Related Experiment Video
Updated: Apr 27, 2026

A Psychophysics Paradigm for the Collection and Analysis of Similarity Judgments
Published on: March 1, 2022
Performance of the likelihood ratio difference (G2 Diff) test for detecting unidimensionality in applications of the
Leigh Harrell-Williams1, Edward W Wolfe
1Edward W. Wolfe, Pearson, 3974 Roberts Ridge, NE, Iowa City, IA 52240, USA, ed.wolfe@pearson.com.
Abstract:
Previous research has investigated the influence of sample size, model misspecification, test length, ability distribution offset, and generating model on the likelihood ratio difference test in applications of item response models. This study extended that research to the evaluation of dimensionality using the multidimensional random coefficients multinomial logit model (MRCMLM). Logistic regression analysis of simulated data reveal that sample size and test length have a large effect on the capacity of the LR difference test to correctly identify unidimensionality, with shorter tests and smaller sample sizes leading to smaller Type I error rates. Higher levels of simulated misfit resulted in fewer incorrect decisions than data with no or little misfit. However, Type I error rates indicate that the likelihood ratio difference test is not suitable under any of the simulated conditions for evaluating dimensionality in applications of the MRCMLM.
More Related Videos
08:13Using the Race Model Inequality to Quantify Behavioral Multisensory Integration Effects
Published on: May 10, 2019
09:00Author Spotlight: Validation of SICOLE-R for Assessing Cognitive and Reading Skills in Spanish-Speaking Children and Its Role in Personalized Education
Published on: August 16, 2024
Related Concept Videos
Friedman Two-way Analysis of Variance by Ranks
Test for Homogeneity
Spearman's Rank Correlation Test
Spearman's test calculates correlation by...
Ratio Level of Measurement
A set of data measured using the ratio scale takes care of the ratio problem and provides complete information. Ratio scale data are like interval scale data, except they have a zero point and ratios can be calculated....
Goodness-of-Fit Test
Expected Frequencies in Goodness-of-Fit Tests