IRT.itemfit function

S3 Methods for Computing Item Fit

This S3 method computes some selected item fit statistic.

IRT.itemfit(object, ...)

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

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

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

## S3 method for class 'reglca'
IRT.itemfit(object, method="RMSEA", ...)

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

Arguments

• object: Object of classes din, gdina, gdm, slca, reglca.
• method: Method for computing item fit statistic. Until now, only method="RMSEA" (see itemfit.rmsea) can be used.
• ...: More arguments to be passed.

Returns

Vector or data frame with item fit statistics.

See Also

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

Examples

## Not run:

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

data(sim.dina, package="CDM")
data(sim.qmatrix, package="CDM")

# estimate model
mod1 <- CDM::din( sim.dina, q.matrix=sim.qmatrix)
# compute item fit
IRT.itemfit( mod1 )
## End(Not run)