Glossary
Moderation
What is Moderation?
Moderation occurs when the relationship between two variables differs across levels of another variable. A moderator describes when, where, or for whom an association or treatment effect varies.
Interpretation
Baron and Kenny’s original distinction separates moderation from mediation: variation in an effect differs from an intermediate pathway producing it. Moderators can be measured characteristics or manipulated conditions.
Example and limits
A hypothetical training study might ask whether the difference between training and control varies with prior experience. The interaction must be assessed directly; a significant result in one subgroup and a nonsignificant result in another do not by themselves establish a difference between subgroups.