Back to Search Start Over

A copula-based approach to joint modelling of multiple longitudinal responses with multimodal structures.

Authors :
Mahdiyeh, Zahra
Kazemi, Iraj
Verbeke, Geert
Source :
Statistical Modelling: An International Journal. Aug2022, Vol. 22 Issue 4, p327-348. 22p.
Publication Year :
2022

Abstract

This article introduces a flexible modelling strategy to extend the familiar mixed-effects models for analysing longitudinal responses in the multivariate setting. By initiating a flexible multivariate multimodal distribution, this strategy relaxes the imposed normality assumption of related random-effects. We use copulas to construct a multimodal form of elliptical distributions. It can deal with the multimodality of responses and the non-linearity of dependence structure. Moreover, the proposed model can flexibly accommodate clustered subject-effects for multiple longitudinal measurements. It is much useful when several subpopulations exist but cannot be directly identifiable. Since the implied marginal distribution is not in the closed form, to approximate the associated likelihood functions, we suggest a computational methodology based on the Gauss-Hermite quadrature that consequently enables us to implement standard optimization techniques. We conduct a simulation study to highlight the main properties of the theoretical part and make a comparison with regular mixture distributions. Results confirm that the new strategy deserves to receive attention in practice. We illustrate the usefulness of our model by the analysis of a real-life dataset taken from a low back pain study. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
1471082X
Volume :
22
Issue :
4
Database :
Academic Search Index
Journal :
Statistical Modelling: An International Journal
Publication Type :
Academic Journal
Accession number :
158843281
Full Text :
https://doi.org/10.1177/1471082X20967168