STK_EXAMPLE_KB06  Ordinary kriging VS kriging with a linear trend

 The same dataset is analyzed using two variants of kriging.

 The left panel shows the result of ordinary kriging, in other words,  Gaussian
 process interpolation  assuming a constant (but unknown) mean. The right panel
 shows the result of adding a linear trend in the mean of the Gaussian process.

 The difference with the left plot is clear in extrapolation: the first predic-
 tor exhibits a  "mean reverting"  behaviour,  while the second one captures an
 increasing trend in the data.