In a matrix representing the structure of a factorial design,the differences between the overall column means define
A)the main effect for one factor.
B)the interaction between the factors.
C)the main effect and the interaction between the factors.
D)nothing.

Question

Quizplus · Accepted Answer

The differences between the overall column means represent the main effect for each factor. This is because the overall column means represent the average response across all levels of the other factor(s), so any differences between these means can be attributed solely to the level of the factor being considered. The overall row means, on the other hand, represent the grand mean, which is the average response across all factor levels, so differences between these means represent the interaction between the factors.

In a Matrix Representing the Structure of a Factorial Design,the