مؤلف: Pedro M. Valero-Mora

The late FORREST W. YOUNG, Ph D, was Professor Emeritus of Quantitative Psychology at The University of North Carolina at Chapel Hill. As a result of a ten-year research project, Dr. Young and his students created Vi Sta: The Visual Statistics System. He acted as a professional consultant for the SAS Institute, Inc., Statistical Sciences, Inc., and Bell Telephone Laboratories. He authored three books and numerous journal articles. He received his Ph D in psychometrics from the University of Southern California, Los Angeles. PEDRO M. VALERO-MORA, Ph D, is Professor of Data Processing at the University of Valencia in Spain. He is the author of several research papers. He received his Ph D in methodology in the behavioral sciences from the University of Valencia in Spain. MICHAEL FRIENDLY, Ph D, is Professor in the Department of Psychology at York University in Toronto, Ontario, Canada. He received his Ph D in psychometrics and cognitive psychology from Princeton University. He is the author of two books and numerous research papers.