plot.imp: A plot method for the interaction model

In irtoys: A Collection of Functions Related to Item Response Theory (IRT)

A plot method for the interaction model

Description

Plot the item-total regressions fit by the interaction (or Rasch) model

Usage

## S3 method for class 'imp'
plot(
  x,
  items = NULL,
  shade = 10,
  highlight = -Inf,
  add = FALSE,
  main = "Item-total regression",
  label = FALSE,
  ...
)

Arguments

x	An object produced by function interactionModel
items	The items to plot (column numbers). If NULL, all items will be plotted
shade	The part of the probability mass for the sum scores to shade out, shown as percentage. Default is 10: shade the most extreme 10 Ignored when add=TRUE.
highlight	Cutpoint for the interaction parameter below which a regression line will be highlighted in red. Default is -Inf (do not highlight).
add	When add=TRUE, the graph is added to a plot, otherwise a new plot is started. Default is FALSE.
main	The main title of the plot, given that add=FALSE.
label	When label=TRUE, individual curves will be labeled with the item number.
...	Any additional plotting parameters

Author(s)

Ivailo Partchev, using theory and C code by Gunter Maris

See Also

interactionModel

Examples

plot(interactionModel(Scored), highlight=-.3)

irtoys documentation built on May 12, 2022, 5:06 p.m.