Children’s recall of TV ads. Refer to the Journal of Advertising (Spring 2006) study of children’s recall of television commercials, Exercise 9.17 (p. 477). You used a small-sample t test to test the null hypothesis H0: 1m1-m22 = 0, where m1 = mean number of ads recalled by children in the video-only group and m2 = mean number of ads recalled by children in the A>V group. LO3 Summary statistics for the study are reproduced in the table.
The validity of the inference derived from the test is based on the assumption of equal group variances, i.e., s1 2 = s2 2 .
Video-Only Group A/V Group n1 = 20 n2 = 20 x1 = 3.70 x2 = 3.30 s1 = 1.98 s2 = 2.13

a. Set up the null and alternative hypothesis for testing this assumption.

b. Compute the test statistic.

c. Find the rejection region for the test using a = .10.

d. Make the appropriate conclusion, in the words of the problem.

e. Comment on the validity of the inference derived about the difference in population means in Exercise 9.17.