plot.DIF_stats: plot method for pairwise DIF statistics

In dexter: Data Management and Analysis of Tests

plot method for pairwise DIF statistics

Description

plot method for pairwise DIF statistics

Usage

## S3 method for class 'DIF_stats'
plot(
  x,
  items = NULL,
  itemsX = items,
  itemsY = items,
  cluster = FALSE,
  alpha = 0.05,
  ...
)

Arguments

x	object produced by DIF
items	character vector of item id's for a subset of the plot. Useful if you have many items. If NULL all items are plotted.
itemsX	character vector of item id's for the X axis
itemsY	character vector of item id's for the Y axis
cluster	arrange items by similarity.
alpha	significance level used to color the plot (two sided)
...	further arguments to plot

Details

Plotting produces an image of the matrix of pairwise DIF statistics. The statistics are standard normal deviates and colored to distinguish significant from non-significant values. If there is no DIF, a proportion alpha off the cells will be colored significant by chance alone.

dexter documentation built on April 11, 2025, 5:45 p.m.