Dear Pierre,

You mentioned that the nugget effect represents
measurement errors or small-scale variability in the
field. How to differentiate between both of them?

Last year I was studying about factorial kriging.
Actually on that time I wanted to use factorial
kriging to filter the nugget variance. I assumed that
my nugget variance only represented small-scale
variability, because I was sure (I already checked)
that my data set did not have any measurement errors. 

I also was surprised when I got the estimation result.
Beforehand I guessed that the estimation result will
be more precise as I excluded the nugget variance, but
actually the result showed the contrary. When I
plotted the estimated versus real values, the
correlation coefficient was much less (compared to
include the nugget variance in estimation).
 
Thank you.


Nur Heriawan
------------
Earth Resources Exploration Research Group
Institut Teknologi Bandung
Indonesia


--- Pierre Goovaerts <[EMAIL PROTECTED]> wrote:

> Hi Niklas,
>  
> This is a very good question; in fact one of the
> participants to my last short course
> asked the same question since he was using ARCview
> with the option
> "nugget effect excluded"  and was surprised to see
> that his observations were
> not honored by the kriging predictions. 

M. Nur Heriawan
http://www.mining.itb.ac.id/heriawan

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 

* By using the ai-geostats mailing list you agree to follow its rules 
( see http://www.ai-geostats.org/help_ai-geostats.htm )

* To unsubscribe to ai-geostats, send the following in the subject or in the 
body (plain text format) of an email message to [EMAIL PROTECTED]

Signoff ai-geostats

Reply via email to