Theodore A. Walls, Ph.D., is Professor of Psychology at the University of Rhode Island. As a research scientist at The Methodology Center at The Pennsylvania State University, Dr. Walls developed methods for the analysis of intensive longitudinal data and convened the international study group whose work led to the publication of this volume. His current work is focused on the development of models reflecting dynamic intraindividual processes. Joseph L. Schafer, Ph.D., is Associate Professor of Statistics and an Investigator at The Methodology Center at The Pennsylvania State University....