Three groups of students, 5 in each group, were receiving therapy for severe tes
ID: 3233785 • Letter: T
Question
Three groups of students, 5 in each group, were receiving therapy for severe test anxiety. Group 1 received 5 hours of therapy, group 2 received 10 hours and group 3 received 15 hours of therapy. At the end of therapy each subject completed an evaluation of test anxiety. Did the amount of therapy have an effect on the level of test anxiety?
The three groups of students received the following scores on the Test Anxiety Index (TAI) at the end of treatment.
TAI Scores for Three Groups of Students
Group 1 - 5 hours
Group 2 - 10 hours
Group 3 - 15 hours
48
55
51
50
52
52
53
53
50
52
55
53
50
53
50
What is your computed answer? (attach printout, on it circle the appropriate information, and please write the statistical response below)
What would be the null hypothesis in this study?
Is there a significant difference between any of the groups? If so, which groups?
TAI Scores for Three Groups of Students
Group 1 - 5 hours
Group 2 - 10 hours
Group 3 - 15 hours
48
55
51
50
52
52
53
53
50
52
55
53
50
53
50
Explanation / Answer
Ho: All means are equal
Ha: At least two of the means are signficantly different
Since the p- value < 0.05, we reject Ho
There is evidence that at least two of the three means are significantly different
From the post-hoc analysis we find that Group 2 is significantky different from groups 1 and 3.
One factor ANOVA Mean n Std. Dev 50.6 5 1.95 Group 1 - 5 hours 53.6 5 1.34 Group 2 - 10 hours 51.2 5 1.30 Group 3 - 15 hours 51.8 15 1.97 Total ANOVA table Source SS df MS F p-value Treatment 25.20 2 12.600 5.18 .0239 Error 29.20 12 2.433 Total 54.40 14