Re: [R] exponential correlation?

[Spencer Graves]

     The "nlme" package has "corExp" for estimating the nuggett effect 
n and the range d for an exponential spatial correlation structure = n + 
(1-n)*exp(-r/d), where r = distance between two observations.  See 
library(nlme);  ?corExp, plus Pinheiro and Bates (2000) Mixed-Effects 
Models for S and S-Plus (Springer). 

     Is this what you want? 

     hope this helps. 
     spencer graves
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TRAMIER Blaise wrote:
Hello,
	I have been asked to perform a exponential correlation on a data set.
Unfortunately, i did not find any simple example on how to do that with R. 
If the correlation is significant, one asked me to also find the thresold 
of the acceleration slope.

Have any of you a little example or a good link to get me started?
Best regards
Blaise
 

--
Spencer Graves, PhD, Senior Development Engineer
O:  (408)938-4420;  mobile:  (408)655-4567
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