CSEMfromMirt: Function to calculate conditional standard error of...

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

Function to calculate conditional standard error of measurement at each true score

Description

Calculates the conditional standard error of measurement at each unit true score on the test (totalled across a given selection of items). This is defined as the standard deviation of observed scores given the true score.

Usage

CSEMfromMirt(mirtobj, which.items = NULL)

Arguments

mirtobj	An estimated IRT model (of class SingleGroupClass) estimated either using mirt or unimirt. Must be fitted using the (default) "EM" method. Must be unidimensional.
which.items	A vector of denoting which items should be included in calculating the score.

Value

The function returns a data.frame with columns: true.score (a vector of possible integer true scores) , and csem (the standard deviation of obsereved scores for candidates with the given true score).

Examples

## Not run: 
mirt1=unimirt(mathsdata,"2")
CSEMfromMirt(mirt1)

## End(Not run)

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