What happens in kigeTg doesn't look that hard. Have you tried? Ebrahim Jahanshiri wrote: > Thank you very much. > However I found no couterpart for that in cokriging. Is there any way to do > that manually? I mean to get "m" manually? > > On Mon, Mar 1, 2010 at 8:26 PM, Edzer Pebesma <[email protected] >> wrote: > >> Ebrahim Jahanshiri wrote: >> >>> I am wondering if there is any function or option to back-transform the >>> result of the lognormal kriging in gstat yet. >>> >>> >> You can use krigeTg, which does trans-Gaussian kriging for all Box-Cox >> transforms; passing it a lambda parameter with value 0, log-normal kriging >> is used. Pls look at the examples, the back-transformed values have funny >> names like var1TG.pred. >> >> The whole think has been implemented for ordinary kriging only; if someone >> can point me out a source that describes how to do this for universal / >> external drift kriging, I'd be happy to look into how to implement it. >> >>> Although for simple kriging it is fairly straight forward, that is, it is >>> >>> possible to do back-transform using the vector of predicted values and >>> kriging variances, but for ordinary kriging, it might be difficult because >>> we dont have lagrange multiplier (according to my web help search) to do >>> the >>> back-transformation. I am wondering if there has been any advancement in >>> that matter? >>> >>> thank you >>> >>> [[alternative HTML version deleted]] >>> >>> _______________________________________________ >>> R-sig-Geo mailing list >>> [email protected] >>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo >>> >>> >> -- >> Edzer Pebesma >> Institute for Geoinformatics (ifgi), University of Münster Weseler Straße >> 253, 48151 Münster, Germany. Phone: +49 251 8333081, Fax: +49 251 8339763 >> http://ifgi.uni-muenster.de http://www.52north.org/geostatistics >> [email protected] >> >> >
-- Edzer Pebesma Institute for Geoinformatics (ifgi), University of Münster Weseler Straße 253, 48151 Münster, Germany. Phone: +49 251 8333081, Fax: +49 251 8339763 http://ifgi.uni-muenster.de http://www.52north.org/geostatistics [email protected] _______________________________________________ R-sig-Geo mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-geo
