Effect size and power in assessing moderating effects of categorical variables using multiple regression: A 30-year review
Abstract
The authors conducted a 30-year review (1969-1998) of the size of moderating effects of categorical variables as assessed using multiple regression. The median observed effect size (f2) is only .002, but 72% of the moderator tests reviewed had power of .80 or greater to detect a targeted effect conventionally defined as small. Results suggest the need to minimize the influence of artifacts that produce a downward bias in the observed effect size and put into question the use of conventional definitions of moderating effect sizes. As long as an effect has a meaningful impact, the authors advise researchers to conduct a power analysis and plan future research designs on the basis of smaller and more realistic targeted effect sizes.
Publication Title
Journal of Applied Psychology
Recommended Citation
Aguinis, H., Beaty, J., Boik, R., & Pierce, C. (2005). Effect size and power in assessing moderating effects of categorical variables using multiple regression: A 30-year review. Journal of Applied Psychology, 90 (1), 94-107. https://doi.org/10.1037/0021-9010.90.1.94
