Jerry R. Thomas, EdD, is professor and chair of the department of health and human performance at Iowa State University. Besides writing the previous editions of this book, Thomas has authored more than 200 publications, 87 of which are refereed, and made numerous contributions in research methods. In 1999 Thomas was named the C.H. McCloy Lecturer, based on his career research production. He has also served as editor in chief of Research Quarterly for Exercise and Sport and as a reviewer for most major research journals in kinesiology and numerous journals in psychology. He has served as president of the American Academy of Kinesiology and Physical Education, the AAHPERD Research Consortium, and the North American Society for Psychology of Sport and Physical Activity. He was named an AAHPERD Alliance Scholar in 1990 and NASPSPA Distinguished Scholar in 2003, based on lifetime achievement in research.Jack K. Nelson, EdD, is professor emeritus in the department of kinesiology at Louisiana State University. Nelson conducted and published research and taught research methods for 35 years. He has advised more than 50 doctoral dissertations and more than 50 master’s theses. In addition, he has more than 80 publications and has served as editor of research publications. A fellow in the Research Consortium, he has been a member of AAHPERD, the American Educational Research Association, and the American College of Sports Medicine. He has also served as president of the Association for Research, Administration, Professional Councils and Societies (now the American Association for Active Lifestyles and Fitness, or AAALF) and as vice president of AAHPERD.Stephen Silverman, EdD, has taught and written about research methods for over 20 years. He is a professor of education at Teachers College, Columbia University, and he has conducted research on teaching in physical education focusing on how children learn motor skills and develop attitudes. He has published more than 50 research articles in addition to many books and book chapters. Silverman is a fellow of both the American Academy of Kinesiology and Physical Education and the American Alliance for Health, Physical Education, Recreation and Dance (AAHPERD) Research Consortium. A former coeditor of the Journal of Teaching in Physical Education and current editor in chief of the Research Quarterly for Exercise and Sport, Silverman was an American Educational Research Association Physical Education Scholar Lecturer, a Research Consortium Scholar Lecturer, and Weiss Lecturer for AAHPERD.