Niels Veldhuijzen

Psychometrician/Senior researcher

National Institute for Educational Measurement (Cito)

                   Measurement & Research Department (POK)

                   P.O. Box 1034

                   NL-6801 MG  Arnhem, The Netherlands

                   Tel.: +31263521416; fax: +31263521356

E-mail: (work), (home)

Home site:

Full-time psychometrician, using IRT mostly (the OPLM  [One Parameter Logistic Model ] of Eggen & Verhelst is the "home" model at Cito; my colleague Norman Verhelst and I are modernizing and 'Window-izing' the package), partly in the Dutch National Assessment Program for primary schools. As I think it good practice to look at data from different perspectives before delving into IRT, I use several data analytic tools (Gifi things, Wilks & Gnanadesikan) as preprocessors.

 My interest in scaling started when at Leiden University in the "boom era" of nonmetric MDS; although  I was not part of the Data Theory group (Gifi),  I was thoroughly influenced by it. As all serious scaling software at the time was written in Fortran, I became an ardent Fortran user, and still am. I think Fortran is very good for (heavy)numerical computations; especially the new Fortran90/95 form . Current production includes Andrews' Hi-dimensional Scheme, and Homogeneity Analysis.