findmodel: The model of each item in a mixed test

In PP: Person Parameter Estimation

The model of each item in a mixed test

Description

This function shows which model PPall() uses for each item: an item with one threshold is a 4PL item, an item with several thresholds a GPCM item.

Usage

findmodel(thres)

Arguments

thres

A numeric matrix which contains the threshold parameter for each item. NA is allowed - in fact expected!

Details

Up to version 0.6.4-1 its result was passed to PPall() as model2est. This is no longer needed: PPall() derives the model of each item from thres in the same way.

Value

A character vector with one entry per item (column of thres): "4PL" for items with one threshold, "GPCM" for items with more.

Author(s)

Manuel Reif

See Also

PPall

Examples

thres <- rbind(0, c(-1, 0.5, -0.2), c(NA, 1.2, 0.4))
findmodel(thres)

PP documentation built on Oct. 15, 2026, 1:06 a.m.