# NOT RUN {
# Loading of the verbal data
data(verbal)
attach(verbal)
# Splitting the data into reference and focal groups
nF <- sum(Gender)
nR <- nrow(verbal)-nF
data.ref <- verbal[,1:24][order(Gender),][1:nR,]
data.focal <- verbal[,1:24][order(Gender),][(nR+1):(nR+nF),]
# Pre-estimation of the item parameters (1PL model)
mR <- itemParEst(data.ref,model = "1PL")
mF <- itemParEst(data.focal,model = "1PL")
mF <- itemRescale(mR, mF)
# Signed and unsigned Raju statistics
RajuZ(mR, mF)
RajuZ(mR, mF, signed = TRUE)
# Pre-estimation of the item parameters (2PL model)
mR <- itemParEst(data.ref, model = "2PL")
mF <- itemParEst(data.focal, model = "2PL")
mF <- itemRescale(mR, mF)
# Signed and unsigned Raju statistics
RajuZ(mR, mF)
RajuZ(mR, mF, signed = TRUE)
# Pre-estimation of the item parameters (constrained 3PL model)
mR <- itemParEst(data.ref, model = "3PL", c = 0.05)
mF <- itemParEst(data.focal, model = "3PL", c =0 .05)
mF <- itemRescale(mR, mF)
# Signed and unsigned Raju statistics
RajuZ(mR, mF)
RajuZ(mR, mF, signed = TRUE)
# }
# NOT RUN {
# }
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