A comparison of methods for estimating the random effects distribution of a linear mixed model

This article reviews various recently suggested approaches to estimate the random effects distribution in a linear mixed model, i.e. (1) the smoothing by roughening approach of Shen and Louis, 1 (2) the semi-non-parametric approach of Zhang and Davidian, 2 (3) the heterogeneity model of Verbeke and Lesaffre 3 and (4) a flexible approach of Ghidey et al. 4 These four approaches are compared via an extensive simulation study. We conclude that for...