[R-sig-Geo] gstat Cross validation IDW vs ordinary kriging interpolation

2014-05-15 Thread Moshood Agba Bakare
Dear All, I used the script below to create interpolation surface using ordinary kriging and inverse distance weighting approach.Could anyone guide me on how to cross validate the two interpolation methods to identify the optimal? I intend to obtain the diagnostic statistics such mse, rmse and

Re: [R-sig-Geo] Still a bug when converting from tess to spatial polygon (sp) format?

2014-05-15 Thread Roger Bivand
Hi Fabricio, Thanks, but the use case I was considering was that a tess object itself includes marks of some kind that are lost in coercion. This is not the case here, so it is very much better that users actually learn to use the objects provided. The minimal incantation to go from a

[R-sig-Geo] Local spacetime kriging

2014-05-15 Thread Roelof Coster
Hi, The krigeST function has a 'nmax' parameter that sets the maximum number of neighbouring observations to be used in the prediction. However, the help for this function states that it does not support kriging in a local neighbourhood. So, is this just a mistake in the help? Also, in case

Re: [R-sig-Geo] Local spacetime kriging

2014-05-15 Thread Benedikt Gräler
On 15.05.2014 15:47, Edzer Pebesma wrote: On 05/15/2014 10:58 AM, Roelof Coster wrote: Also, in case kriging in a neighbourhood is possible, how does the function determine this neighbourhood? How is distance in space compared to distance in time? It uses

[R-sig-Geo] R: Regression Kriging cross validation

2014-05-15 Thread Michele Fiori
Thank you for your kind reply therefore as I have used the Osl method for regression, my result will never match the universal kriging; However, in order to validate my method, I'm trying to implement in the script a calculation loop witch runs n times (the number of stations) regression + kriging

[R-sig-Geo] error in readShapePoly

2014-05-15 Thread Mahbubeh Parsaeian
Dear all I have a shape file of UK. I have used it serveral times before. But now when I want to use this shapefile the following error will apear. shp-readShapePoly(GreaterLondon_ward) Error in read.shape(filen = fn, verbose = verbose, repair = repair) :   File size and implied file size