Plot the item map (location against fit residual)

Items plotted by location and fit residual, with the conventional acceptance band at +/- 2.5 and misfitting items labelled.

Usage

plot_item_map(fit, band = 2.5)

Arguments

fit

A fitted object from rasch.

band

Fit residual acceptance band.

Value

Called for its plotting side effect; invisibly NULL.

Examples

set.seed(1)
d <- seq(-2, 2, length.out = 6)
X <- matrix(rbinom(400 * 6, 1, plogis(outer(rnorm(400), d, "-"))), 400, 6)
colnames(X) <- paste0("I", 1:6)
plot_item_map(rasch(X))