In this paper it is demonstrated how statistical inference from multistage test designs can be made based on the conditional likelihood. Special attention is given to parameter estimation, as well as the evaluation of model fit. Two reasons are provided why the fit of simple measurement models...

Warm (in Psychometrika, 54, 427–450, <CitationRef CitationID="CR12">1989</CitationRef>) established the equivalence between the so-called Jeffreys modal and the weighted likelihood estimators of proficiency level with some dichotomous item response models. The purpose of this note is to extend this result to polytomous item response...</citationref>

Surveys are widely used by scholars, companies, and public policymakers to generate invaluable insights. Despite the popularity of surveys, there are several biases that can affect the validity of self-reported data. In his inaugural address, Martijn de Jong discusses how new survey methods can...

An unfolding model for continuous bounded responses is proposed, derived both from a hypothetical interpolation response mechanism and from the hypothesis of two opposite sources of item refusal being collapsed. These two sources of refusal are made explicit in a three-component Dirichlet...