waldtest.psy: Fischer and Scheiblechner's "wald-like" S-statistic for...

In exhaustiveRasch: Item Selection and Exhaustive Search for Rasch Models

Fischer and Scheiblechner's "wald-like" S-statistic for psychotools

Description

Fischer and Scheiblechner's "wald-like" S-statistic for psychotools

Usage

waldtest.psy(
  model,
  modelType,
  splitcr = "median",
  splitseed = NULL,
  icat = FALSE
)

Arguments

model	an object of 'psychotools' class 'raschmodel', 'pcmodel' or 'rsmodel' (a model previously fit using the 'psychotools' package) matching the value of modelType.
modelType	a character value defining the type of Rasch model. Possible values: "RM", "PCM", "RSM"
splitcr	split criterion for subject raw score splitting. "median" uses the median as split criterion, "mean" performs a mean-split, "random" performs a random split (in this case, the seed can be set with the "splitseed" argument. Optionally splitcr can also be a dichotomous vector which assigns each person to a certain subgroup (typically an external criterion). This vector can be numeric, character or a factor.
splitseed	seed for random split
icat	a boolean value defining wether to use item parameters ('psychotools' function 'itempar', if TRUE) or item category parameters ('psychotools' function 'threshpar')

Value

a vector containing the p-values of the Scheiblechner's "wald-like" S-statistic for the items (if icat=FALSE) or for the item categories (if icat=TRUE).

Examples

 model <- psychotools::raschmodel(ADL[c(6,7,12,14,15)])
   waldtest.psy(model=model, modelType="RM", splitcr="random", splitseed=332,
   icat=FALSE)

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