personfitPlot: Plotting personfit estimates

In masurp/ggmirt: Plotting functions to extend "mirt" for IRT analyses

Plotting personfit estimates

Description

This function takes a fitted mirt-model and visualizes person infit and outfit estimates. The function builds on mirt::itemfit(). The basic idea is to visualize how many individuals in the sample do not show a response pattern that aligns with the suggested model. At best, the number of non-fitting response patterns is low (e.g., < 5%).

Usage

personfitPlot(model, std = TRUE, title = "Person Infit and Outfit Statistics")

Arguments

model	an object of class SingleGroupClass returned by the function mirt().
std	logical value indicating whether standardized or non-standardized infit or outfit estimates should be used (leads to different cut-off values).
title	title for the plot (defaults to "Person Infit and Outfit Statistics")

Value

a ggplot

References

• Linacre JM. (2002). What do Infit and Outfit, Mean-square and Standardized mean? Rasch Measurement Transactions, 16(2), p.878. https://www.rasch.org/rmt/rmt162f.htm

Examples

library(mirt)
library(ggmirt)
data <- expand.table(LSAT7)
(mod <- mirt(data, 1))

personfitPlot(mod, std = F)

masurp/ggmirt documentation built on Oct. 14, 2023, 1:16 p.m.