create_prob_array {cat.dt}R Documentation

Multidimensional array of response probabilities

Description

For every item (dim 1) in an item bank and every evaluated ability level (dim 2), computes the probability of picking every possible response (dim 3) given the ability level

Usage

create_prob_array(model, bank, nres)

Arguments

model

polytomous IRT model. Options: "GRM" for Graded Response Model and "NRM" for Nominal Response Model

bank

matrix of the item bank. Rows represent items, and columns represent parameters. If the model is "GRM", the first column represents the alpha parameters and the next columns represent the beta parameters. If the model is "NRM", odd columns represent the alpha parameters and even columns represent beta parameters

nres

vector of number of possible responses for every item

Value

A 3-dimensional array of probability responses

Author(s)

Javier Rodríguez-Cuadrado


[Package cat.dt version 0.3.1 Index]