Person Fit

Several person-fit statistics (PFSs) are offered. These statistics allow assessing whether individual response patterns to tests or questionnaires are (im)plausible given the other respondents in the sample or given a specified item response theory model. Some PFSs apply to dichotomous data, such as the likelihood-based PFSs (lz, lz*) and the group-based PFSs (personal biserial correlation, caution index, (normed) number of Guttman errors, agreement/disagreement/dependability statistics, U3, ZU3, NCI, Ht). PFSs suitable to polytomous data include extensions of lz, U3, and (normed) number of Guttman errors.


Reference manual

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1.4.3 by Jorge N. Tendeiro, 6 months ago

Browse source code at

Authors: Jorge N. Tendeiro

Documentation:   PDF Manual  

GPL (>= 2) license

Imports stats, graphics, fda, Hmisc, irtoys, MASS, Matrix

Depends on ltm, mirt

See at CRAN