1. Re: default value for cutoff in gstat variogram()

Hi
My 2 cents here.

I agree with Edzer that from statistical point of view there is not much 
point in compare this.
However the software implementation and checking can benefit from it.

Let me try to remember a few possible relevant points for the diferences:

1. the values in the x-axis : some will average distance values while 
others will take the mid point of the classes intervals (as done, for 
instence in histograms)

2. How to deal with interval borders (<= ou <, >= or >= )

3. How to deal with coincident locations

4. How the maximim distance for the variogram is defined

5. How to deal with NA's in some distance classes and minimum number of 
pairs

The packages will have different default options (maybe not aways clearly 
documented).
A commom exemple run using all packages would be welcome, and this should 
include not only geoR and gstat but also the opthers.
We only have to bear in mind that the choice of empirical variograms will 
aways be subjective, according to the options defined by the user.

Best
P.J.

1. Re: default value for cutoff in gstat variogram()

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