Package: irtQ
Type: Package
Title: Unidimensional Item Response Theory Modeling
Version: 1.4.0
Date: 2026-10-16
Description: Fits unidimensional item response theory (IRT) models to
        test data that include dichotomous and polytomous items,
        calibrates pretest items with fixed item and fixed ability
        parameter calibration, performs multiple-group calibration,
        estimates the abilities of examinees, and evaluates model-data
        fit at the item level. It also provides tools for detecting
        differential item functioning and item parameter drift, for
        computing classification accuracy and consistency, and for
        evaluating and simulating multistage-adaptive test panels,
        together with classical test theory functions for item- and
        test-level statistics (e.g., item difficulty, item-total
        correlation, and coefficient alpha) and for scoring
        selected-response item data. The bring.flexmirt() and
        write.flexmirt() functions were written by modifying the
        read.flexmirt() function (Pritikin & Falk (2020)
        <doi:10.1177/0146621620929431>). The bring.bilog() and
        bring.parscale() functions were written by modifying the
        read.bilog() and read.parscale() functions, respectively (Weeks
        (2010) <doi:10.18637/jss.v035.i12>). The bisection() function
        was written by modifying the bisection() function (Howard
        (2017, ISBN:9780367657918)). The code of the inverse test
        characteristic curve scoring in the est_score() function was
        written by modifying the irt.eq.tse() function (Gonzalez (2014)
        <doi:10.18637/jss.v059.i07>). In est_score() function, the code
        of weighted likelihood estimation method was written by
        referring to the Pi(), Ji(), and Ii() functions of the 'catR'
        package (Magis & Barrada (2017) <doi:10.18637/jss.v076.c01>).
Depends: R (>= 4.5)
License: GPL (>= 2)
Encoding: UTF-8
LazyData: true
Imports: stats, statmod, utils, tibble, dplyr, purrr, tidyr, rlang,
        reshape2, janitor, ggplot2, gridExtra, parallel, Matrix, Rfast
Authors@R: c(person("Hwanggyu", "Lim", email="hglim83@gmail.com", role=c("aut", "cre")), 
    person("Craig S.", "Wells", email="cswells@educ.umass.edu", role="ctb"), 
    person("James", "Howard", email="jh@jameshoward.us", role="ctb"),
    person("Joshua", "Pritikin", email="jpritikin@pobox.com", role="ctb"), 
    person("Jonathan P", "Weeks", email="weeksjp@gmail.com", role="ctb"), 
    person("Jorge", "Gonzalez", email="jgonzale@mat.puc.cl", role="ctb"), 
    person("David", "Magis", email="david.magis@uliege.be", role="ctb") 
    ) 
Suggests: knitr, rmarkdown, testthat (>= 3.0.0), pkgdown, RhpcBLASctl,
        mirt
VignetteBuilder: knitr
Config/testthat/edition: 3
Roxygen: list(markdown = TRUE)
URL: https://hwangQ.github.io/irtQ/, https://github.com/hwangQ/irtQ
BugReports: https://github.com/hwangQ/irtQ/issues
Config/roxygen2/version: 8.0.0
Config/pak/sysreqs: cmake libicu-dev
Repository: https://hwangq.r-universe.dev
Date/Publication: 2026-10-24 05:14:20 UTC
RemoteUrl: https://github.com/hwangq/irtq
RemoteRef: HEAD
RemoteSha: 5ad30cd2aa3a7e6a74964df3162e70b0352e7ebc
NeedsCompilation: no
Packaged: 2026-10-24 06:12:56 UTC; root
Author: Hwanggyu Lim [aut, cre],
  Craig S. Wells [ctb],
  James Howard [ctb],
  Joshua Pritikin [ctb],
  Jonathan P Weeks [ctb],
  Jorge Gonzalez [ctb],
  David Magis [ctb]
Maintainer: Hwanggyu Lim <hglim83@gmail.com>