# eta: Ideal Response Patterns for all possible attribute profiles In ACTCD: Asymptotic Classification Theory for Cognitive Diagnosis

## Description

This function is used to calculate ideal response patterns for all possible attribute profiles based on the DINA model (Junker & Sijtsma, 2001) or conjunctive-type cognitive diagnostic models.

## Usage

 1 eta(K, J, Q)

## Arguments

 K The number of attributes. J The number of items. Q A required J \times K binary item-by-attribute association matrix (Q-matrix), where K is the number of attributes. The j^{th} row of the matrix is an indicator vector, 1 indicating attributes are required and 0 indicating attributes are not required to master item j.

## Value

A 2^K \times J binary matrix will be returned. Each row of ideal response patterns is corresponding to each of the 2^K possible attribute patterns, which can be obtained from alpha.

## References

Junker, B., & Sijtsma, K. (2001). Cognitive Assessment Models with Few Assumptions, and Connections with Nonparametric Item Response Theory. Applied Psychological Measurement, 25(3), 258-272.