dendrify2: Expandsion of item responses based on an item resonse tree
In seonghobae/flirt.x32: Flexible Item Response Theory Modeling

Description Usage Arguments Author(s) References See Also Examples

Expands a wide-form matrix of item responses based on an item response tree structure

1 2	## S3 method for class 'flirt' dendrify2(mat, cmx, missing.omit=FALSE, wide=FALSE)

`mat`	an integer matrix of IRT responses (columns represent items, rows represent respondents)
`cmx`	a mapping matrix with as many rows as there are response options for the items
`missing`	for a long-form data, the data lines with a missing item response are removed
`wide`	If `TRUE`, expanded data are provided in a wide form

Minjeong Jeon <jeon.117@osu.edu>

De Boeck, P. and Partchev, I. (2012). IRTrees: Tree-Based Item Response Models of the GLMM Family, Journal of Statistical Software 48, 1-8.

Jeon, M. and De Boeck, P. (2015). A generalized item response tree model for psychological assessments. Under revision.

flirt

library(flirt)

## verbal aggression data

data(verb2)

# expand the data based on a tree structure (mapping matrix)
mapping <- cbind(c(0, 1, 1), c(NA, 0, 1))
wide <- dendrify2(verb2, mapping, wide=TRUE)