Computational Strategies and Estimation Performance With Bayesian Semiparametric Item Response Theory Models. (April 2023)

• Record Type: Journal Article
• Authors: Paganin, Sally; Paciorek, Christopher J.; Wehrhahn, Claudia; Rodríguez, Abel; Rabe-Hesketh, Sophia; de Valpine, Perry
• Is Part Of: Journal of educational and behavioral statistics. Volume 48:Number 2(2023)
• Page Start: 147
• Page End: 188
• Publication Date: 2023-04
• Subjects: binary IRT models -- Dirichlet process mixture -- MCMC strategies -- NIMBLE; Educational statistics -- Periodicals; Social sciences -- Statistical methods -- Periodicals; 370.2
• DOI: 10.3102/10769986221136105
• Languages: English
• ISSNs: 1076-9986

Abstract

Item response theory (IRT) models typically rely on a normality assumption for subject-specific latent traits, which is often unrealistic in practice. Semiparametric extensions based on Dirichlet process mixtures (DPMs) offer a more flexible representation of the unknown distribution of the latent trait. However, the use of such models in the IRT literature has been extremely limited, in good part because of the lack of comprehensive studies and accessible software tools. This article provides guidance for practitioners on semiparametric IRT models and their implementation. In particular, we rely on NIMBLE, a flexible software system for hierarchical models that enables the use of DPMs. We highlight efficient sampling strategies for model estimation and compare inferential results under parametric and semiparametric models.