An artifactual main effect may occur in a two-factor design because.
A)there is unusually extensive error variation
B)of the pattern of a statistically significant interaction
C)of having too few degrees of freedom for the error term
D)the two main effects are not equal to each other

Question

Quizplus · Accepted Answer

An artifactual main effect can occur due to the pattern of a statistically significant interaction. This means that the apparent effect of one factor at one level of the other factor may not hold at a different level of the other factor, leading to a misleading interpretation of main effects when there is significant interaction.

An Artifactual Main Effect May Occur in a Two-Factor Design