After reading this chapter, you should be able to:

1. Describe the between-subjects design, and identify two appropriate sampling methods used to select independent samples.

2. Calculate the degrees of freedom for a two-independent-sample t test and locate critical values in the t table.

3. Identify the assumptions for a two-independent-sample t test.

4. Compute a two-independent-sample t test and interpret the results.

5. Compute and interpret effect size and proportion of variance for a two-independent-sample t test.

6. Compute and interpret confidence intervals for a two-independent-sample t test.

7. Summarize the results of a two-independent-sample t test in APA format.

8. Compute a two-independent-sample t test and identify confidence intervals using SPSS.