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Analysis of Differential Item Functioning (DIF) for dichotomous and polytomous items using an iterative hybrid of ordinal logistic regression and item response theory (IRT).
Package details 


Author  Seung W. Choi, with contributions from Laura E. Gibbons and Paul K. Crane 
Maintainer  Seung W. Choi <choi.phd@gmail.com> 
License  GPL (>= 2) 
Version  0.33 
Package repository  View on CRAN 
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