The number of degrees of freedom associated with the t-test, when the data are gathered from a matched pairs experiment with 10 pairs, is:
A) 10
B) 20
C) 9
D) 18
E) 11

Question

Quizplus · Accepted Answer

In a matched pairs experiment, each pair contributes one degree of freedom. Since there are 10 pairs, there are a total of 10 degrees of freedom. However, for the t-test, we need to subtract one degree of freedom because we are estimating the population mean difference using the sample mean difference. Therefore, the number of degrees of freedom for the t-test is (10-1), which is 9.

The Number of Degrees of Freedom Associated with the T-Test