Kristopher J. Preacher, Ph.D. is a Professor in the Quantitative Methods program at Vanderbilt University. His research concerns the use (and combination) of structural equation modeling and multilevel modeling to model correlational and longitudinal data. Other interests include developing techniques to test mediation and moderation hypotheses, bridging the gap between substantive theory and statistical practice, and studying model evaluation and model selection in the application of multivariate methods to social science questions. He serves on the editorial boards of Psychological Methods, Multivariate Behavioral Research, and Communication Methods and Measures.