[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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