[R-sig-Geo] kriging

Dave Depew ddepew at sciborg.uwaterloo.ca
Tue Jun 17 14:57:07 CEST 2008

Thanks Tom,
I've been able to fit a polynomial function to the data quite well. The 
residuals are behaving (i.e normal distribution and no skewness of 
variance). I'm assuming this means that I could krige the residuals 
(Ordinary K?) and then add the trend back to the predicted residual 
grid? I realize that I won't be able to place confidence limits on the 
predictions, but the data is primarily to show that we might be able to 
use GPS hydroacoustic signals to show macrophyte cover and estimate the 
standing crop. I'm still a newbie when it comes to the theory involved 
in kriging, but I think I am familiar with the basics...the variogram of 
the residuals is a nice spherical model (i.e. it reaches a sill about 
50% or so above the nugget, and there is little scatter). I am assuming 
(perhaps wrongly) that the residuals may be modelled with a variogram 
and then kriged...

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