DFIT1.1 package

Differential Functioning of Items and Tests

ExtractGRMMirt

Extract item discrimination and difficulties and estimate covariance e...

ExtractMirtPars

Extracts the item parameters from a unidimensional mirt model

ExtractRaschMirt

Extract item difficulties and item difficulty variance estimates for R...

Ipr

Item parameter replication

IprMh

Mantel Haenszel for Item parameter replication

Ase1pl

Calculates the asymptotic variance for difficulty parameter estimates ...

Ase2pl

Calculates the asymptotic covariance matrix of item parameter estimate...

Ase3pl

Calculates the asymptotic covariance matrix of item parameter estimate...

AseIrt

Calculates the asymptotic covariance matrices for item parameters acco...

Bound3PlIpr

Takes item parameters from Ipr and forces guessing to lie between 0 an...

Bound4PlIpr

Takes item parameters from Ipr and forces guessing to lie between 0 an...

Calculate1plProb

Calculates the item success probability under the 1PL model.

Calculate2plProb

Calculates the item success probability under the 2PL model.

Calculate3plProb

Calculates the item success probability under the 3PL model.

Calculate4plProb

Calculates the item success probability under the 4PL model.

CalculateGrmExp

Calculates the expected item score under the GRM model.

CalculateItemDifferences

Calculates the differences between two item option characteristic curv...

CalculatePcmExp

Calculates the expected item score under the (G)PCM model.

Cdif

Calculates CDIF index for an item with given item parameters of focal ...

CheckDiscriminations

Identifies items with nonpositive discrimination

CheckGuessings

Identifies items with guessing outside [0, 1]

CheckUpper

Identifies items with upper asymptote outside [0, 1]

CrossedProbabilities

Calculates the crossed probabilities associated with the numerator and...

CutoffIpr

Cut-off points for Ipr generated estimates

DeltaMhIrt

Obtains the ETS Delta measure for Mantel-Haneszel DIF statistic effect...

DFIT

Differential Functioning of Items and Tests framework

Dtf

Calculates DTF index for a set of items with given item parameters of ...

Extract2PLMirt

Extract item discrimination and difficulties and estimate covariance e...

Extract3PLMirt

Extract item discrimination, difficulties, and guessing parameters and...

Extract4PLMirt

Extract item discrimination, difficulties, guessing, and upper asympto...

ExtractGPCMMirt

Extract item discrimination and difficulties and estimate covariance e...

IprNcdif

NCDIF for Item parameter replication

IprSam

Signed Area Measure for Item parameter replication

IprUam

Unsigned Area Measure for Item parameter replication

IrtMh

Calculates the Mantel-Haenszel theoretical parameter when a dichotomou...

Ncdif

Calculates NCDIF index for an item with given item parameters of focal...

PlotNcdif

Plot the item characteristic (expected score) curve for focal and refe...

ProductProbabilities

Calculates the product of item response probabilities for dichotomous ...

SignedArea

Calculates Raju's Signed Area Measure index for an item with given ite...

UnsignedArea

Calculates Raju's Unsigned Area Measure index for an item with given i...

A set of functions to perform Raju, van der Linden and Fleer's (1995, <doi:10.1177/014662169501900405>) Differential Functioning of Items and Tests (DFIT) analyses. It includes functions to use the Monte Carlo Item Parameter Replication approach (Oshima, Raju, & Nanda, 2006, <doi:10.1111/j.1745-3984.2006.00001.x>) for obtaining the associated statistical significance tests cut-off points. They may also be used for a priori and post-hoc power calculations (Cervantes, 2017, <doi:10.18637/jss.v076.i05>).

  • Maintainer: Victor H. Cervantes
  • License: GPL (>= 2)
  • Last published: 2021-08-17