Chapter 10.2, Problem 68E

To determine

To find: the best answer on the basis of given information.

Answer to Problem 68E

  $\text{Paired t test for }{\mu }_d$

Explanation of Solution

Generally

One proportion: check with one-sample z test/ interval

Two proportions or proportion difference: for two-sample z test/interval

One mean: for one-sample t test/interval

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

Two means or mean difference with paired data in the two samples: for paired t test/interval

Using a test when needs to test for a difference, equality, increase or decrease. Using an interval when needs to calculate an interval in which the true value lies.

  $\text{Paired t test for }{\mu }_d$

This is since the two methods are performed to the same random sample

Hence, the correct option is (a)