Question: A group of researchers is interested in the effectiveness of different social programs and therapies in helping reduce depression in the elderly. A random sample of 64 depressed community dwelling seniors is identified and each person is randomly assigned to one of four groups a) friendly visits from a volunteer b)meals on wheels c) treatment with antidepressant drugs and d) control, no intervention. 16 subjects are assigned to each group. After three months of receiving treatment, subjects are tested for depression.

ANONVA TABLE

SOURCE SS DF MS

BETWEEN 45 F= 6.67

b. with a= .05, give the critical f value

c. report the results formally

d. what should the researcher conclude based on these statistics

e. what is the proportion of variance explained/accounted for

f. calculate the HSD for the post hoc tests.