[R-sig-Geo] variogram maps / newbie

[Facundo Muñoz]

Hi Pedro,

perhaps if you could paste some sample code, we could talk about 
something more concrete...

I understand that you were able to plot empirical variograms using both 
variog (geoR) and variogram (gstat).

In both of them you control the maximum distance:
   in geoR: using max.dist, or uvec which also allows to define the bins
   in gstat : with cutoff

and the binning: uvec (geoR) and width (gstat).

In despite of this, they will not plot the same empirical variograms 
even if you define the same bins and maximum distance, since variog 
(geoR) places the estimates exactly at the bins limits, while variogram 
(gstat) calculates the mean of the distances of the pairs of 
observations used for each estimate, and places the estimate at that 
precise distance. (Ajjj, i'm sure it can be said better)

In sum: even if you manage to make them calculate the same estimates 
with the same pairs of observations each, you will have the same 
estimates but located at (more or less slightly) different ordinates.

Reagards
      Facundo.-

Pedro Mardones escribió:
> Dear all;
> Does anyone knows how to obtain a variogram map using the package geoR?
> I was able to obtain these plots using the gstat package but the
> results form the variog function are different to those from variogram
> function in gstat (I guess that has something to do with the bin and
> maximum distance but not sure)
> Suggestions will be appreciated
> PM