if (FALSE) {
#############################################################################
# EXAMPLE 1: Transformation PCM for data.mg
#############################################################################
library(CDM)
data(data.mg,package="CDM")
dat <- data.mg[ 1:1000, paste0("I",1:11) ]
#*** Model 1: estimate partial credit model in parameterization "PCM"
mod1a <- TAM::tam.mml( dat, irtmodel="PCM")
# use parameterization "PCM2"
mod1b <- TAM::tam.mml( dat, irtmodel="PCM2")
summary(mod1a)
summary(mod1b)
# convert parameterization of Model 1a into parameterization of Model 1b
b <- mod1a$item[, c("AXsi_.Cat1","AXsi_.Cat2","AXsi_.Cat3") ]
# compare results
pcm.conversion(b)
mod1b$xsi
}
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