model.TIRT: Compute TIRT Pairwise Comparison Probabilities

In ForceChoice: Forced-Choice Modeling Based on Item Response Theory and Cognitive Diagnostic Models

Compute TIRT Pairwise Comparison Probabilities

Description

Compute TIRT Pairwise Comparison Probabilities

Usage

model.TIRT(theta, lambda, psi2, gamma.matrix, Q.matrix, pairs.matrix)

Arguments

theta	Latent trait matrix.
lambda	Factor loading magnitudes per statement. If signed values are supplied from a fitted object, the function uses abs(lambda) and the sign in Q.matrix carries the direction.
psi2	Uniqueness variances per statement.
gamma.matrix	Pairwise intercept matrix.
Q.matrix	Design Q-matrix.
pairs.matrix	Matrix of statement-index pairs.

Value

Matrix of pairwise choice probabilities: \Phi\{[-\gamma_{ik} + (|\lambda_i|q_i - |\lambda_k|q_k)'\theta_j] / \sqrt{\psi_i^2+\psi_k^2}\}.

ForceChoice documentation built on Sept. 13, 2026, 1:06 a.m.