This R-package includes two approaches to perform a score-test for DIF detection based on resampling techniques, and is focused on data from Multi-Stage Adaptive Tests. Currently the functionality is limited to the 1-, 2-, and 3-PL models. Only the DIF in the threshold (b) and slope (a) parameter are tested for. Rather than using the theoretical distribution to obtain the p-value for the score-based test statistic, this distribution is obtained using resampling techniques.
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permutation_sctest
samples permutations of person orders. -
bootstrap_sctest
samples new data based on the estimated (item and person).
The package can be installed using using the devtools
-package:
install.packages("devtools")
devtools::install_github("ddebeer/Rsctest")