is.Qid: Check whether a Q-matrix is identifiable

In cdmTools: Useful Tools for Cognitive Diagnosis Modeling

Check whether a Q-matrix is identifiable

Description

Checks whether a Q-matrix fulfills the conditions for strict and generic identifiability according to Gu & Xu (2021).

Usage

is.Qid(Q, model)

Arguments

Q	A J items x K attributes Q-matrix (matrix or data.frame).
model	CDM to be considered. It includes "DINA", "DINO", or "others" (for other CDMs; e.g., G-DINA, A-CDM).

Value

is.Qid returns an object of class is.Qid.

strict

Is the Q-matrix strictly identifiable? (logical).

generic

Is the Q-matrix generically identifiable? (logical).

conditions

Identifiability criteria and whether they are fulfilled or not (vector).

specifications

Function call specifications (list).

Author(s)

Pablo Nájera, Universidad Pontificia Comillas
Miguel A. Sorrel, Universidad Autónoma de Madrid

References

Gu, Y., & Xu, G. (2021). Sufficient and necessary conditions for the identifiability of the Q-matrix. Statistica Sinica, 31, 449-472. https://www.jstor.org/stable/26969691

Examples

Kj <- c(15, 10, 0, 5)
Q <- genQ(J = 30, K = 4, Kj = Kj, Qid = "others", seed = 123)$gen.Q
idQ <- is.Qid(Q, model = "DINA")

cdmTools documentation built on June 8, 2025, 12:34 p.m.