In performing a two-way ANOVA for a two-factor factorial experiment under which of the following circumstances would we test the significance of the main effects?
A)Substantial interaction exists between factors 1 and 2.
B)Little or no interaction exists between factors 1 and 2.
C)The factor 1 sum of squares equals the factor 2 sum of squares.
D)We reject the null hypothesis of no interaction.
E)The error sum of squares is equal to the interaction sum of squares.

Question

Quizplus · Accepted Answer

When there is little or no interaction between the factors, it is appropriate to test the significance of the main effects. This is because when there is interaction, the main effects may not be meaningful and their significance cannot be easily interpreted. Therefore, the best choice is B.

In Performing a Two-Way ANOVA for a Two-Factor Factorial Experiment