Moderating Effects with Seemingly Uncorrelated Variables
Jeremy Taylor |
Wednesday, July 13, 2011 at 7:00AM I received a great question this week, as a submission to my Ask the Stats Make Me Cry Guy page, which asked: In order for a moderating relationship to exist, do the predictor IV and dependent variable need to be significantly correlated?". This is a question that I am asked a lot, partly because of the common confusion between mediators and moderators and the commonly held belief that an IV and DV should be related for mediation to be present (see my video blog on Mediators, Moderators, and Supressors for more info on this topic). However, moderators are a completely different story. In fact, a simple correlation between two variables can be very misleading, if one relies on it as an indicator of potential moderating effects and/or as an indicator that moderating effects should be tested.
