Intraclass correlation coefficients (ICC) are employed in a wide range of behavioral, biomedical, psychosocial, and health care related research for assessing reliability of continuous outcomes. The linear mixed-effects model (LMM) is the most popular approach for inference about the ICC....

Outliers are commonly observed in psychosocial research, generally resulting in biased estimates when comparing group differences using popular mean-based models such as the analysis of variance model. Rank-based methods such as the popular Mann-Whitney-Wilcoxon (MWW) rank sum test are more...

The generalized estimating equations (GEEs) and generalized linear mixed-effects model (GLMM) are the two most popular paradigms to extend models for cross-sectional data to a longitudinal setting. Although the two approaches yield well-interpreted models for continuous outcomes, it is quite a...

Poisson log-linear regression is a popular model for count responses. We examine two popular extensions of this model -- the generalized estimating equations (GEE) and the generalized linear mixed-effects model (GLMM) -- to longitudinal data analysis and complement the existing literature on...