An independent-measures study uses n = 15 participants in each group to compare two treatment conditions. What is the df value for the t statistic for this study? a. 14 b. 15 c. 28 d. 29

c. 28

Step-by-step explanation:

The degrees of freedom for a t-statistics is given by the following formula:

df = (sample size - 1) * number of experiments.

In this problem, we have that:

15 participants, so the sample size is 15.

Two treatment conditions, so the number of experiments is 2.

So

df = (15 - 1) * 2 = 28

So the correct answer is:

c. 28