scoreProbability.theta.3pl: Calculate the probability of each possible score for the...

In yuehmeir2/CATSimulator: Library for Simulation of Adaptive Item Selection

Description

Calculate the probability of each possible score for the given 3PL items and a specific theta

Usage

scoreProbability.theta.3pl(item_pars, theta)

Arguments

item_pars	a matrix of doubles, items by params. Must have columns for $PAR_* matching the $MODEL
theta	a double. An ability level

Value

a matrix of doubles, items by scores, containing the probability of each possible score for the given items and a specific theta

Examples

  simulation = readRDS(system.file("example/passage-optimal.rds", package = "CATSimulator"))
  item_pars = as.matrix(simulation$itempool[,startsWith(colnames(simulation$itempool), "PAR_")])
  dimnames(item_pars) = list(simulation$itempool$ITEM_ID, colnames(simulation$itempool)[startsWith(colnames(simulation$itempool), "PAR_")])
  theta = 2.0
  scoreProb = scoreProbability.theta.3pl(item_pars, theta)
  options(digits=8, scipen=8)
  > scoreProb       0          1
  item042 0.649862455 0.35013754
  item043 0.688542983 0.31145702
  item044 0.290662804 0.70933720
  item045 0.234881989 0.76511801
  item048 0.576947540 0.42305246
  item049 ...277 total items/rows

yuehmeir2/CATSimulator documentation built on June 13, 2021, 7:02 p.m.