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7.5 Evaluating Sources

Learning Objectives

  1. Know how to ascertain if the information a source offers is relevant to your topic and current enough to use.
  2. Comprehend whether information is objective, reasonable and accurate.
  3. Understand how to determine if a source is credible.

Returning to Jacoba’s project, we can see that each type of genre she might use to write her essay on Social Security will require different questions to ask, sources to pursue, evidence and support to use.

Genre Informative Essays Interpretive Essays Persuasive Essays Problem-Solving Essays
Questions to ask What are the present facts about Social Security and its solvency? What has Social Security meant to American history, culture, politics, and government? Should Social Security be saved or phased out? Assuming it’s worth saving, how can we preserve Social Security in a way that doesn’t put us in more debt?
Types of sources Government budget figures, projections, and reports Historical records from the 1930s forward Editorials and position papers from policy experts and think tanks Articles and book-length works on fiscal policy and government entitlements
Evidence and support Demographics, actuarial tables, and economic statistics Political speeches and advertisements, congressional and presidential records Arguments from Social Security proponents and opponents Policy recommendations and proposals

The more Jacoba reflects on the kind of research she wants to spend her time conducting and the kind of writing she’s most comfortable doing, the better off she’ll be.

When you evaluate a source, you need to consider the seven core points shown in Figure 7.2.

Figure 7.2

A source is relevant if it can contribute to your paper in a meaningful way, which might include any of the following:

  • Supplies support for core argument(s)
  • Adds a sense of authority to your argument(s)
  • Contributes background information
  • Provides other viewpoints
  • Offers definitions and explanations that your audience will need for clarification

When determining if a source is current enough to use, a general rule of thumb is that a source must be no more than ten years old. In some situations, very few sources exist that were published within the last ten years, so older sources can be used as long as you explain why the use of the older sources is acceptable and meaningful. Or perhaps you may be using older sources to establish a historical record of thoughts and statements on your issue in question.

Before you use a source, you need to satisfy yourself that the information is accurate. In print sources, you can use the author (if known) and the publisher to help you decide. If you think the author and publisher are legitimate sources, then you are probably safe in assuming that their work is accurate. In the case of online information, in addition to considering the author and publisher, you can look at how long ago the site was updated, if evidence is provided to back up statements, and if the information appears to be thorough. For either print or online sources, you can check accuracy by finding other sources that support the facts in question.

You can deem a source to be reasonable if it makes overall sense as you read through it. In other words, use your personal judgment to determine if you think the information the source provides sounds plausible.

Reliable sources do not show biasPrejudice or a nonobjective stance. or conflict of interestA situation where a person or organization might personally benefit from his, her, or its public actions or influence.. For example, don’t choose a toy company’s site for information about toys that are best for children. If you are unsure about the reliability of a source, check to see if it includes a list of references, and then track down a sampling of those references. Also, check the publisher. Reliable publishers rarely involve themselves with unreliable information.

A source is objective if it provides both sides of an argument or more than one viewpoint. Although you can use sources that do not provide more than one viewpoint, you need to balance them with sources that provide other viewpoints.

.edu Educational
.com Commercial, for-profit, business
.gov Government
.mil Military
.net Network
.org Not-for-profit organization

A credible source is one that has solid backing by a reputable person or organization with the authority and expertise to present the information. When you haven’t heard of an author, you can often judge whether an author is credible by reading his or her biography. If no biography is available, you can research the author yourself. You can also judge the credibility of an online source by looking at address extensionThe last three letters in an Internet address (e.g., .com and .edu).. As a rule, you need to be aware that .com sites are commercial, for-profit sites that might offer a biased viewpoint, and .org sites are likely to have an agenda. Take precautions not to be fooled by an address extension that you think would belong to a credible source. Always think and read critically so you aren’t fooled.

Key Takeaways

  • A source is relevant to your topic if it supports your argument, adds a sense of authority to your argument, contributes background information, provides a different viewpoint, or offers key knowledge the audience will need. As a general rule, unless you are working with a subject that requires some historical research, a source should be no older than ten years.
  • Information within a source needs to be accurate, reasonable, reliable, and objective. Accurate means that the facts are correct, reasonable means it makes basic sense to you, reliable means it is without bias or conflict of interest, and objective means it presents more than one viewpoint.
  • A source is credible if the source has the expertise to present the information.


  1. Choose a research topic of interest to you. Find one source that is both related to the overall topic and relevant to your specific topic. Describe the relevant role the source could make (support, authority, background, viewpoints, or knowledge). Find a second source that is related to the overall topic but not as relevant to your specific topic.
  2. Find a source that you think is not acceptable due to not being accurate, reasonable, reliable, or objective. Share the source with your classmates and explain why you have deemed the source as unacceptable.
  3. Choose a research topic of interest to you. Find two sources with information that relate to your topic—one that is credible and one that is not credible. Explain what makes one credible and the other not credible.