the data.

The integrity of qualitative data depends on the questions used and the demographic make-up of the samples questioned, sound secondary sources will comment on the impact of the questioning strategy and the sample questioned and this should be referred to in the article.

See Misuse of statistics, Opinion poll, and Statistical survey for common errors and abuses.

[edit] Advice by subject area

[edit] History

The American Historical Review reviews around 1,000 books each year. The American Historical Association's Guide to Historical Literature (1995) summarizes the evaluations of 27,000 books and articles in all fields of history.

Historical research involves the collection of original or “primary” documents (the job of libraries and archives), the close reading of the documents, and their interpretation in terms of larger historical issues. In recent decades, many more primary documents (such as letters and papers of historical figures) have been made easily available in bound volumes or online. For instance, the Jefferson Papers project at Princeton begun in 1950 has just published volume 30, reaching February 1801. More recently, primary sources have been put online, such as the complete run of the London Times, the New York Times and other major newspapers. Some of these are proprietary and must be accessed through libraries; others, such as “Making of America”, which publishes 19th century magazines, are open to the public.

Scholars doing research publish their results in books and journal articles. The books are usually published by university presses or by commercial houses like W.W. Norton and Greenwood which emulate the university press standards. Reputable history books and journal articles always include footnotes and bibliographies giving the sources used in great detail. Most journals contain book reviews by scholars that evaluate the quality of new books, and usually summarize some of their new ideas. The American Historical Review (all fields of history) and Journal of American History (US history) each publish 1000 or more full-length reviews a year. Many of the major journals are online, as far back as 1885, especially through JSTOR.org. A good book or article will spell out the historiographical debates that are ongoing, and alert readers to other major studies.

On many topics, there are different interpretive schools which use the same documents and facts but use different frameworks and come to different conclusions. Useful access points include: scholar.google.com and books.google.com, and (through libraries) ABC-CLIO’s two abstract services, American: History and Life (for journal articles and book reviews dealing with the US and Canada), and Historical Abstracts (for the rest of the world.) Research libraries will hold paper guides to authoritative sources. The most useful is The American Historical Association's Guide to Historical Literature, edited by Mary Beth Norton and Pamela Gerardi 2 vol (1995), which is an annotated bibliography of authoritative sources in all fields of history.

In historical pages the user is assisted by having an annotated bibliography of the best resources. Users will often have to use inter-library loan to obtain books, so a short annotation explaining the value and POV of the book may be helpful.

There are many other sources of historical information, but their authority varies. A recent trend is a proliferation of specialized encyclopedias on historical topics. These are edited by experts who commission scholars to write the articles, and then review each article for quality control. They can be considered authoritative for Wikipedia. General encyclopedias, like the Encyclopedia Britannica or Encarta, sometimes have authoritative signed articles written by specialists and including references. However, unsigned entries are written in batches by freelancers and must be used with caution.

College textbooks are updated every few years, are evaluated by many specialists, and usually try to keep abreast of the scholarship, but they are often without footnotes and usually do not spell out the historiographical debates. Textbooks at the K-12 level do not try to be authoritative and should be avoided by Wikipedia editors. Every place has guide books, which usually contain a capsule history of the area, but the great majority do not pretend to be authoritative.

On many historical topics there are memoirs and oral histories that specialists consult with caution, for they are filled with stories that people wish to remember — and usually recall without going back to the original documentation. Editors should use them with caution.

The general public mostly gets its history from novels, films, TV shows, or tour guides at various sites. These sources are full of rumor and gossip and false or exaggerated tales. They tend to present rosy-colored histories in which the well-known names are portrayed heroically. Almost always editors can find much more authoritative sources.

See also Historiography

[edit] Physical sciences, mathematics and medicine

[edit] Cite peer-reviewed scientific publications and check community consensus

Scientific journals are the best place to find primary source articles about experiments, including medical studies. Any serious scientific journal is peer-reviewed. Many articles are excluded from peer-reviewed journals because they report what is in the opinion of the editors unimportant or questionable research. In particular be careful of material in a journal that is not peer-reviewed reporting material in a different field. (See the Marty Rimm and Sokal affairs.)

