expected.rc: Expected scores under the PCM or the GPCM.

In classify: Classification Accuracy and Consistency under IRT models.

Description

Calculates expected scores under the PCM or the GPCM.

Usage

  expected.rc(beta=NULL,theta=NULL,cats=NULL,alpha=NULL)

Arguments

beta	Matrix of Beta parameters
theta	Vector of Theta parameters
cats	Vector Item category parameters
alpha	Vector of Alpha parameters (optional)

Details

The beta parameters are the intersection points of adjacent category information functions. There should be one less delta parameter than categories. Assumes that the location parameter is zero. If no alpha parameters are supplied it assumes the PCM.

Value

Vector of expected scores

Examples

#One item with three categories
beta <- matrix(c(0,-1.586,-3.798),nrow=1,ncol=3)
theta <- 0.674
cats <- 3
alpha <- 1
expected.rc(beta,theta,cats,alpha)

classify documentation built on May 29, 2017, 7:49 p.m.