Abstract:

Explanatory item response theory models (EIRTM) refer to a family of item response theory (IRT) models that are constructed based on the generalized linear mixed models and nonlinear mixed models. EIRTM can be utilized to address various measurement problems by incorporating predictors into IRT models. First, the relevant concepts and parameter estimation methods of EIRTM are introduced in this paper, followed by the procedures regarding how to use EIRTM to account for the item position effect, test mode effect, differential item functioning, local person dependence, and local item dependence. Next, an example is provided to illustrate the use of EIRTM. Finally, the shortcomings and potential applications of EIRTM are discussed.

Key words: explanatory item response theory, generalized linear mixed models, nonlinear mixed models, measurement invariance, explanatory measurement