TY - JOUR
AU - Baghaei, Purya
AU - Hohensinn, Christine
PY - 2017
M3 - 10.3389/fpsyg.2017.00897
SP - 897
TI - A Method of Q-Matrix Validation for the Linear Logistic Test Model
JO - Frontiers in Psychology
UR - https://www.frontiersin.org/article/10.3389/fpsyg.2017.00897
VL - 8
SN - 1664-1078
N2 - The linear logistic test model (LLTM) is a well-recognized psychometric model for examining the components of difficulty in cognitive tests and validating construct theories. The plausibility of the construct model, summarized in a matrix of weights, known as the Q-matrix or weight matrix, is tested by (1) comparing the fit of LLTM with the fit of the Rasch model (RM) using the likelihood ratio (LR) test and (2) by examining the correlation between the Rasch model item parameters and LLTM reconstructed item parameters. The problem with the LR test is that it is almost always significant and, consequently, LLTM is rejected. The drawback of examining the correlation coefficient is that there is no cut-off value or lower bound for the magnitude of the correlation coefficient. In this article we suggest a simulation method to set a minimum benchmark for the correlation between item parameters from the Rasch model and those reconstructed by the LLTM. If the cognitive model is valid then the correlation coefficient between the RM-based item parameters and the LLTM-reconstructed item parameters derived from the theoretical weight matrix should be greater than those derived from the simulated matrices.
ER -