idmact: Interpreting Differences Between Mean ACT Scores

Interpreting the differences between mean scale scores across various forms of an assessment can be challenging. This difficulty arises from different mappings between raw scores and scale scores, complex mathematical relationships, adjustments based on judgmental procedures, and diverse equating functions applied to different assessment forms. An alternative method involves running simulations to explore the effect of incrementing raw scores on mean scale scores. The 'idmact' package provides an implementation of this approach based on the algorithm detailed in Schiel (1998) <> which was developed to help interpret differences between mean scale scores on the American College Testing (ACT) assessment. The function idmact_subj() within the package offers a framework for running simulations on subject-level scores. In contrast, the idmact_comp() function provides a framework for conducting simulations on composite scores.

Version: 1.0.1
Imports: rlang
Suggests: knitr, rmarkdown, testthat (≥ 3.0.0)
Published: 2023-05-18
DOI: 10.32614/CRAN.package.idmact
Author: Mackson Ncube [aut, cre, cph]
Maintainer: Mackson Ncube <macksonncube.stats at>
License: MIT + file LICENSE
NeedsCompilation: no
Materials: README NEWS
CRAN checks: idmact results


Reference manual: idmact.pdf
Vignettes: Additional-Workflows


Package source: idmact_1.0.1.tar.gz
Windows binaries: r-devel:, r-release:, r-oldrel:
macOS binaries: r-release (arm64): idmact_1.0.1.tgz, r-oldrel (arm64): idmact_1.0.1.tgz, r-release (x86_64): idmact_1.0.1.tgz, r-oldrel (x86_64): idmact_1.0.1.tgz


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