autoRasch (version 0.2.2)

plot_PImap: Plot The Person-Item Map

Description

This function maps the distribution of the persons' abilities and the items difficulties along the latent continuum.

Usage

plot_PImap(
  obj,
  main = NULL,
  xlab = NULL,
  cex = NULL,
  cex.lab = NULL,
  cex.axis = NULL,
  cex.main = NULL,
  lwd = NULL,
  v = NULL,
  th_dif = 1e-05
)

Value

There are no values to return. Instead, it shows a graphical map of the estimated ability and the estimated difficulty on the same scale.

Arguments

obj

The object of class 'pcm'.

main

main title of the plot; see plot.default().

xlab

Label for the x-axis; see plot.default().

cex

A numerical value giving the amount by which plotting text and symbols should be magnified relative to the default; see par().

cex.lab

The magnification to be used for x and y labels relative to the current setting of cex; see par().

cex.axis

The magnification to be used for axis annotation relative to the current setting of cex; see par().

cex.main

The magnification to be used for main titles relative to the current setting of cex; see par().

lwd

The line width, a positive number, defaulting to 1; see par().

v

Variable names used

th_dif

The threshold at which a DIF effect is still considered a DIF.

Examples

if (FALSE) {
groupsMap <- matrix(c(rep(1,50),rep(0,50)),ncol = 1, dimnames = list(c(1:100),c("V1")))
pcmdif_res <- pcm_dif(shortDIF, groups_map = groupsMap)
plot_PImap(pcmdif_res)
}