immer_unique_patterns: Extracts Unique Item Response Patterns

In immer: Item Response Models for Multiple Ratings

Extracts Unique Item Response Patterns

Description

Extracts unique item response patterns.

Usage

immer_unique_patterns(dat, w=rep(1, nrow(dat)))

Arguments

dat	Data frame containing integer item responses
w	Optional vector of weights

Value

A list with entries

y	Data frame with unique item response patterns
w	Vector of frequency weights
y_string	Item response pattern coded as a string

See Also

See mirt::expand.table for back-converting unique item response patterns into a data frame with item responses.

Examples

#############################################################################
# EXAMPLE 1: Unique item response patterns data.read
#############################################################################

data( data.read, package="sirt")
dat <- data.read

# extract item response patterns
res <- immer::immer_unique_patterns(dat)

## Not run: 
# back-conversion with expand.table
dat2 <- mirt::expand.table( cbind( res$y, res$w ) )
# check correctness
colMeans(dat)
colMeans(dat2)

## End(Not run)

immer documentation built on May 29, 2024, 11:52 a.m.