Package: hIRT Type: Package Title: Hierarchical Item Response Theory Models Version: 0.4.0 Authors@R: person("Xiang", "Zhou", email = "xiang_zhou@fas.harvard.edu", role = c("aut", "cre")) Description: 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. See Zhou (2019) for details. Depends: R (>= 3.4.0), stats Imports: rms (>= 5.1-1), ltm (>= 1.1-1), Matrix (>= 1.2-10) Suggests: ggplot2 License: GPL (>= 3) Encoding: UTF-8 LazyData: true RoxygenNote: 7.3.3 URL: https://github.com/xiangzhou09/hIRT BugReports: https://github.com/xiangzhou09/hIRT/issues Config/pak/sysreqs: cmake make libicu-dev libuv1-dev Repository: https://xiangzhou09.r-universe.dev Date/Publication: 2026-09-28 14:06:06 UTC RemoteUrl: https://github.com/xiangzhou09/hirt RemoteRef: HEAD RemoteSha: c61f49acde5263f32b7156f923c572144e084e79 NeedsCompilation: no Packaged: 2026-09-29 16:53:27 UTC; root Author: Xiang Zhou [aut, cre] Maintainer: Xiang Zhou