plot.DIFtree {DIFtree} | R Documentation |
Plotting of Item focussed Trees
Description
Visualization of trees for items with DIF identified by item focussed recursive partitioning in dichotomous or polytomous items.
Usage
## S3 method for class 'DIFtree'
plot(x, item, component = "intercept", cex.lines = 2,
cex.branches = 1, cex.coefs = 1, cex.main = 1, title = NULL, ...)
Arguments
x |
Object of class |
item |
Number of the item, for which the tree shall be plotted |
component |
Component of the model for which the tree shall be plotted;
can be |
cex.lines |
Width of branches of the tree |
cex.branches |
Size of the labels of branches of the tree |
cex.coefs |
Size of coefficients in the terminal nodes of the tree |
cex.main |
Size of the title of the tree |
title |
Optional title, which is added to the tree;
if |
... |
Further arguments passed to or from other methods |
Author(s)
Moritz Berger <moritz.berger@imbie.uni-bonn.de>
http://www.imbie.uni-bonn.de/personen/dr-moritz-berger/
References
Berger, Moritz and Tutz, Gerhard (2016): Detection of Uniform and Non-Uniform Differential Item Functioning by Item Focussed Trees, Journal of Educational and Behavioral Statistics 41(6), 559-592.
Bollmann, Stella, Berger, Moritz & Tutz, Gerhard (2018): Item-Focussed Trees for the Detection of Differential Item Functioning in Partial Credit Models, Educational and Psychological Measurement 78(5), 781-804.
Tutz, Gerhard and Berger, Moritz (2016): Item focussed Trees for the Identification of Items in Differential Item Functioning, Psychometrika 81(3), 727-750.
See Also
DIFtree
, predict.DIFtree
, summary.DIFtree
Examples
data(data_sim_Rasch)
Y <- data_sim_Rasch[,1]
X <- data_sim_Rasch[,-1]
## Not run:
mod <- DIFtree(Y=Y,X=X,model="Logistic",type="udif",alpha=0.05,nperm=1000,trace=TRUE)
plot(mod,item=1)
## End(Not run)