Question: The heart rates of 15 men between the ages of 70 and 95 were measured before and after participating in a three-month exercise program.

Subject Before After After-Before Difference, d

1 88 90 2

2 94 91 -3

3 99 99 0

4 101 98 -3

5 96 97 1

6 91 91 0

7 88 90 2

8 101 95 -6

9 105 100 -5

10 98 100 2

11 96 94 -2

12 98 97 -1

13 87 84 -3

14 88 82 -6

15 91 90 -1

a. Calculate the paired t-test and Wilcoxon Signed Ranks test with a 0.10 significance criterion?

b. Briefly interpret the results of the t-test. What conclusions can you make about the effect of the exercise program on the heart rates of these elderly men?