Royal Statistical Society
Statistical Computing Section Meetings
Half day meeting on Computerised Spatial Analysis
A joint meeting with the GAS and the Sheffield Local Group
"Spatio-temporal modelling of zooplankton species in the North Atlantic"
Simon Wood (University of Bath) and W. Horbelt, D.C. Speirs, M.R. Heath and W.S.C. Gurney
Synopsis: Calanus finmarchicus is the dominant zooplankton species over much of the
North Atlantic. It has an unusual life-cycle involving overwintering in
very deep waters at very cold temperatures and then re-ascending to breed
in the spring. Because of the considerable distances that individual
calanus are transported during their lives, calanus population dynamics
can only be properly understood at the scale of the whole North Atlantic.
This involves the formulation of physically driven spatially explicit
population dynamic models describing the whole north atlantic population.
However, given the complexity of the calanus life-cycle, key model
parameters can only be estimated by treating this complex model as a
statistical model and fitting it to data on calanus abundance. This talk
describes an approach to doing this, involving a (parallelized) hybrid of
finite differencing and autodifferentiation to obtain derivatives of the
model predictions w.r.t. the parameters, coupled with a modified
Gauss-Newton fitting method.
"Computational Methods in Spatial Epidemiology"
Virgilio Gomez-Rubio and Nicky Best (Dept. of Epidemiology and Public Health, Imperial College London)
Synopsis: The talk will describe some of the state-of-the-art models employed in
spatial statistics and, specifically, in spatial epidemiology. A brief
introduction on how WinBugs can be used to fit spatial models and
associated computational challenges will be given. This will be followed
by a description of how GeoBugs can help with the definition of the
spatial models and with the display of results in a map. Finally, we
will show how WinBugs can be linked to the R statistical language for
initial data management or representation and exploitation of WinBUGS
results by R's enhanced plotting capabilities. This part will include
descriptions of recent packages developed by the R user community.
"Adaptive Sampling for Automated Soil Mapping"
Ben Marchant (Rothamsted Research, Harpenden
)
Synopsis: A major problem for management of within-field variation is obtaining
adequate information on the variations of important variables at
acceptable cost. If soil properties are to be mapped with adequate
precision, then the sampling intensity needed will differ between
fields. Therefore farmers and agronomists run the risk of completing a
survey then finding that they have substantially over-sampled and so
wasted effort, or that they are not able to produce a reasonable map
from the data because they are too sparse. In this talk we describe the
development of adaptive methods for designing sample schemes which are
suited to the property being measured when we start with little or no
information on the spatial variability of the variable.
"Statistical Archaeology"
Speaker to be confirmed ()
Synopsis: To follow
Date & Time
Wednesday 15th March 2006, at 2:00-4:30 pm
Place
Hicks Building (1st floor/floor E), Hounsfield Road, Sheffield S3 7RH
