ItemParameterCompare: Plot comparing item parameters for common items

In CambridgeAssessmentResearch/unimirt: Applications of Unidimensional IRT using the R Package 'mirt'

Plot comparing item parameters for common items

Description

Common items are identified automatically on the basis of shared variable names.

Usage

ItemParameterCompare(mirtobj1, mirtobj2, compare = "Difficulties")

Arguments

mirtobj1	An estimated IRT model (of class SingleGroupClass) estimated either using the function "unimirt" or by applying the function "mirt" directly.
mirtobj2	An estimated IRT model (of class SingleGroupClass) estimated either using the function "unimirt" or by applying the function "mirt" directly.
compare	Character string equal to "Difficulties" (the default) or "Slopes" defining which item parameters should be compared.

Examples

## Not run: 
mirt1=unimirt(mathsdata[1:250,1:10])
mirt2=unimirt(mathsdata[251:500,6:15])

ItemParameterCompare(mirt1,mirt2, compare = "Difficulties")
ItemParameterCompare(mirt1,mirt2, compare = "Slopes")

## End(Not run)

CambridgeAssessmentResearch/unimirt documentation built on June 10, 2025, 6:03 a.m.