You might consider setting your problem up as a GLM/GAM. These use splines to to create a spatially smooth conditional mean surface. You can find examples of this in:
Waller and Gotway. "Applied Spatial Statistics for Public Health Data" and Wood. "Generalized Additive Models: An introduction with R" The latter also serves as a comprehensive guide to the mgcv package. However, since these create smooth surfaces (and if you do not have spatially discontinuous covariate effects, you didn't mention this), I wouldn't expect the exact results to be that different from those obtained at the nearest raster cell. Good luck, Nicholas Nicholas N. Nagle, Assistant Professor University of Colorado Department of Geography UCB 260, Guggenheim 110 Boulder, CO 80309-0260 phone: 303-492-4794 _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo
