William has 20 students take a test on two different occasions. What would be the df if he wanted to compare the mean scores from both occasions?
A) 39
B) 38
C) 19
D) 18

Question

Quizplus · Accepted Answer

The degrees of freedom for comparing means from two independent samples is calculated as follows: df = (n1 - 1) + (n2 - 1) = (20 - 1) + (20 - 1) = 19 + 19 = 38. Therefore, the correct answer is C, 19.

William Has 20 Students Take a Test on Two Different