Recent research indicates that the effectiveness of antidepr

Recent research indicates that the effectiveness of antidepressant medication is directly related to the severity of the depression (Khan, Brodhead, Kolts, & Brown, 2005). Based on pre-treatment depression scores, patients were divided into four groups based on their level of depression. After receiving the antidepressant medication, depression scores were recorded for each patient. The following data are similar to the results of the study. Write the null (H0) and alternative (H1) hypotheses: Determine the degree of freedom: total, between, and within; Determine the critical value with a = .05 Determine the sum of squares: total, between, and within: Determine the mean squares: between and within: Calculate the F statistic: Decision: Compute eta^2, the percentage of variance explained by the group differences:

Solution