ltm: mult.choice – R documentation

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Documentation

ltm

mult.choice

Multiple Choice Items to Binary Responses

Description

It converts multiple choice items to a matrix of binary responses.

Usage

mult.choice(data, correct)

Arguments

`data`	a `matrix` or a `data.frame` containing the manifest variables as columns.
`correct`	a vector of length `ncol(data)` with the correct responses.

Value

a matrix of 0/1 values indicating wrong/correct answers.

Author(s)

Dimitris Rizopoulos d.rizopoulos@erasmusmc.nl

Examples

dat <- data.frame(It1 = sample(4, 100, TRUE),
                  It2 = sample(4, 100, TRUE),
                  It3 = sample(5, 100, TRUE),
                  It4 = sample(5, 100, TRUE),
                  It5 = sample(4, 100, TRUE),
                  It6 = sample(5, 100, TRUE))
dat[] <- lapply(dat, function (x) { x[sample(100, 4)] <- NA; x })
crct <- c(3, 2, 5, 3, 4, 5)
####################
mult.choice(dat, crct)

ltm

Latent Trait Models under IRT

v1.1-1

GPL (>= 2)

Authors

Dimitris Rizopoulos <d.rizopoulos@erasmusmc.nl>

Initial release

2018-04-17