Open Access. Powered by Scholars. Published by Universities.®

Education Commons

Open Access. Powered by Scholars. Published by Universities.®

Educational Assessment, Evaluation, and Research

USF Tampa Graduate Theses and Dissertations

2013

Misspecification of the Q-matrix

Articles 1 - 1 of 1

Full-Text Articles in Education

The Performance Of The Linear Logistic Test Model When The Q-Matrix Is Misspecified: A Simulation Study, George T. Macdonald Nov 2013

The Performance Of The Linear Logistic Test Model When The Q-Matrix Is Misspecified: A Simulation Study, George T. Macdonald

USF Tampa Graduate Theses and Dissertations

A simulation study was conducted to explore the performance of the linear logistic test model (LLTM) when the relationships between items and cognitive components were misspecified. Factors manipulated included percent of misspecification (0%, 1%, 5%, 10%, and 15%), form of misspecification (under-specification, balanced misspecification, and over-specification), sample size (20, 40, 80, 160, 320, 640, and 1280), Q-matrix density (60% and 46%), number of items (20, 40, and 60 items), and skewness of person ability distribution (-0.5, 0, and 0.5). Statistical bias, root mean squared error, confidence interval coverage, confidence interval width, and pairwise cognitive components correlations were computed. The impact …