node_regionplot: Panel-Generating Function for Visualizing Rasch, Rating Scale...

Description Usage Arguments Details Value See Also

View source: R/graphics.R

Description

Panel-generating function for visualizing the absolute item threshold parameters from the nodes in rasch, rating scale and partial credit tree models.

Usage

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node_regionplot(mobobj, names = FALSE, abbreviate = TRUE,
  type = c("mode", "median", "mean"), ref = NULL, ylim = NULL,
  off = 0.1, col_fun = gray.colors, uo_show = TRUE, uo_col = "red",
  uo_lty = 2, uo_lwd = 1.25, ylines = 2)

Arguments

mobobj

an object of class "mob" based on rasch models fitted by raschmodel, rating scale models fitted by rsmodel or partial credit models fitted by pcmodel.

names

logical or character. If TRUE, the names of the items are displayed on the x-axis. If FALSE, numbers of items are shown. Alternatively a character vector of the same length as the number of items can be supplied.

abbreviate

logical. Should item names be abbreviated? If numeric this controls the length of the abbreviation.

type

character, specifying which type of threshold parameters are to be used to mark the category regions per item in the plot (see regionplot for details).

ref

a vector of labels or position indices of item parameters which should be used as restriction/for normalization. If NULL (the default), all items are used (sum zero restriction). See threshpar for more details.

ylim

y axis limits

off

numeric, the distance (in scale units) between two item rectangles.

col_fun

function. Function to use for creating the color palettes for the rectangles. Per default gray.colors is used. Be aware that col_fun should accept as first argument an integer specifying the number of colors to create.

uo_show

logical. If set to TRUE (the default), disordered absolute item threshold parameters are indicated by a horizontal line (only if type is set to "mode").

uo_col

character, color of indication lines (if uo_show).

uo_lty

numeric. Line typ of indication lines (if uo_show).

uo_lwd

numeric. Line width of indication lines (if uo_show).

ylines

numeric. Number of lines used for y-axis labels.

Details

The panel-generating function node_regionplot is called by the plot method of "rstree" and "pctree" objects by default and does not have to be called by the user directly.

See regionplot for details and references of the drawn region plots and possible values and their meaning for the argument type (taken by node_regionplot).

Prior to version 0.13-1, node_regionplot was called node_effects.

Value

A panel function which can be supplied to the plot method for "mob" objects.

See Also

raschtree, rstree, pctree, regionplot


psychotree documentation built on May 29, 2017, 3:11 p.m.