Re: [R-sig-Geo] Collinearity test
Hello Maurizio, Mostly Variance Inflation Factor (VIF) criteria is applied, which is avaiable is all standard R-packages that offer performing regression. Sincerely Imran Muhammad Imran On Wednesday, November 13, 2013 11:00 AM, Maurizio Marchi mauriziomarch...@gmail.com wrote: Hallo everybody, I'm working with Species Distibution Models to predict the potential distribution of a forest specie. I use WorldClim raster data for Italy and before running SDMs algorithm I would like to test the collineariy between factors to eliminate redundancy of data. My question in: is there a package that can be used to Test collinearity between factors of a raster stack (worldclim biovariables)? Thanks, -- Maurizio Marchi, Ph.D student Forestry Research Centre (Arezzo, IT) ID skype: maurizioxyz *Ubuntu 12.04 (Precise Pangolin)* [[alternative HTML version deleted]] ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo [[alternative HTML version deleted]] ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
[R-sig-Geo] How to perform K-fold cross validation for the spdep spautolm (CAR) and spgwr GWR models
hi people, My objective is to perform K-fold cross validation for the spdep spautolm (CAR) and spgwr GWR model objects, to evaluate the models predictive performance (using model predictions and sampled data). For this, I have been searching for some functions/packages. Any idea/R-code/tutorial? The R-packages Design and DAAG only take 'lm' object to perform K-fold CV. With krige.cv I can perform the CV for the CAR and GWR residuals, but would that serve the objective? Thanks in advance! -Imran ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
[R-sig-Geo] K-fold cross validation for the spdep spautolm (CAR) and spgwr GWR models?
hi people, My objective is to perform K-fold cross validation for the spdep spautolm (CAR) and spgwr GWR model objects, to evaluate the models predictive performance (using model predictions and sampled data). For this, I have been searching for some functions/packages. Any idea/R-code/tutorial? The R-packages Design and DAAG only take 'lm' object to perform K-fold CV. With krige.cv I can perform the CV for the CAR and GWR residuals, but would that serve the objective? Thanks in advance! -Imran ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
[R-sig-Geo] OK smoothing effect
Hi list members, It is wekk known that OK tends to smooth the spatial variation of a variable; in particular they overestimate small values and underestimate large values. What should I percieve if I am getting a revserse effect after krging i.e. underestimated small values and overestimated large values. regards, Imran ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
[R-sig-Geo] How to find GWR prediction variance as a measure of uncertainty?
Hi list fellows, Do someone have any idea to calculate the standard deviation of GWR predictions (prediction variances), similary as we calculate with the sqrt of prediction variance provided by kriging? Would be thankful for any help? Best regards Imran ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
[R-sig-Geo] How to find GWR prediction variance as a measure of uncertainty?
Hello, Can anybody confirm if the prediction variance of GWR calculated as sqrt(var(mod.gwr$SDF$pred.se)) is right? Thanks and regards, Muhammad Imran ___ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
