# Chapter 7 Fundamentals of Moderation Analysis

On page 220, Hayes stated:

The effect of $$X$$ on some variable $$Y$$ is moderated by $$W$$ if its size, sign, or strength depends on or can be predicted by $$W$$. In that case, $$W$$ is said to be a moderator of $$X$$’s effect on $$Y$$, or that $$W$$ and $$X$$ interact in their influence on $$Y$$.