Chapter 10, Problem 9PT

To determine

To find: the most suitable inference procedure for answering the original research question.

Answer to Problem 9PT

Two-sample z interval for a proportion difference $P_1-P_2$

Explanation of Solution

Generally

One proportion: for one-sample z test/interval

Two proportions: for two-sample z test/interval

One mean: for one sample t test/interval

Two means: for two-sample t test/ interval or paired t test/interval

Use a test if want to test for a difference, equality, decrease or increase, use an interval if want to calculate an interval in which the true value comes.

For two-sample z interval for a proportion difference is $P_1-P_2$

Because here interested in the calculation of the difference of the proportions.

Hence, the correct option is (b)