perturbDelta: perturbDelta

In conquestr: An R Package to Extend 'ACER ConQuest'

perturbDelta

Description

When probabilities are perturbed, the item difficulties may need to be updated to be location where p = 0.5

Usage

perturbDelta(myAbilities, myItems, myProbs)

Arguments

myAbilities	A matrix of perspon abilities.
myItems	A vector of item deltas.
myProbs	A matrix of response probabilities from n persons * i items.

Value

A matrix.

Examples

myAbilities <- rnorm(1000, 0, 1)
myItems <- runif (10, -2, 3)
myExProbs <- matrix(rnorm(100, 0, 1), 10, 10)
myExPerturb <- list(data.frame(item = 1, type = "flat", pivot = 0.5, factor = 25))
myProbs <- perturbProbs(myProbs = myExProbs, perturbP = myExPerturb)
myPerturbDelta <- perturbDelta(myAbilities = myAbilities, myItems = myItems, myProbs = myProbs)

conquestr documentation built on March 31, 2023, 6:02 p.m.