CDM (version 4.8-0)

IRT.itemfit: S3 Methods for Computing Item Fit

Description

This S3 method computes some selected item fit statistic.

Usage

IRT.itemfit(object, ...)

## S3 method for class 'din':
IRT.itemfit(object, method="RMSEA", \dots)

## S3 method for class 'gdina':
IRT.itemfit(object, method="RMSEA", \dots)

## S3 method for class 'gdm':
IRT.itemfit(object, method="RMSEA", \dots)

## S3 method for class 'slca':
IRT.itemfit(object, method="RMSEA", \dots)

Arguments

object

Object of classes din, gdina, gdm or slca.

method

Method for computing item fit statistic. Until now, only method="RMSEA" (see itemfit.rmsea) can be used.

...

More arguments to be passed.

Value

• Vector or data frame with item fit statistics.

See Also

For extracting the individual likelihood or posterior see IRT.likelihood or IRT.posterior.

Examples

#############################################################################
# EXAMPLE 1: DINA model item fit
#############################################################################

data(sim.dina)
data(sim.qmatrix)

# estimate model
mod1 <- din(sim.dina, sim.qmatrix)
# compute item fit
IRT.itemfit( mod1 )