Modeling Multidimensional Forced Choice Measures with the Zinnes and Griggs Pairwise Preference Item Response Theory Model.

This research developed a new ideal point-based item response theory (IRT) model for multidimensional forced choice (MFC) measures. We adapted the Zinnes and Griggs (ZG; 1974) IRT model and the multi-unidimensional pairwise preference (MUPP; Stark et al., 2005) model, henceforth referred to as ZG-MUPP. We derived the information function to evaluate the psychometric properties of MFC measures and developed a model parameter estimation algorithm using Markov chain Monte Carlo (MCMC). To evaluate the efficacy of the proposed model, we conducted a simulation study under various experimental conditions such as sample sizes, number of items, and ranges of discrimination and location parameters. The results showed that the model parameters were accurately estimated when the sample size was as low as 500. The empirical results also showed that the scores from the ZG-MUPP model were comparable to those from the MUPP model and the Thurstonian IRT (TIRT) model. Practical implications and limitations are further discussed.