Chapter 11

What does independent samples mean? Can you give an example of an experiment with independent samples?

What statistical test do we use when doing an independent samples experiment with two conditions?

What is the null hypothesis when you have an independent samples experiment? What is the alternative/research hypothesis?

How do you increase power in an independent samples experiment?

Be able to read SPSS output for an independent samples t-test. How do you know if t is significant?

What is the confidence interval of the difference? Be able to report and explain it.

What is “effect size”? What does this term tell us?  What are the guidelines for small, medium, and large effect size? Be able to report and explain it.

Be able to perform and interpret any SPSS procedures that we do for this chapter. That includes: entering data, choosing the test, interpreting the results, and reporting the correct output. Be able to create a bar graph of the means of the two conditions with error bars.

For t-tests in general:

What is the general logic of a t-test?

Know when to do a one-sample t-test, a paired-samples t-test, and an independent samples t-test (and a z-test).

Know when to use a two-tailed vs. a one-tailed test.

Be able to perform and interpret any SPSS procedures that we do for this chapter.