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 d 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.