In the two-factor ANOVA where a is the number of factor A levels,b is the number of factor B levels,and r is the number of replicates,the number of degrees of freedom for interaction is:
A)(a − 1)(b − 1)
B)abr − 1
C)(a − 1)(r − 1)
D)n − ab

Question

Quizplus · Accepted Answer

The number of degrees of freedom for interaction is calculated by multiplying the degrees of freedom for factor A, B, and the replicates (r) and then subtracting the total degrees of freedom (n - 1). The degrees of freedom for factor A and B are both (a-1) and (b-1), respectively, so the total degrees of freedom for interaction is (a-1)(b-1)r, which matches with option A.

In the Two-Factor ANOVA Where a Is the Number of Factor