I'm an assistant professor and teach at the Psychological and Mathematical Institutes of Leiden University. My research is about statistics, machine learning and psychological assessment.

• I work on decision-tree methods a lot, because they are relatively easy to understand by non-statisticians. Here is a short interview about my work on trees (in Dutch).

• I develop open-source software packages for the programming environment R (see left or GitHub).

• My work has been published in journals like Psychological Methods, the Journal of Statistical Software, Information Fusion and World Psychiatry (see menu on the left or Google Scholar).

• As Mary-Jo and the Support Vector Machines, I make music videos about statistical methods (see menu on the left or YouTube).