Investigation of adolescents' developmental stages in deductive reasoning: An application of a specialized confirmatory mixture IRT approach.

In this paper, we propose a specialized confirmatory mixture IRT model to analyze complex cognitive assessment data that is designed to evaluate adolescents' developmental stages in deductive reasoning. The model is specified for the following purposes: (1) to measure multiple deductive reasoning traits, (2) to identify adolescents' differential developmental stages based on their ability levels in the multiple dimensions, (3) to quantify the differences in dimension-specific performance between developmental stages, and (4) to examine the difficulty levels of test design factors. A Bayesian estimation of the model is described. The overall goodness-of-fit of the model is assessed as well as its parameter recovery to validate the application of the model to the data.