model.transform: Model transformations

In IRTpp: Estimating IRT Parameters using the IRT Methodology

Description

Implements parameter transforms from one parameter to others dependent on the model Currently only 3PL, supported with passings between b <-> d and c <-> cp'

Usage

model.transform(z, model, src, target, byrow = F)

Arguments

z	The parameter matrix or named list.
model	The model to transform.
src	The original parameter to transform.
target	The target parameter of the transform.
byrow	Read matrix by row.

Value

z The parameters with the transform.

Examples

## create the dataset
# data <- simulateTest(model = "3PL", items = 20, individuals = 200)
## extract the parameters and transform them from one list to matrix.
# zita <-data$itempars
# zita <- list(zita$a, zita$b, zita$c)
# zita <- parameter.matrix(zita)
## transform the model parameters
# model.transform(zita, model = "3PL", src = "b", target = "d")
# model.transform(zita, model = "3PL", src = "c", target = "cp")

IRTpp documentation built on May 29, 2017, 9:58 a.m.