Extended growth curve models with random-effects covariance structures

Abstract

This paper is concerned with profilc analysis of growth curves of several groups. Two extended growth curve models introduced by Verbyla and Venables (1988) are considered. The first is a growth curve model with covariates, which has a random-effects covariance structure based on a single response variable; the second is a multivariate growth curve model with parallel profiles, which has a multivariate random-effects covariance structure based on several response variables. Test statistics for testing hypotheses about mean parameters are suggested under the random-effects covariance structures.

Keywords:

• growth curve model
• random-effects covariance structure
• profile analysis
• null distribution
• likelihood ratio test