Name:________________________
1. Extra credit (meaning the 5 points for this problem will be added to your total, but not to the possible total). Do exercise 8.27 on page 378 by carrying out the Lilliefors test. Trace the graph on page 197. Draw in the bounding curves for sample size n = 12 where you think they should be somewhere between the n = 10 and the n = 20 curves.
2. Do exercise 8.28 on page 378. As a result of exercise 8.27 , it is unreasonable to assume normality for the paired data in this exercise.
3. Do Exercise 9.8 on page 391.
4. A college professor teaches two sections of the same course, each
meeting for 53 minutes. One meets at noon and the other at 2:30 p.m.
At examination time, he gives identical exams to both classes. He
is concerned that the 2:30 section might have higher scores, based on
information received from individuals in the noon section. Assume
these test scores resemble two indepedndent random samples from
normal populations with equal variances.
a). At the .01 level of significance, test the null hypothesis
that the means are the same for both sections versus the alternative
hypothesis that section 2 has higher mean.
b). Find a 99% confidence interval for the difference in the means of
the two sections.
The data:
Section 1: 82, 65, 78, 81, 79, 80, 91, 81, 80, 70, 79, 77
Section 2: 88, 94, 82, 80, 84, 86, 84, 81, 73, 84
5. (Like exercise 9.17 on page 404). Test the assumption of equality of variances for the test scores in problem 4 above. Let alpha = .05 and state the p-value.