Gregory R. Hancock is Professor in the Department of Measurement, Statistics and Evaluation at the University of Maryland, College Park, and Director of the Center for Integrated Latent Variable Research (CILVR).  His research has appeared in such journals as Psychometrika, Multivariate Behavioral Research, Structural Equation Modeling: A Multidisciplinary Journal, British Journal of Mathematical and Statistical Psychology, Psychological Bulletin, Journal of Educational and Behavioral Statistics, Educational and Psychological Measurement, Review of Educational Research, and Communications in Statistics: Simulation and Computation.  He also co-edited with Ralph Mueller the volume Structural Equation Modeling: A Second Course, and with Karen M. Samuelsen the volume Advances in Latent Variable Mixture Models. He is past chair of the SEM special interest group of the American Educational Research Association, and serves on the editorial board of a number of methodological and applied journals, including Structural Equation Modeling: A Multidisciplinary Journal.  Dr. Hancock holds a Ph.D. from the University of Washington.  He can be reached via email at: ghancock@umd.edu.