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| Ase1pl | Calculates the asymptotic variance for difficulty parameter estimates under the 1pl model |
| Ase2pl | Calculates the asymptotic covariance matrix of item parameter estimates under the 2pl model |
| Ase3pl | Calculates the asymptotic covariance matrix of item parameter estimates under the 3pl model |
| AseIrt | Calculates the asymptotic covariance matrices for item parameters according with the IRT model. |
| Bound3PlIpr | Takes item parameters from Ipr and forces guessing to lie between 0 and 1 |
| Bound4PlIpr | Takes item parameters from Ipr and forces guessing to lie between 0 and 1 |
| 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 curves for all options (minus one). |
| CalculatePcmExp | Calculates the expected item score under the (G)PCM model. |
| Cdif | Calculates CDIF index for an item with given item parameters of focal and reference groups. |
| 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 denominator of the odds-ratio under dichotomous IRT models |
| CutoffIpr | Cut-off points for Ipr generated estimates |
| DeltaMhIrt | Obtains the ETS Delta measure for Mantel-Haneszel DIF statistic effect size. |
| DFIT | Differential Functioning of Items and Tests framework |
| dichotomousItemParameters | Sets of focal and reference item parameters from Wright (2011). |
| Dtf | Calculates DTF index for a set of items with given item parameters of focal and reference groups. |
| Extract2PLMirt | Extract item discrimination and difficulties and estimate covariance estimates for 2PL items from a fitted mirt object for one or two groups |
| Extract3PLMirt | Extract item discrimination, difficulties, and guessing parameters and estimate covariance estimates for 3PL items from a fitted mirt object for one or two groups |
| Extract4PLMirt | 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 |
| ExtractGPCMMirt | Extract item discrimination and difficulties and estimate covariance estimates for GPCM items from a fitted mirt object for one or two groups |
| ExtractGRMMirt | Extract item discrimination and difficulties and estimate covariance estimates for GRM items from a fitted mirt object for one or two groups |
| ExtractMirtPars | Extracts the item parameters from a unidimensional mirt model |
| ExtractRaschMirt | Extract item difficulties and item difficulty variance estimates for Rasch items from a fitted mirt object for one or two groups |
| Ipr | Item parameter replication |
| IprMh | Mantel Haenszel for Item parameter replication |
| 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 dichotomous IRT model holds |
| Ncdif | Calculates NCDIF index for an item with given item parameters of focal and reference groups. |
| PlotNcdif | Plot the item characteristic (expected score) curve for focal and reference groups for the iiItem along with a representation of the focal group density. |
| polytomousItemParameters | Sets of focal and reference item parameters from Raju et al. (2009) |
| ProductProbabilities | Calculates the product of item response probabilities for dichotomous IRT models |
| SignedArea | Calculates Raju's Signed Area Measure index for an item with given item parameters of focal and reference groups. |
| UnsignedArea | Calculates Raju's Unsigned Area Measure index for an item with given item parameters of focal and reference groups. |