What is a "Good" Source? Determining the Validity of Evidence

Terms and concepts to know for this lesson:

Validity - soundness and strength of argument. Is this evidence any good?

Audience - people who have read or will read a particular text, publication, or writer, considered collectively. For whom did the author intend to read or view this source?

Authority - power to inspire belief or weight of testimony. Does this person know what he or she is talking about? 

In the previous lesson Backing it Up: Using Evidence to Support a Rhetorical Argument, you learned why you need to use evidence to support your argument. But how can you determine if the source you're looking at is "good" evidence? 

Evaluating a Source

When we determine that a source is "good," we say that it has validity. But how can you determine if the source you're consulting is valid? Here's a couple of questions to consider:

• Who is the author of the source? What are his or her credentials - is her or she a recognized expert in the field? Are they representing an organization? If so, what is the organization's mission and goals? If you're unsure, try doing a Google search on the author or their organization.
• How did the source get its information? If the source includes references, look at a few of the references - do they look like reliable sources of information? Does it look like the author is citing the source correctly? Use your best judgment!
• What if the source you've found doesn't have references? If a source doesn't include references, see if you can fact check the information in other ways. For example, if you're looking at a news article that quotes experts in a field, do a Google search of the expert's name and see what information you can find on him or her.  

Types of Sources - Scholarly, Trade, & Popular

Previously, you might have been told to only use scholarly sources for research assignments. Why is that, and what does that term even mean?

 A scholarly source is written by an expert for other experts in the same field. Scholarly sources typically include references to other sources, and are written with the assumption that the audience already has significant background knowledge in the topic. Scholarly sources generally go through a process called "peer review," in which they are vetted by other experts. Scholarly sources generally are viewed as having the highest validity, but they can be daunting to examine by a reader unfamiliar with the field. 

 A trade source is written by a professional in a particularly industry for others in that same profession. However, while members in a profession work in the same industry broadly, individual professionals may have drastically different job responsibilities. As a result, while trade sources often assume the reader has some familiarity with topics, they generally are more accessible by a layperson than scholarly sources.

 A popular source is written for broad consumption; the author generally does not assume the audience will have extensive background knowledge on the topic. Consequently, these sources are the most accessible by a novice to a field, and can be a very great place to start researching a topic for an assignment.

Conclusion 

So what source types should you use in your research assignment? Depending on your topic, any and all of these source types might be appropriate to use and valid evidence to support your argument. Scholarly sources are generally perceived as stronger evidence than trade sources, and trade sources stronger than popular source; however, popular sources can be useful evidence as so long as you carefully consider the authority of the source's author. For example, a personal blog might be a great source of information on your research topic if the blog is run by a leading expert in the field.