Hierarchical Item Response Theory Models
Parameter Estimates from Hierarchical IRT Models.
Fitting Hierarchical Graded Response Models (for Ordinal Responses)
Hierarchical Graded Response Models with Known Item Parameters
Fitting Hierarchical Latent Trait Models (for Binary Responses).
Hierarchical Latent Trait Models with Known Item Parameters.
Estimates of Latent Preferences/Abilities
Printing an object of class hIRT
Summarizing Hierarchical Item Response Theory Models
Implementation of a class of hierarchical item response theory (IRT) models where both the mean and the variance of latent preferences (ability parameters) may depend on observed covariates. The current implementation includes both the two-parameter latent trait model for binary data and the graded response model for ordinal data. Both are fitted via the Expectation-Maximization (EM) algorithm. Asymptotic standard errors are derived from the observed information matrix.