Functions for the interpolation of large spatial datasets.
This pacakge uses a "fixed rank Kriging" approach using a large
number of basis functions and provides spatial estimates that
are comparable to standard families of covariance functions and
estimates that are close to interpolating the observations (a
small nugget variance.) The covariance model for this method
approximates the Matern but also allows for a multi-resolution
model and supports efficient computation of the profile
likelihood for estimating covariance parameters. Also included
are generic methods for prediction and plotting of the
estimated surface.