CDM (version 8.2-6)

IRT.factor.scores: S3 Methods for Extracting Factor Scores (Person Classifications)

Description

This S3 method extracts factor scores or skill classifications.

Usage

IRT.factor.scores(object, ...)
# S3 method for din
IRT.factor.scores(object, type="MLE", ...)
# S3 method for gdina
IRT.factor.scores(object, type="MLE", ...)
# S3 method for mcdina
IRT.factor.scores(object, type="MLE", ...)
# S3 method for gdm
IRT.factor.scores(object, type="EAP", ...)
# S3 method for slca
IRT.factor.scores(object, type="MLE", ...)

Value

A matrix or a vector with classified scores.

Arguments

object

Object of classes din, gdina, mcdina, gdm or slca.

type

Type of estimated factor score. This can be "MLE", "MAP" or "EAP". The type EAP cannot be used for objects of class slca.

...

More arguments to be passed.

See Also

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

Examples

#############################################################################
# EXAMPLE 1: Extracting factor scores in the DINA model
#############################################################################

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

# estimate DINA model
mod1 <- CDM::din( sim.dina, q.matrix=sim.qmatrix)
summary(mod1)
# MLE
fsc1a <- CDM::IRT.factor.scores(mod1)
# MAP
fsc1b <- CDM::IRT.factor.scores(mod1, type="MAP")
# EAP
fsc1c <- CDM::IRT.factor.scores(mod1, type="EAP")
# compare classification for skill 1
stats::xtabs( ~ fsc1a[,1] + fsc1b[,1] )
graphics::boxplot( fsc1c[,1] ~ fsc1a[,1] )