Plot the test information function

Test information across the logit scale with the standard error of measurement overlaid on a second axis.

Usage

plot_tif(fit, grid = NULL)

Arguments

fit

A fitted object from rasch.

grid

Logit grid.

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_tif(rasch(X))