The fact that a statement is published in a refereed journal does not make it true. Even a well-designed experiment or study can produce flawed results or fall victim to deliberate fraud. (See the Retracted article on neurotoxicity of ecstasy and the Schön affair.)

Honesty and the policies of neutrality and No original research demand that we present the prevailing "scientific consensus". Polling a group of experts in the field wouldn't be practical for many editors but fortunately there is an easier way. The scientific consensus can be found in recent, authoritative review articles or textbooks and some forms of monographs.

There is sometimes no single prevailing view because the available evidence does not yet point to a single answer. Because Wikipedia not only aims to be accurate, but also useful, it tries to explain the theories and empirical justification for each school of thought, with reference to published sources. Editors must not, however, create arguments themselves in favor of, or against, any particular theory or position. See Wikipedia:No original research, which is policy. Although significant-minority views are welcome in Wikipedia, the views of tiny minorities need not be reported. (See Wikipedia:Neutral Point of View.)

Make readers aware of any uncertainty or controversy. A well-referenced article will point to specific journal articles or specific theories proposed by specific researchers.

[edit] In science, avoid citing the popular press

The popular press generally does not cover science well. Articles in newspapers and popular magazines generally lack the context to judge experimental results. They tend to overemphasize the certainty of any result, for instance presenting a new experimental medicine as the "discovery of the cure" of a disease. Also, newspapers and magazines frequently publish articles about scientific results before those results have been peer-reviewed or reproduced by other experimenters. They also tend not to report adequately on the methodology of scientific work, or the degree of experimental error. Thus, popular newspaper and magazine sources are generally not reliable sources for science and medicine articles.

What can a popular-press article on scientific research provide? Often, the most useful thing is the name of the head researcher involved in a project, and the name of his or her institution. For instance, a newspaper article quoting Joe Smith of the Woods Hole Oceanographic Institution regarding whales' response to sonar gives you a strong suggestion of where to go to find more: look up his work on the subject. Rather than citing the newspaper article, cite his published papers.

[edit] Which science journals are reputable?

One method to determine which journals are held in high esteem by scientists is to look at impact factor ratings, which track how many times a given journal is cited by articles in other publications. Be aware, however, that these impact factors are not necessarily valid for all academic fields and specialties.

In general, journals published by prominent scientific societies are of better quality than those produced by commercial publishers. The American Association for the Advancement of Science's journal Science is among the most highly regarded; the journals Nature and Cell are notable non-society publications.

Keep in mind that even a reputable journal may occasionally post a retraction of an experimental result. Articles may be selected on the grounds that they are interesting or highly promising, not merely because they seem reliable.

[edit] arXiv preprints and conference abstracts

There are a growing number of sources on the web that publish preprints of articles and conference abstracts, the most popular of these being arXiv. Such websites exercise no editorial control over papers published there. For this reason, arXiv (or similar) preprints and conference abstracts should be considered to be self-published, as they have not been published by a third-party source, and should be treated in the same way as other self-published material. See the section above on self-published sources. Most of them are also primary sources, to be treated with the caution as described in various sections of this guideline.

Researchers may publish on arXiv for different reasons: to establish priority in a competitive field, to make available newly developed methods to the scientific community while the publication is undergoing peer-review (a specially lengthy process in mathematics), and sometimes to publish a paper that has been rejected from several journals or to bypass peer-review for publications of dubious quality. Editors should be aware that preprints in such collections, like those in the arXiv collection, may or may not be accepted by the journal for which they were written — in some cases they are written solely for the arXiv and are never submitted elsewhere for publication. Similarly, material presented at a conference may not merit publication in a scientific journal.

[edit] Evaluating experiments and studies

There are techniques that scientists use to prevent common errors, and to help others replicate results. Some characteristics to look for are experimental control (such as placebo controls), and double-blind methods for medical studies. Detail about the design and implementation of the experiment should be available, as well as raw data. Reliable studies don't just present conclusions.

[edit] Law

There are several legal structures for the creation, validation and enforcement of law and the resulting corpus of law is only valid in the jurisdiction of origin. The opinion of experts within the jurisdiction is therefore preferred, in general, to that of outside commentators. Legal material may also be divided into the legal statement itself, material to support or inform that legal statement and judgements of opinion when applying the law in practice.

