ESTIMATING THE POWER TO DETECT DICHOTOMOUS MODERATORS WITH MODERATED MULTIPLE-REGRESSION

A QuickBASIC program for estimating the statistical power to detect the effects of dichotomous moderator variables using moderated multiple regression (MMR) is available. The program runs on IBM and IBM-compatible personal computers and estimates power based on specific values for (a) total sample size, (b) sample sizes across the two categories of the hypothesized moderator, and (c) correlation coefficients between predictor and criterion scores for each of the two moderator-based subgroups. The compiled run time and source code versions of the program can be obtained from the first author.