A manufacturer wished to compare the wearing qualities of two different types of automobile tires, A and B, and he had 5 cars available for use in an experiment. To make the comparison, one tire of Type A and one of Type B were mounted on the rear wheels of each of the five automobiles. (For each car, a coin was flipped to decide which tire would be mounted on the left side and which would be mounted on the right.). The automobiles were then operated for a specified number of miles and the amount of wear was recorded for each tire. These measurements appear below:
Automobile Tire A Tire B
1 10.6 10.2
2 9.8 9.4
3 12.3 11.8
4 9.7 9.1
5 8.8 8.3
An appropriate parametric procedure is to be used for testing the null hypothesis that there is no difference in the average wear for the two types of tires. The absolute value of the test statistic calculated from the data is:
12.83
10.72
0.57
9.45
8.35