Question

a physical therapy researcher was interested in determining the impact of two different exercises. the investigator suspected that the two exercises produced a different level of activity in the muscle. each of 16 subjects performed both exercise 1 and exercise 2, and the results are shown (for each subject, the order of the exercises was randomly assigned and sufficient rest time was provided between the two exercises).
subject exercise 1 exercise 2
1 4.53 5.00
2 6.72 7.12
3 3.79 4.21
4 5.82 5.78
5 5.00 6.29
6 4.00 5.13
7 2.19 3.95
8 7.34 7.20
9 9.12 8.95
10 1.79 4.12
11 8.10 9.68
12 7.52 8.25
13 6.25 7.15
14 6.60 7.98
15 7.00 7.10
16 6.23 6.00
which of the following is the most appropriate statistical test to use to determine the impact of the two difference exercises?
a. two - sample t - test
b. matched pairs t - test
c. anova
d. chi - squared test for independence
e. inference for regression

Explanation:

The same 16 subjects perform both exercises. This creates a natural pairing for each subject. A matched - pairs t - test is used when we have paired data (in this case, the results of two exercises for the same individuals) to test for a difference between the two related samples. A two - sample t - test is for independent samples. ANOVA is used for comparing means of more than two groups. The chi - squared test for independence is for categorical data. Inference for regression is for predicting a response variable based on an explanatory variable.

Answer:

B. Matched pairs t - test