Larry B. Wallnau is Professor Emeritus of Psychology at The College at Brockport, State University of New York. The recipient of grants and awards in both research and teaching, Dr. Wallnau has published numerous research articles primarily on the effect of psychotropic drugs. With Frederick J Gravetter, he has co-authored previous editions of STATISTICS FOR THE BEHAVIORAL SCIENCES, now in its tenth edition, and ESSENTIALS OF STATISTICS FOR THE BEHAVIORAL SCIENCES, now in its ninth edition.