Welcome to my personal website.
I am a full professor of methodology and statistics at the Institute of Psychology of Leiden University. The dice you see at the left is often used in classical statistical textbooks to explain random variables and probability. The dice also represents a choice mechanism with a categorical outcome, one of my main research interests.
In psychology the dice is often not fair: some sides are heavier than others, or stated differently, some options have a larger probability. The main task then is to estimate these probabilities and to link them to known characteristics of the participants under study.

Mark de Rooij
Professor of Methodology and Statistics in Psychological Research
Methodology and Statistics Unit
Institute of Psychology
Leiden University
Rooijm at