A paired difference experiment produced the following data:

nd = 9 x1 = 150 x2 = 157 xd = -7 sd 2

= 36

a. Determine the values of t for which the null hypothesis m1 - m2 = 0 would be rejected in favor of the alternative hypothesis m1 - m2 6 0. Use a = .10.

b. Conduct the paired difference test described in part a.

Draw the appropriate conclusions.

c. What assumptions are necessary so that the paired difference test will be valid?

d. Find a 90% confidence interval for the mean difference md.

e. Which of the two inferential procedures, the confidence interval of part d or the test of hypothesis of part

b, provides more information about the difference between the population means?