Reminder...
UNIVERSITY OF HERTFORDSHIRE STATISTICS SEMINAR SERIES
www.herts.ac.uk/business/staff_public/nhspencer_public/seminars
Sponsored by Department of Statistics, Economics, Accounting and
Management Systems, Business School, University of Hertfordshire.
Wednesday 14th May 2003, 2:30pm, room C408, Hatfield campus
Andrew Thomson (Imperial College)
Title: "The Use and Limitations of Bayesian Spatial Smoothers In
Disease Mapping"
Abstract:
"Disease mapping can be thought of as the estimation and presentation
of spatial summary measures of health outcomes. When the expected
count in areas is small, raw estimates are poor estimates of the
underlying risk. To overcome this, these risks are modelled via a
hierarchical Bayesian model that imposes a priori a certain spatial
structure. This allows the 'borrowing of strength' from the neighbours
of an area to provide more robust results.
One of the most commonly used models in disease mapping is the
Conditional Autoregressive Model of Besag et al that can easily be
implemented in the BUGS software. A modified model based upon the
double exponential distribution is also used, but the main problem
with both of these is one of over-smoothing. In order to address this,
alternative models such as the Hidden Markov Reversible Jump model of
Richardson & Green have been developed.
In the first part of the talk, these models will be reviewed. In the
second, results from a recent full-scale simulation study of the
performance of models will be presented. The parameters of the
simulation included differing expected counts, different size of the
risk and a different spatial layout of the clusters."
For further information regarding location, parking, etc.,
please contact Neil Spencer (details below).
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Dr Neil H. Spencer
Senior Lecturer in Statistics
Head of Statistical Services and Consultancy Unit
Statistical Services and Consultancy Unit Address:
Lindop Building, University of Hertfordshire, Hatfield Campus,
College Lane, Hatfield, AL10 9AB, U.K.
Telephone: +44 (0) 1707 284366
Fax: +44 (0) 1707 284799
E-mail: [log in to unmask]
WWW: http://www.herts.ac.uk/business/centres/sscu
Departmental Address:
Dept. of Statistics, Economics, Accounting and Management Systems,
Business School, University of Hertfordshire, Hertford Campus,
Mangrove Road, Hertford, SG13 8QF, U.K.
Telephone: +44 (0) 1707 285529
Fax: +44 (0) 1707 285489
E-mail: [log in to unmask]
WWW: http://www.herts.ac.uk/business/staff_public/nhspencer_public
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