You used a small-sample t-test to test the null hypothesis H0: (µ1 - µ2) = 0, where µ1 = mean number of ads recalled by children in the video only group and µ2 = mean number of ads recalled by children in the A/V group. Summary statistics for the study are reproduced in the table below. The validity of the inference derived from the test is based on the assumption of equal group variances, i.e., σ21 = σ22.
a. Set up the null and alternative hypotheses for testing this assumption.
b. Compute the test statistic.
c. Find the rejection region for the test using α = .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 8.15.
For Information: Refer to the Journal of Advertising (Spring 2006) study of children's recall of television commercials. Exercise 8.15.

Video Only Group N Group a 3.70 1.98 3.30 2.13