In the three-factor fixed effects model, assume that there are 4 levels of factor A, 2 levels of factor B, 4 levels of factor C, and 3 observations for each combination of levels of the three factors. Then, the number of degrees of freedom for the three-factor interaction sum of squares (SSABC) is
A) 32
B) 10
C) 9
D) 12
E) 13

Question

Quizplus · Accepted Answer

The degrees of freedom for the three-factor interaction (SSABC) is calculated as (a-1)(b-1)(c-1), where a, b, and c are the number of levels for factors A, B, and C, respectively. Thus, (4-1)(2-1)(4-1) = 3*1*3 = 9.

In the Three-Factor Fixed Effects Model, Assume That There Are