How to Think Straight About Psychometrics: Improving Measurement by Identifying its Assumptions

Abstract

The aim of the current study is to present three assumptions common to psychometric theory and psychometric practice, and to show how alternatives to traditional psychometrical approaches can be used to improve psychological measurement. These alternatives are developed by adapting each of these three assumptions. The assumption of structural validity relates to the implementation of mathematical models. The process assumption which is underlying process generates the observed data. The construct assumption implies that the observed data on its own do not constitute a measurement, but the latent variable that originates the observed data. Nonparametric item response modeling and cognitive psychometric modeling are presented as alternatives for relaxing the first two assumptions, respectively. Network psychometrics is the alternative for relaxing the third assumption. Final remarks sum up the most important conclusions of the study.