Herman Ader was born on the 20th of May, 1940, in Amsterdam. He studied at the University of Amsterdam and holds a bacholor s degrees in general psychology and in social science methods; his masters degree is in Numerical Mathematics.He worked at VU University from 1971 until 2005, first at the Faculty of Psychology, and from 1993 2005 at the Department of Clinical Epidemiology and Biostatistics of the VU University medical center.Herman J. Ader has been an advisor on methodological and statistical matters for many years, lately at the Trimbos Institute for social science research in Utrecht,