Evaluating Sources

Depending on your thesis, subject, and instructor guidelines, there are a range of sources you can use as support. Each source should be carefully examined and weighed for accuracy, value, and relevance. Too often we collect statistics, copy quotations, and present facts without questioning their validity.

EVALUATING SOURCES

BOOKS

In reviewing books, consider the following questions before you accept any or all of the author's conclusions.

*			What kind of book is it -- a factual account, a personal memoir, a general text? What does the author provide, a general overview of a situation, event, or problem or a specific analysis? Is the author of a book about John F. Kennedy a historian or a personal friend who worked in his administration? Does the book rely on facts, statistics, and surveys or personal observations and experiences?
*			Who is the author or authors? Does the book contain any biographical information about the author, such as his or her education, experience, or credentials? Search for the author on the Internet to locate biographical information. Is the writer a recognized authority? Has he or she published other works?
*			Is the author objective or subjective? Does the book reflect a bias?
*			When was the book published? Is the information still relevant?
*			Who published the book? Recognized publishers and university presses have editorial staffs that review books for accuracy and use of professional standards. Small presses may have defined political aims and publish materials that are little more than propaganda.
*			Can you locate reviews? Check the library reference room or conduct an Internet search to locate reviews of the book. How was it received by critics?
*			Does the author support his or her thesis with factual detail? Does the author provide citations?
*			Does the author exercise critical thinking? Does the book ignore alternative interpretations, overlook conflicting evidence, or draw conclusions on fragmentary details?

PERIODICALS

*			What is the nature of the magazine or newspaper? Quarterly academic and monthly professional journals are carefully edited. Articles are often subjected to peer review. Popular magazines are less rigorous and inaccurate or misleading information is more likely to slip past editors.
*			Do academic articles follow standard methods and cite sources? Does the author present enough support for his or her thesis?
*			Does the journal or newspaper have a bias? Many mainstream, academic, and professional journals attempt to remain objective, although individual articles may represent specific viewpoints. Other publications have clearly defined ideological agendas and only publish information supporting their opinions. If you are unsure of the publication, review as many copies as you can. Examine the articles, editorials, and letters to the editor for signs of of a consistent bias.
*			Can you verify newspaper reports from other sources? Newspaper reports are filed within hours of an event and can often contain factual errors. Use the Internet to locate other accounts or sources to verify the content of newspaper articles.

SURVEYS

We are often presented with statements that "eighty percent of Americans support capital punishment" or that "three out of four students support our proposal." Statements based on surveys should be examined carefully before accepting them as valid.

STATISTICS

Anyone conducting research is likely to encounter statistics. Statistics can be impressive and appear to provide conclusive proof of an author's thesis. But as with other sources, statistics have to be evaluated carefully to measure their reliability:

*			Where did the statistics come from? Who produced the statistics? Is the source reliable? Statistics about the safety of nuclear power plants released by utility companies or anti-nuclear organizations may be suspect. If the source might be biased, search for information from additional sources.
*			When were they collected? Information can become obsolete very quickly. Determine if the numbers are still relevant. For example, surveys about issues like capital punishment can be distorted if they are conducted after a violent crime.
*			How were the statistics collected? Public opinion polls are commonly used to represent support or opposition to an issue. A statement such as "Ninety percent of the student body think Dean Miller should resign" means nothing unless you know how that figure was determined. How many students were polled -- ten or a thousand? How were they chosen -- at an anti-Miller rally or by a random selection? How was the question worded -- was it objective or did it provoke a desired response? Did the polled students reflect the attitudes of the entire student body?
*			Are the units being counted properly defined? All statistics count some item -- drunk driving arrests, housing starts, defaulted loans, student drop outs, teenage pregnancies, or AIDS patients. In some cases confusion can occur if the items are not precisely defined. In polling students, for instance, the term "student" must be clearly delineated. Who will be counted? Only full-time students? Undergraduates? Senior citizens auditing an elective art history course? This is particularly a problem in social science. Unless there is a set definition of an "alcoholic" or a "juvenile delinquent", comparing studies will be meaningless.
*			Do the statistics measure what they claim to measure? The units being counted may not be accurate indicators. Comparing graduates' SAT scores assumes that the tests accurately measure achievement. If one nation's air force is 500% larger than its neighbors, does it mean that it is five times as powerful? Counting aircraft alone does not take quality, pilot skill, natural defenses, or a host of other factors into account.
*			Are enough statistics presented? One statistic may be accurate but misleading. The statement that "eighty percent of Amalgam workers own stock in the company" makes the firm sound employee-owned -- until you learn that that the average worker has half a dozen shares. Ninety percent of the stock could be held by a single investor.
*			How are the statistics being interpreted? Numbers alone do not tell the whole story. If one teacher has a higher retention rate than another, does it mean he or she is a better instructor or an easy grader? If the number of people receiving services from a social welfare agency increases, does it signal a failing economy or greater effort and efficiency on the part of an agency charged with aiding the disadvantaged?

USING SOURCES

There is no reason why you cannot use biased sources or questionable data -- as long as you note its weaknesses. Comment on the quality of sources you locate:

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From The Sundance Reader, Third Edition, Web Site by Mark Connelly.