Analysis of dichotomous and polytomous response data
using latent trait models under the Item Response Theory
paradigm. Exploratory models can be estimated via
quadrature or stochastic methods, a generalized
confirmatory bi-factor analysis is included, and
confirmatory models can be fit with a Metropolis-Hastings
Robbins-Monro algorithm which can include polynomial or
product constructed latent traits. Multiple group
analysis and mixed effects designs may be performed for
unidimensional or multidimensional item response models
for detecting differential item functioning and modelling
item and person covariates. Users interested in the most recent version of this
package can visit
https://github.com/philchalmers/mirt and follow
the instructions for installing the package from source.