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Navigating Library Research: Unit 7: Evaluating Sources

Quiz: Evaluating Sources

Test what you've learned in Unit 7.  Please download the following quiz, complete it, and return it directly to your instructor.

Evaluating Sources

Learning to evaluate sources well is one of the most important research skills for students of all levels. In this unit, you will learn to identify sources that are authoritative enough for academic research, and also those that are appropriate for more specific types of assignments. You will learn to assess five characteristics of sources:

  • Authority
  • Bias and perspective
  • Documentation
  • Review process
  • Timeliness

You will also learn appropriate usage of one of today's most popular sources, Wikipedia.


In library language, "authority" refers to whether a resource comes from an author or group that we believe we can trust. For example, if you were researching asthma, a librarian would recommend that you took your information from articles, books, or Web pages written by experts in the field. It could be dangerous to use advice from some random person online.

Here are some questions to help you identify authoritative sources:

  • What are the author's credentials?
  • Does the author have expertise on the subject?
  • What degree(s) does(do) the author(s) hold? From what college or university?
  • Is the author a member of professional organizations?
  • Are they affiliated with any of the following: a university or college, government agency, publisher or press, or their own company?

Authoritative sources will list the author's credentials. For instance, reputable medical Web sites mention where the doctor who wrote the page earned his or her degree, and where he or she is currently employed. If an individual maintains the site (such as a personal blog), you may want to verify that he or she is actually employed at the place mentioned. Most universities, major hospitals, and other organizations have staff lists online.

Pages maintained by an organization (such as the American Heart Association) do not always name an individual author for each page. However, these organizations clearly mark each page with their name. Check the very bottom of the page to look for this. You should find a statement such as "(c) 2010 American Heart Association."

Many Internet sources do not give the identity or credentials of the author or producer. These Web sites may have questionable authority.

Bias and Perspective

Recognizing authors' biases or slanted perspectives can be one of the most challenging aspects of evaluating a source. Sometimes it's obvious--for instance, materials produced by PETA (People for the Ethical Treatment of Animals) will have a different perspective on fur coat production than materials produced by a fur coat manufacturer. Speehes on universal health care given by a Democrat and a Republican will probably have notably different biases.

The more challenging situation comes when the author does not identify any affiliations. When you read an article in The Washington Post, the author typically does not say, "By the way, I'm a middle-of-the-road Republican." A doctor who designed a new diet program may not mention that hers is only one of many alternatives. This is why you need to learn to identify authors' biases on your own.

Bias is not necessarily a bad thing. It's just something to be aware of. If you're preparing to write a paper with a particular perspective (such as one that persuades your audience that making fur coats is unethical), you'll want to be able to find sources that have a perspective similar to yours. It's also helpful to be able to find materials with different perspectives, so you'll know what the opposition is saying.

Here are some factors to consider while you're determining a source's bias:

  • Is the information presented indended to inform, persuade, present opinions, report research, or sell a product?
  • For what audience is it intended? Readers of a magazine with a particular slant? Scholarly colleagues in a certain field? Attendees of an event?
  • Does it show any bias through connotative language or pointed examples?

 Even with all these clues in mind, this skill set can be tricky. Remember that you can always ask your professor or a librarian for help!


Documentation refers to evidence of where an author got his or her information. It is one of the most important steps in determining whether a source is appropriate to use for your research.

If you're catching up on the latest celebrity gossip, you may not really care where a reporter learned what he or she claims to know. However, if you're researching for an anthropology class paper, you'll want to know! This demonstrates one of the biggest differences between popular and scholarly sources. Often your professor will require that you use popular sources, scholarly sources, or both for an assignment. Popular sources are written for a general audience. They often do not tell you where they got every piece of information. Look at an article from People or Time Magazine. There is very rarely a bibliography or a list of works cited at the end of their articles. Although these sources are worth reading in many situations, they're not always appropriate for your research. Scholarly sources always tell you where their information came from. There will be a list of the materials the author refers to, generally at the end of the article.

Web pages can be more challenging for determining documentation. They can have all sorts of layouts, unlike scholarly articles. Here are a few things to look for:

  • Does the author refer to other works?
  • Does the Web page provide related links?
  • Is a bibliography provided?
  • Does the author support statements with data or references?

The Review Process

Scholarly publications are typically peer reviewed. The peer review process involves having several experts fact-check and approve of each article before it is published. If a journal is peer reviewed, it will typically have a statement about its review process on the back of the title page of each issue. Generally there is a list of all the reviewers and their affiliations. If you are looking at articles online, you can usually find information about the review process on each journal's Web site.

Many Internet sources are not reviewed before being posted; however, most government, educational, and organizational sites have some sort of review process. If no review process is stated or evident, assume there is none.


Evaluating the timeliness of a source helps you make several important choices. Here are two questions to ask as you begin evaluating:

  • When was the information published?
  • When was the web site last updated?

Different subject areas have different needs in terms of timeliness. In some subject areas, information stays relevant over time; in others, it does not. For example, if you are researching Shakespeare's Hamlet, reading an article written in 1915 could be useful and appropriate. However, if you're studying pediatric nursing, you'd probably rather have advice from the past few years. Learning to judge this area of timeliness just takes experience. Ask your professor or a librarian if you need advice.

Timeliness has additional implications for online sources. You've probably had the experience of using a Web page that hadn't been updated in a long time, and had lots of broken links. And while the page may look modern and pretty, there can be a great deal of outdated information. Develop the practice of looking for a "last updated" date whenever you look at a Web page for research purposes. Most informational sites list the date at the bottom, often in a corner.


Wikipedia is not a bad word in libraries. Librarians like Wikipedia, too. They just want you to know how to use it, and how not to use it, for academic research. Anyone can write or edit articles on the site, so there's no guarantee that any information there is correct, even if the author claims to have done detailed research. Below are hints on appropriate usage.

Ways to Use Wikipedia

  • Pop culture references: Very occasionally, Wikipedia is the best place for information. If your professor asks you to analyze a current TV show, recent album, etc., Wikipedia may have the most comprehensive information. Try finding an official site for the show or album first. (Wikipedia's articles often link to these pages.) Also, try to verify any information you take from Wikipedia in another source.
  • Looking up obscure or unfamiliar information: A news story you're reading mentions the legend of the Seven Pagodas of Mahabalipuram. You have no idea what this is or what culture it came from. Wikipedia can help you figure that out so you can later choose an appropriate regional folklore resource.
  • Looking for links to authoritative information: Wikipedias often has excellent lists of references and external links at the end of articles. You can use these to verify facts you found in the Wikipedia articles and look for additional information.

Ways Not to Use Wikipedia

  • Wikipedia is not meant to be a research tool for college students. Instead, use it to figure out how to find the research you need in authoritative sources.

Using Wikipedia for Academic Research