When discussing legal texts, it is more reliable to quote from the text, appropriately qualified jurists or textbooks than from newspaper reporting.

[edit] Business and Commerce

Material published by a trading organisation is a view of how that organisation looks on itself however it will also have a marketing component and may lack neutrality. If this material is used it should carry a caveat to indicate this risk and should be corroborated with independent reporting if possible. The accounts and notes to the accounts for all publically listed companies are required to have been independently audited and will contain a statement to that effect, possibly with caveats considered significant by the auditors. Smaller companies and partnerships which are not publically listed may have audited accounts. These accounts should provide a reliable view as to the financial health of the organisation however this is subject to the accounting principles applied, which should be identified in the notes. Due to the specialised skills required to assess financial health this material should not be used in isolation, a more acceptable judgement of the organisation can be obtained from investment analysis conducted in some segments of the business press, stock markets and significant investment vehicles. It should be noted that in some cases these assessments may be confidential.

Any judgements in Wikipedia with regard to trading organisations should be explicitly referenced and caveated with comments as to the reliability and range of sources used.

[edit] Crime Statistics

Crime statistics may detail crime reported to the police, crime recorded by the police (crime reports may not be recorded at the discretion of police), or crime experienced by the public - whether reported or not (determined by survey). Different police departments will have different rules for how to categorise and whether to record crime. This varies from country to country.

Where multiple crimes are committed in a single event, it is common to record only the most serious offense. In some countries, Police department districts may differ from municipal boundaries. Police crime recording rules are often revised leading to a problem in comparing crime rates from one year to another.

As a result, use of summarised crime statistics from raw data to indicate the criminality of a certain area in comparison with others or the prevalence of a certain type of crime constitutes original research. Editors should use reliable secondary sources for commentary on trends in the criminality or peacefulness of a district.

[edit] Popular culture and fiction

Articles related to popular culture and fiction must be backed up by reliable sources like all other articles. However, due to the subject matter, many may not be discussed in the same academic contexts as science, law, philosophy and so on; it is common that plot analysis and criticism, for instance, may only be found in what would otherwise be considered unreliable sources. Personal websites, wikis, and posts on bulletin boards, Usenet and blogs should still not be used as secondary sources. When a substantial body of material is available the best material available is acceptable, especially when comments on its reliability are included.

[edit] Use of electronic or online sources

Material from bulletin boards and forum sites, Usenet, wikis, blogs and comments associated with blog entries should not be used as sources. These media do not have adequate levels of editorial oversight or author credibility and lack assured persistence.

An Internet forum with identifiable, expert and credible moderators with a declared corrective moderation policy may , exceptionally, be considered reliable for some topics. In this sense, where moderators act as editors to review material, and challenge or correct any factual errors could have an adequate level of integrity. This exception would only be appropriate to fields that are not well covered by print sources, where experts traditionally publish online.

Trivia on sites such as IMDb or FunTrivia should not be used as sources. These media do not have adequate levels of editorial oversight or author credibility and lack assured persistence.

Exceptionally film credits on IMDb, which are provided by the Writer's Guild of America, can be considered to be adequately reliable.

Websites and publications of political parties, religious groups, anti-religious groups, or any other partisan group, may exhibit bias and should be treated with caution. Neither political affiliation nor religious belief stated in these sources are in themselves a reason not to use them, as these websites can be used to present the viewpoints of these groups, if properly attributed. Such sources should be presented alongside references from other sources in order to maintain a neutral point of view.

Websites and publications of trading companies, organisations and charities are a marketing communication channel and should be treated with caution. These media can be considered as primary data about the organisations view of itself but has clear bias related to commercial interests. Effort should be made to corroborate the reference with an independent source in order to maintain a neutral point of view.

Accounts and Notes to the Accounts in an annual report, which have been independently audited, can be considered as a secondary source with respect to the organisation and has some level of reliability. The process of audit provides a degree of editorial oversight although the statement by the auditors may contain caveats which should be borne in mind when using the material. Accounts should identify the accounting policies used which will increase the perceived level of reliability.

Widely acknowledged extremist organizations or individuals, whether of a political, religious, racist, or other character, should be used only as primary sources; that is, they should only be used in articles about those organizations or individuals and their activities. Even then they should be used with caution.