Calculates the asymptotic variance for difficulty parameter estimates under the 1pl model
Calculates the item success probability under the 1PL model.
Calculates the item success probability under the 2PL model.
Identifies items with upper asymptote outside [0, 1]
Calculates the crossed probabilities associated with the numerator and denominator of the odds-ratio under dichotomous IRT models
Differential Functioning of Items and Tests framework
Cut-off points for Ipr generated estimates
Extract item difficulties and item difficulty variance estimates for Rasch items from a fitted mirt object
for one or two groups
Item parameter replication
Mantel Haenszel for Item parameter replication
Calculates the expected item score under the GRM model.
Calculates the asymptotic covariance matrix of item parameter estimates under the 3pl model
Extract item discrimination and difficulties and estimate covariance estimates for GPCM items from a fitted mirt object
for one or two groups
Unsigned Area Measure for Item parameter replication
Signed Area Measure for Item parameter replication
Extract item discrimination, difficulties, guessing, and upper asymptote parameters and estimate covariance estimates for 4PL items from a fitted mirt object
for one or two groups
NCDIF for Item parameter replication
Calculates the item success probability under the 3PL model.
Extract item discrimination and difficulties and estimate covariance estimates for GRM items from a fitted mirt object
for one or two groups
Calculates the expected item score under the (G)PCM model.
Calculates the item success probability under the 4PL model.
Calculates CDIF index for an item with given item parameters of focal and reference groups.
Calculates Raju's Signed Area Measure index for an item with given item parameters of focal and reference groups.
Plot the item characteristic (expected score) curve for focal and reference groups for the iiItem along with a
representation of the focal group density.
Extracts the item parameters from a unidimensional mirt model
Calculates Raju's Unsigned Area Measure index for an item with given item parameters of focal and reference groups.
Calculates the product of item response probabilities for dichotomous IRT models
Calculates the asymptotic covariance matrices for item parameters according with the IRT model.
Calculates DTF index for a set of items with given item parameters of focal and reference groups.
Identifies items with guessing outside [0, 1]
Identifies items with nonpositive discrimination
Obtains the ETS Delta measure for Mantel-Haneszel DIF statistic effect size.
Extract item discrimination, difficulties, and guessing parameters and estimate covariance estimates for 3PL items from a fitted mirt object
for one or two groups
Calculates the differences between two item option characteristic curves for all options (minus one).
Extract item discrimination and difficulties and estimate covariance estimates for 2PL items from a fitted mirt object
for one or two groups
Calculates the Mantel-Haenszel theoretical parameter when a dichotomous IRT model holds
dichotomousItemParameters
Sets of focal and reference item parameters from Wright (2011).
Sets of focal and reference item parameters from Raju et al. (2009)
Calculates NCDIF index for an item with given item parameters of focal and reference groups.
Calculates the asymptotic covariance matrix of item parameter estimates under the 2pl model
Takes item parameters from Ipr and forces guessing to lie between 0 and 1
Takes item parameters from Ipr and forces guessing to lie between 0 and 1