This exercise requires mirt for estimating multidimensional IRT models in Exercises The data are available as data(WIRS,package="ltm"). each item with only one latent trait, although multidimensional IRT . The interface is shipped with the package by default, and can be. R package. The mirt package was created for estimating multidimensional item response theory parameters for exploratory and confirmatory. In mirt: Multidimensional Item Response Theory View source: R/itemplot.R mirt: A Multidimensional Item Response Theory Package for the R Environment. estimated with the mirt (Chalmers, ) package. In general .. package? 1) Multidimensional IRT functions in R offered limited features, were. Full-Information Item Factor Analysis (Multidimensional Item Response Chalmers, R., P. (). mirt: A Multidimensional Item Response Theory Package for. A class of Item Response Theory (IRT) models for binary and ordinal polytomous items is illustrated and an R package for dealing with these models, named. Analysis of dichotomous and polytomous response data using unidimensional and multidimensional latent trait models under the Item Response Theory. January 29, Version Type Package. Title Multidimensional Item Response Theory. Description Analysis of dichotomous and polytomous response.