Package: irtplay
Type: Package
Title: Evaluation of Model-Data Fit in Item Response Theory (IRT) and
        Useful Functions Related to IRT
Version: 1.2.0
Description: Examine the IRT model-data fit on item-level 
    in different ways as well as provide useful functions related to unidimensional 
    item response theory (IRT). In terms of assessing the IRT model-data fit, one of 
    distinguished features of this package is that it gives not only well-known item 
    fit statistics (e.g., chi-square (X2), likelihood ratio chi-square (G2), infit and oufit statistics 
    (Ames & Penfield (2015) <doi:10.1111/emip.12067>)) but also graphical 
    displays to look at residuals between between the observed data and model-based 
    predictions (Hambleton, Swaminathan, & Rogers (1991, ISBN:9780803936478)). 
    More evaluation methods will be included in the future updated version.  
    In addition to the evaluation of IRT model-data fit, there are several 
    useful functions such as estimating proficiency parameters, calibrating item parameters 
    given the fixed effects (aka. ability values) (Baker & Kim (2004, ISBN:9780824758257)),
    computing asymptotic variance-covariance matrices of item parameter estimates 
    (Li & Lissitz (2004) <doi:10.1111/j.1745-3984.2004.tb01109.x>), importing item and/or 
    ability parameters from popular IRT software, generating simulated data, computing 
    the conditional distribution of observed scores using the Lord-Wingersky recursion 
    formula (Lord & Wingersky (1984) <doi:10.1207/s15324818ame1002_1>), 
    computing the loglikelihood of individual items, computing item and test 
    information functions, computing item and test characteristic curve functions, 
    and plotting item and test characteristic curves and item and test information functions.
Depends: R (>= 3.4)
License: GPL (>= 2)
Encoding: UTF-8
LazyData: true
Imports: stats, statmod, utils, reshape2, dplyr, tidyr, purrr, ggplot2,
        rlang, gridExtra, parallel, pbapply,
Authors@R: c(person("Hwanggyu", "Lim", email="hglim83@gmail.com", role=c("aut", "cre")),
    person("Craig S.", "Wells", email="cswells@educ.umass.edu ", rol="ctb")
    ) 
RoxygenNote: 6.1.1
Suggests: mirt
NeedsCompilation: no
Packaged: 2019-10-17 01:46:20 UTC; kijja
Author: Hwanggyu Lim [aut, cre],
  Craig S. Wells [ctb]
Maintainer: Hwanggyu Lim <hglim83@gmail.com>
Repository: CRAN
Date/Publication: 2019-10-17 05:00:02 UTC
Built: R 3.5.3; ; 2019-11-14 16:32:58 UTC; windows
