[R] non-stationary covariance
ripley at stats.ox.ac.uk
Wed Apr 3 11:47:13 CEST 2002
There are at least three R packages to do this, spatial, geoR and
sgeostat. Look at library(help=) for each.
On Wed, 3 Apr 2002, Lecca Paola wrote:
> Hi !
> Sorry for my ignorance. I have two questions:
> 1) which is in R the function to make a covariogram of spatial data ?
> 2) does anyone know if there exist the possibility in R of performing
> kriging with an arbitrary covariance function ?
Certainly. It's just linear algebra which R does fairly well (and I've
written code to do so in S long ago, when it was too slow on a 12Mb 20MHz
> If I have well understood the Krig procedure offers only three
> possibilities (expcov, gauscov and sphercov) that are the common models
> for stationary and isotropic processes.
surf.gls allows arbitrary stationary and isotropic processes, for example.
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272860 (secr)
Oxford OX1 3TG, UK Fax: +44 1865 272595
r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch
More information about the R-help