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Department of Statistics, The Ohio State University
Statistics and Biostatistics Colloquium Series
Estimating a Non-Stationary Spatial Structure Using Simulated
Annealing
Olivier Perrin
The Ohio State University
3:30PM - Thursday, January 8, 2004
Room 170, Eighteenth Avenue Bldg. (EA 170)
ABSTRACT
During the past decade, a useful model for non-stationary random
fields has been developed. This consists of reducing the random
field of interest to isotropy via a bijective bi-continuous
deformation of the index space. Then the problem consists of
estimating this space deformation together with the isotropic
correlation in the deformed index space. We propose to estimate both
this space deformation and this isotropic correlation using a
constrained continuous version of simulated annealing based on the
Metropolis-Hastings algorithm. This method provides a non-parametric
estimation of the deformation that has the required property to be
bijective; previous non-parametric methods did not guarantee this
property. We also give one idea of how spatial prediction should
proceed in the new coordinate space. We illustrate our work with an
example based on a precipitation dataset.
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