item_obsexp: Observed and expected item mean scores

Description Usage Arguments Value Author(s) Examples

View source: R/Item-Fit.R

Description

Homogeneity of item responses in the low and high score groups is analyzed by looking at observed and expected item mean scores together with standardized residuals. If the Andersen's CLR test has shown some evidence against homogeneity, this comparison can indicate which items might be responsable.

Usage

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item_obsexp(object)

Arguments

object

object of class "Rm", a fitted Rasch model oder partial credit model using the functions RM or PCM in package eRm.

Value

list with observed and expected mean scores together with standardized residuals for the two score groups.

Author(s)

Marianne Mueller

Examples

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rm.mod <- RM(amts[,4:13])
item_obsexp(rm.mod)

pc.mod <- PCM(desc2[,5:14])
item_obsexp(pc.mod)

muellermarianne/iarm documentation built on June 7, 2018, 1:13 p.m.