Package: robustDIF
Type: Package
Title: Differential Item Functioning Using Robust Scaling
Version: 0.2.0
Authors@R: 
  c(
    person(given = "Peter",
           family = "Halpin",
           role = c("aut", "cre"),
           email = "peter.halpin@unc.edu"),
    person(given = "Kyle",
           family = "Nickodem",
           role = "ctb"),
    person(given = "James",
           family = "Eagle",
           role = "ctb")
  )
Description: Provides tools for testing differential item functioning (DIF) and differential test functioning (DTF) in two-group item response theory models. The package estimates robust scaling parameters via iteratively reweighted least squares with Tukey's bisquare loss, and supports Wald-type tests of item-level and test-level differences from robust scaling parameters. Inputs can be supplied directly from model parameter/covariance objects or extracted from fitted 'mirt' and 'lavaan' models. Methods are described in Halpin (2022) <doi:10.48550/arXiv.2207.04598>.
License: GPL (>= 3)
Encoding: UTF-8
LazyData: true
Depends: R(>= 3.5.0), Matrix
Imports: mirt, lavaan
Suggests: testthat (>= 3.0.0)
Config/testthat/edition: 3
RoxygenNote: 7.3.3
NeedsCompilation: no
Packaged: 2026-04-16 13:50:06 UTC; peterhalpin
Author: Peter Halpin [aut, cre],
  Kyle Nickodem [ctb],
  James Eagle [ctb]
Maintainer: Peter Halpin <peter.halpin@unc.edu>
Repository: CRAN
Date/Publication: 2026-04-21 18:42:07 UTC
Built: R 4.5.2; ; 2026-04-21 23:05:56 UTC; unix
