irtQ: Unidimensional Item Response Theory Modeling
Fit unidimensional item response theory (IRT) models to test
    data, which includes both dichotomous and polytomous items, calibrate 
    pretest item parameters, estimate examinees' abilities, and examine 
    the IRT model-data fit on item-level in different ways as well as provide 
    useful functions related to IRT analyses such as IRT model-data fit 
    evaluation and differential item functioning analysis. 
    The bring.flexmirt() and write.flexmirt() functions were written by modifying 
    the read.flexmirt() function (Pritikin & Falk (2022) <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 
    (González (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>).
| Version: | 1.0.0 | 
| Depends: | R (≥ 4.3) | 
| Imports: | stats, statmod, utils, tibble, dplyr, purrr, tidyr, rlang, reshape2, janitor, ggplot2, gridExtra, parallel, Matrix, Rfast, mirt | 
| Published: | 2025-07-17 | 
| DOI: | 10.32614/CRAN.package.irtQ | 
| Author: | Hwanggyu Lim [aut, cre],
  Craig S. Wells [ctb],
  James Howard [ctb],
  Joshua Pritikin [ctb],
  Jonathan P Weeks [ctb],
  Jorge González [ctb],
  David Magis [ctb] | 
| Maintainer: | Hwanggyu Lim  <hglim83 at gmail.com> | 
| License: | GPL-2 | GPL-3 [expanded from: GPL (≥ 2)] | 
| NeedsCompilation: | no | 
| Materials: | README, NEWS | 
| CRAN checks: | irtQ results | 
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