mscatdif: Multistage CAT DIF Function

In faffr/mscatdif: Multi-Stage Computer Adaptive Test Differential Item Functioning

Description

This function performs DIF analysis on items from a multi-stage CAT

Usage

mscatdif(scored.resp, person.ability, item.difficulty, group.info,
  which.focal = NULL, which.ref = NULL, item.fit = NULL,
  item.names = NULL, outfilename = NULL, purification = FALSE,
  field.test = FALSE, FTnSize = NULL)

Arguments

scored.resp	is a matrix of scored responses.
person.ability	is a vector of person ability estimates.
item.difficulty	is a vector of item difficulty measures.
group.info	is a vector of person demographic variable.
which.focal	is the desired focal group. Random group chosen if NULL.
which.ref	is the desired reference group. Random group chosen if NULL.
item.fit	is a vector of item fit information. Default = NULL.
item.names	is a vector of item names. Default = NULL.
outfilename	is the name of the desired .csv output file. Default = NULL.
purification	run purification? Default = FALSE.
field.test	is it a field test? Default = FALSE.
FTnSize	if !is.null(field.test) then FTnSize integer scalar must be specified.

Examples

set.seed(1010)
ItemData = matrix(sample(rep(0:1, each = 1000),1000),100,10)
PersMeas = rnorm(100, 0, 1)
DemogGroup = sample(rep(c("O","H"), each = 100), 100)
ItemMeas = rnorm(10, 0, 1)
mscatdif(ItemData, PersMeas, ItemMeas, DemogGroup)

faffr/mscatdif documentation built on May 19, 2019, 4:05 p.m.