Heart Rate and Exercise Exercise 11.60 presented data (data set EX1160) on the heart...

Heart Rate and Exercise Exercise 11.60 presented data (data set EX1160) on the heart rates for samples of 10 men randomly selected from each of four age groups. Each man walked a treadmill at a fixed grade for a period of 12 minutes, and the increase in heart rate (the difference before and after exercise) was recorded (in beats per minute). The data are shown in the table.

a . Do the data present sufficient evidence to indicate differences in location for at least two of the four age groups? Test using the Kruskal–Wallis H-test with α = .01.

b. Find the approximate p-value for the test in part a.

c. Since the F-test in Exercise 11.60 and the H-test in part a are both tests to detect differences in location of the four heart-rate populations, how do the test results compare? Compare the p-values for the two tests and explain the implications of the comparison.

Reference:

Heart Rate and Exercise An experiment was conducted to examine the effect of age on heart rate when a person is subjected to a specific amount of exercise. Ten male subjects were randomly selected from four age groups: 10–19, 20–39, 40–59, and 60–69. Each subject walked on a treadmill at a fixed grade for a period of 12 minutes, and the increase in heart rate, the difference before and after exercise, was recorded (in beats per minute):

Use an appropriate computer program to answer these questions:

a. Do the data provide sufficient evidence to indicate a difference in mean increase in heart rate among the four age groups? Test by using α = .05.

b. Find a 90% confidence interval for the difference in mean increase in heart rate between age groups 10–19 and 60–69.

c. Find a 90% confidence interval for the mean increase in heart rate for the age group 20–39.

d. Approximately how many people would you need in each group if you wanted to be able to estimate a group mean correct to within two beats per minute with probability equal to .95?