Learning Objectives

After reading this chapter, you should be able to:

1. Identify the four steps of hypothesis testing.

2. Define null hypothesis, alternative hypothesis, level of significance, test statistic, p value, and statistical significance.

3. Define Type I error and Type II error, and identify the type of error that researchers control.

4. Calculate the one-sample z test and interpret the results.

5. Distinguish between a one-tailed test and a two-tailed test, and explain why a Type III error is possible only with one-tailed tests.

6. Elucidate effect size and compute a Cohen’s for the one-sample z test.

7. Define power and identify six factors that influence power.

8. Summarize the results of a one-sample z test in APA format.