[R-sig-Geo] determining values for nmax, nmin and maxdist

[Tim Peterson]

Hi Daniel,

I've never had much success with rules of thumb (eg variogram range). I 
suggest you look into more objective approaches - eg see paper below. 
When I've played with global methods similar to Abedini I've found that 
cross-validation errors (with and without replacement) show a search 
distance that gives a minimum error. Re local  search distance 
estimation (see Abedini), I suspect that for any moderate to large 
problem the computations becomes prohibitive.

M.J. Abedini, M. Nasseri, D.H. Burn, The use of a genetic 
algorithm-based search strategy in geostatistics: application to a set 
of anisotropic piezometric head data, Computers & Geosciences, Volume 
41, April 2012, Pages 136-146, ISSN 0098-3004, 
http://dx.doi.org/10.1016/j.cageo.2011.08.024

Cheers

Tim

On 07/02/2016 07:47 AM, Dan Turenne wrote:
> Hello listers,
>
>
> As part of the research I am doing I'm attempting to fit some kriging models, and I was wondering if there are any "rule of thumb" guidelines for selecting the values for the nmax, nmin and maxdist parameters?  Intuitively I would set maxdist equal to the range of the variogram but I'm not sure about the other parameters.  Any advice on this subject would be appreciated.
>
>
> Thanks,
>
>
> Daniel Turenne
>
> University of Manitoba
>
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>
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-- 
--------------------
Dr. Tim Peterson

The Department of Infrastructure Engineering
The University of Melbourne, 3010 Australia
T: +61 3 8344 9950 <tel:%2B61%203%208344%209950>, M: +61 0438 385 937 
<tel:%2B61%200438%20385%20937>

Dept. profile : 
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Google Scholar: 
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