This function computes the ideal response pattern which is the latent item response \(\eta_{lj}=\prod_{k=1}^K \alpha_{lk}\) for a person with skill profile \(l\) at item \(j\).

ideal.response.pattern(q.matrix, skillspace=NULL, rule="DINA")

Arguments

q.matrix

The Q-matrix

skillspace

An optional skill space matrix. If it is not provided, then all skill classes are used for creating an ideal response pattern.

rule

Chosen condensation rule for the CDM. Can be "DINA" or "DINO".

Value

A list with following entries

idealresp

A matrix with ideal response patterns

skillspace

Used skill space

Examples

#############################################################################
# EXAMPLE 1: Ideal response pattern sim.qmatrix
#############################################################################

data(sim.qmatrix, package="CDM")
q.matrix <- sim.qmatrix

#- ideal response pattern for DINA model
CDM::ideal.response.pattern(q.matrix)

#- ideal response pattern for DINO model
CDM::ideal.response.pattern( q.matrix, rule="DINO" )

# compute ideal responses for a reduced skill space
skillspace <- matrix( c( 0,1,0,
                         1,1,0 ), 2,3, byrow=TRUE )
CDM::ideal.response.pattern( q.matrix, skillspace=skillspace)