test_DIFtree: builds a raschtree using the raschtree or rstree function of...

In exhaustiveRasch: Item Selection and Exhaustive Search for Rasch Models

builds a raschtree using the raschtree or rstree function of the psychotree Package.

Description

builds a raschtree using the raschtree or rstree function of the psychotree Package.

Usage

test_DIFtree(
  items = NULL,
  DIFvars = NULL,
  dset = NULL,
  na.rm = TRUE,
  model = NULL,
  p.par = NULL,
  modelType = NULL,
  alpha = 0.1,
  estimation_param = NULL
)

Arguments

items	a numeric vector containing the index numbers of the items in dset that are used to fit the model
DIFvars	a vector or a data.frame containing the external variable(s) to test for differential item functioning
dset	a data.frame containing the data
na.rm	a boolean value. If TRUE, all cases with any NA are removed (na.omit). If FALSE, only cases with full NA responses are removed
model	on object of a fit Rasch model, estimated with the packages 'eRm' (classes 'RM', 'PCM' or 'RSM'), 'psychotools' (classes raschmodel, 'pcmodel' or 'rsmodel') or 'pairwise' (class 'pers'), matching the value of modelType. If 'model' is provided, this model is used. If NULL, a model is fit using 'dset' and 'items'.
p.par	a person parameter object matching the class of 'model'. If NULL, the person parameters will be estimated.
modelType	a character value defining the rasch model to fit. Possible values: "RM", "PCM", "RSM".
alpha	a numeric value for the alpha level. Will be ignored if use.pval is FALSE
estimation_param	options for parameter estimation using estimation_control

Value

if none of the p-values is significant, a list containing 3 elements is returned: the item combination that was tested, a list of the class the model was estimated with (depending on modelType and estimation_param$est) with the fit model and a list with a person parameter object (depending on estimation_param$est). If there is at least one item with a significant p-value, NULL is returned.

exhaustiveRasch documentation built on April 3, 2025, 6:18 p.m.