Panel-generating function for visualizing the absolute item threshold parameters from the nodes in rasch, rating scale and partial credit tree models.
node_regionplot(mobobj, names = FALSE, abbreviate = TRUE,
type = c("mode", "median", "mean"), ref = NULL, ylim = NULL,
off = 0.1, col_fun = gray.colors, bg = "white", uo_show = TRUE, uo_col = "red",
uo_lty = 2, uo_lwd = 1.25, ylines = 2)
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
.
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.
logical. Should item names be abbreviated? If numeric this controls the length of the abbreviation.
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).
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.
y axis limits
numeric, the distance (in scale units) between two item rectangles.
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.
color for background filling.
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"
).
character, color of indication lines (if uo_show
).
numeric. Line typ of indication lines (if uo_show
).
numeric. Line width of indication lines (if uo_show
).
numeric. Number of lines used for y-axis labels.
A panel function which can be supplied to the plot
method
for "mob"
objects.
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
.