catR: Generation of IRT Response Patterns under Computerized Adaptive Testing

Provides routines for the generation of response patterns under unidimensional dichotomous and polytomous computerized adaptive testing (CAT) framework. It holds many standard functions to estimate ability, select the first item(s) to administer and optimally select the next item, as well as several stopping rules. Options to control for item exposure and content balancing are also available (Magis and Raiche (2012) <doi:10.18637/jss.v048.i08>).

Install the latest version of this package by entering the following in R:
AuthorDavid Magis (U Liege, Belgium), Gilles Raiche (UQAM, Canada), Juan Ramon Barrada (U Zaragoza, Spain)
Date of publication2017-01-08 12:02:08
MaintainerDavid Magis <>
LicenseGPL (>= 2)

View on CRAN

Man pages

breakBank: Breaking the item bank in item parameters and group...

checkStopRule: Checking whether the stopping rule is satisfied

eapEst: EAP ability estimation (dichotomous and polytomous IRT...

eapSem: Standard error of EAP ability estimation (dichotomous and...

EPV: Expected Posterior Variance (EPV)

GDI: Global-discrimination index (GDI) and posterior...

genDichoMatrix: Item bank generation (dichotomous models)

genPattern: Random generation of item response patterns under dichotomous...

genPolyMatrix: Item bank generation (polytomous models)

Ii: Item information functions, first and second derivatives...

integrate.catR: Numerical integration by linear interpolation (for catR...

Ji: Function J(theta) for weighted likelihood estimation...

KL: Kullback-Leibler (KL) and posterior Kullback-Leibler (KLP)...

MEI: (Maximum) Expected Information (MEI)

MWI: Maximum likelihood weighted information (MLWI) and maximum...

nextItem: Selection of the next item

OIi: Observed information function (dichotomous and polytomous...

Pi: Item response probabilities, first, second and third...

randomCAT: Random generation of adaptive tests (dichotomous and...

semTheta: Standard error of ability estimation (dichotomous and...

simulateRespondents: Simulation of multiple examinees of adaptive tests

startItems: Selection of the first items

tcals: Items parameters of the TCALS 1998 data set and subgroups of...

test.cbList: Testing the format of the list for content balancing under...

testList: Testing the format of the input lists

thetaEst: Ability estimation (dichotomous and polytomous models)


breakBank Man page
checkStopRule Man page
eapEst Man page
eapSem Man page
EPV Man page
GDI Man page
genDichoMatrix Man page
genPattern Man page
genPolyMatrix Man page
Ii Man page
integrate.catR Man page
Ji Man page
KL Man page
MEI Man page
MWI Man page
nextItem Man page
OIi Man page
Pi Man page Man page
plot.catResult Man page Man page
print.catResult Man page
randomCAT Man page
semTheta Man page
simulateRespondents Man page
startItems Man page
tcals Man page
test.cbList Man page
testList Man page
thetaEst Man page

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