Please note the unusual starting time: 17:00pm.
MANCHESTER CENTRE FOR STATISTICAL SCIENCE
SEMINARS (2002-03)
Date: Wednesday 19 March 2003 at 17:00pm
Venue: Room 2.14, Maths Tower, University of Manchester
Speaker: Professor G. MacKenzie, Keele University
Title: Modelling Covariance in Longitudinal Studies
Abstract:
The idea that in longitudinal data analysis (LDA) the mean
might be modelled as a function of time and baseline
covariates ( eg , the treatment indicator in an RCT)
is well established. The idea that the second parameter
in the model, the covariance, might be modelled is
also well-established, but that it might be modelled
in a regression. Similarly to the mean is rather new. A
third idea, that selection of the optimal pair of parameters
should be "joint", renders much current practice
redundant.
We review the key concepts behind joint mean-covariance
modelling in LDA, when the response is continuous,
develop an augmented regression model for the mean
and covariance and present a new algorithm for finding
the optimal model in the joint mean-covariance model
space.
NB: The talk is based on joint work with Dr. Jianxin Pan,
Department of Mathematics, Manchester University.
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Dr Jianxin Pan
Department of Mathematics
The University of Manchester
Oxford Road, Manchester
M13 9PL
Tel: 0161-27-55864
Fax: 0161-27-55819
Email: [log in to unmask]
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