Geoscience Reference
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ylim([0 200])
title('Kriging Variance')
xlabel('x-Coordinates')
ylabel('y-Coordinates')
colormap(jet)
colorbar
hold on
and we overlay the sampling positions:
plot(x,y,'ok')
hold off
h e kriged values are shown in Figure 7.22 a. h e kriging variance depends
only on the distance from the observations and not on the observed values
(Fig. 7.22 b). Kriging reproduces the population mean when observations
are beyond the range of the variogram; at the same time, the kriging variance
increases (lower right corner of the maps in Figure 7.22). h e kriging
variance can be used as a criterion to improve sampling design and it is
needed for back-transformation in lognormal kriging. Back-transformation
for lognormal kriging is achieved by:
a
b
Fig. 7.22
Values interpolated on a regular grid by ordinary point kriging using
a
an
exponential variogram model, and
b
the kriging variance as a function of the distance from
the observation (empty circles).
