Evaluating evidence
When constructing an argument you need to evaluate any evidence or sources you read.
Ask yourself:
- Is it current or original? Remember that new research can appear at any time
- How do you know that it is true?
- How reliable is the source?
- Is there a motive bias behind it?
- Do the reasons support the conclusion?
- Does it contradict other evidence?
- Are the examples given representative of the whole area?
- Is there any other possible explanation?
- Does it match what you already know?
- What are they not telling you?
Check the references the writer has made:
- Who have they referenced?
- Is the work well respected?
- Are there primary or secondary sources?
Relevant and irrelevant evidence
Read the passage below. Do you think the evidence supports the conclusion?
People need to improve their understanding of how language works so that they can use it more effectively. Research studies (Bloggs, 2003; Bloggs, 2006) show that the study of a foreign language improves our understanding of the structure of language, providing a way of comparing different language structures. Therefore, people who only speak one language should be encouraged to study a second language.
Example statement 1
Does the evidence support the conclusion?
We could conclude from this that the evidence does support the conclusion.
People need to improve their understanding of how language works so that they can use it more effectively. Research studies (Bloggs, 2003; Bloggs, 2006) show that many people cannot describe the different components of their own language. A surprising number of people have difficulties remembering the rules even of their mother tongue. Therefore, people who only speak one language should be encouraged to study a second language.
Example statement 2
Does the evidence support the conclusion?
Evidence might suggest people having difficulties with their own language shouldn’t learn a second. It is relevant, but doesn’t support the argument. Further evidence would be needed to support the conclusion.
So, evidence needs to a. be relevant, and b. support the conclusion/argument.
Ways to evaluate sources
Use these techniques when researching a topic:
- Browsing: are they relevant and reputable?
- Focusing on relevant items: how do these support your line of reasoning?
- Selecting and evaluating a small number of sources: weighing the evidence and arguments; looking for flaws and gaps
- Comparing and contrasting different sources and checking for inconsistencies