A school psychologist is interested in estimating the effectiveness of an antidrug film on the attitudes of eight-grade students. Each students' antidrug attitude is measured on a scale from 0 to 20 (20 representing the strongest opposition to drug use) at four times: the day before the film; as students are sitting in class waiting for the film to start; immediately after the film; and the next day in class. The data for 5 students appear in the table below:
|
Subject
|
Day before
|
Prior to film
|
After film
|
Day after
|
|
A
|
14
|
15
|
18
|
17
|
|
B
|
10
|
13
|
19
|
17
|
|
C
|
15
|
15
|
18
|
18
|
|
D
|
13
|
16
|
20
|
18
|
|
E
|
7
|
9
|
15
|
16
|
|
|
|
|
|
|
State the null and alternative hypotheses and perform the appropriate ANOVA on these data to determine if there is a difference in attitude over time at the .01 level.