Question: A research study was conducted to examine the clinical efficacy of a new antidepressant. Depressed patients were randomly assigned to one of three groups: a placebo group, a group that received a low dose of the drug, and a group that received a moderate dose of the drug. After four weeks of treatment, the patients completed the Beck Depression Inventory. The higher the score, the more depressed the patient. The data are presented below. Compute the appropriate test.

a. What type of test should you use to assess differences between these treatments and why? (2 points)

b. Run that test by hand or using SPSS, providing me with copies of your interpreted output. Are the survivorship times equal in the three groups? (4 points)