Evaluating Sources of Information

Why Evaluate?

Once you have found Information Packages (Sources of Information) matching the topic and requirements of your research, part of your Research Strategy should be to critically think about or evaluate these information sources. Just because a book, article, or Web document matches your search criteria and thus seems, at face value, to be relevant, does not mean that it is necessarily a reliable source of information. Frauds, hoaxes and quackery are nothing new. See, for example, the Skeptic's Dictionary and Quackwatch. And consider this - is everybody really an expert? For example, see ExpertCentral.com.

It is important to remember that sources of information comprising the Library's print and electronic collections (part of the "invisible" Web) have already been evaluated for inclusion among the Library's resources. This does not necessarily apply to sources of information on the ("visible") Web for the general public. Many of us with Internet/Web accounts are potential publishers on the visible Web, most of the content of which is published without editorial review. Think about it.

Questions to Ask

What criteria should you use to judge information sources? Summarizing some of the items listed under Evaluation Resources, below, the following questions should be asked when evaluating a source of information:

Who is responsible for publishing the information provided by the source? What are the credentials and affiliation or sponsorship of any named individuals or organizations? How objective, reliable, and authoritative are they? Is the author or contact person listed with addresses (street, e-mail)?

What can be said about the content, context, style, structure, completeness and accuracy of the information provided by the source? Are any conclusions offered? If so, based on what evidence and supported by what secondary and primary documentation? What is implied by the content? Is the content relevant to your information needs?

When was the information provided by the source published? Is the information provided by the source in its original form or has it been revised? Is this information updated regularly?

Where else can the information provided by the source be found? Is this information authentic? Is this information unique or has it been copied?

Why was the information provided by the source published? What are the perspectives, opinions, assumptions and biases of whoever is responsible for this information? Is anything being sold? Who is the intended audience?

Where to Look for Answers

Books and Articles

An initial evaluation of books and articles can be done by examining their bibliographic citations provided in library catalogs (such as the PAC) or periodical indexes and databases, containing brief author, publisher and date of publication information. Once you have found the book or article, look for additional information about the author(s) or publisher. If little or no biographical information is provided about the author(s), ask a reference librarian for Research Assistance.

The librarian may also be able to help you find book reviews.

Web Documents

Ideally, Web documents will include the following elements which can be used in the evaluation process:

Author or contact person with addresses (street, e-mail)
Document Uniform Resource Locator (URL), including an institutional identifier (e.g., an edu with a URL identifies the sponsoring institution as an educational institution)
Date of creation or revision
Link to sponsoring institution Web site

For more information on evaluating Web documents, see:

For exercises in evaluating Web documents, see Evaluating Sources of Information: Sample Web Documents.

Evaluation Resources

Help evaluating Web documents is provided by the following authors. In addition to Evaluating Sources of Information: Sample Web Documents, examples of Web documents for evaluation are provided by Alexander and Tate, Beck, Grassian, Henderson, Jacobson and Cohen, and Lesley University.

Jan Alexander and Marsha Tate, Widener University, provide Evaluation Checklists for advocacy, business/marketing, news, informational, and personal home Web documents. See Actual Web Pages as Examples.
Susan Beck, New Mexico State University, lists major Evaluation Criteria. See Examples.
Esther Grassian, UCLA College Library, lists many points to consider when Thinking Critically about World Wide Web Resources. See Hoax? Scholarly Research? Personal Opinion? You Decide! for examples. See also Who Dunnit: What Kind of Web Page Is This??
John R. Henderson, Ithaca College, provides six suggestions when looking at Web pages in his ICYouSee guide to critical thinking about the Web. See the pop quiz and one more st*p*d assignment for examples.
Trudi E. Jacobson and Laura B. Cohen, University at Albany, devised their own fake Web site in association with their Teaching Students to Evaluate Internet Sites Web site.
Lesley University has a Web page that provides criteria for Evaluating Web Sites, as well as example Web sites.
Joan Ormondroyd, Michael Engle and Tony Cosgrave, Cornell University, offer general suggestions on How to Critically Analyze Information Sources.
Hope N. Tillman, Babson College, addresses issues related to Evaluating Quality on the Net.
The University of California, Berkeley, Library provides information on Evaluating Web Pages: Why and How

Additional resources, in print and electronic format, on evaluating Web documents are listed at the following Web sites:

Dr. T.Matthew Ciolek's and Irena M. Goltz's Information Quality WWW Virtual Library, and
Nicole Auer's Bibliography on Evaluating Internet Resources.