AI-GEOSTATS: Nugget effect and Surfer 8
- Has anyone encountered a problem with Surfer 8 and its settings for what
concerns the search strategy and its impact on the nugget effect?
If you set the search option to "No Search" during the gridding step, and if
you set any value for the nugget effect (the error variance here only, I kept
the micro variance equal to zero), the cross-validation function of Surfer
will give you always the same statistics for the residuals!
However, if you set a large radius of search in the search option (as a
result, the search strategy is the same as if you were using the "no search"
option), then only one can see the impact of the nugget effect on the results.
I have just asked the software developers for more info about this matter but
was wondering if my approach was wrong or if this is what a believe a nasty
The output maps, however, seem to deal properly with the nugget effect. I
presume that the cross-validation algorithm only is not correct.
Any feedback would be appreciated.
Have a nice week-end !
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