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[SOLVED] uniform conditionning and change of support

PostPosted: Thu Sep 19, 2013 9:29 am
by Maxime Beauchamp
Hi,

You probably understood during the "Journées de Géostatistiques 2013", that one of my interest is the estimation of probability of exceeding limit value in air quality. I am interested in uniform conditionning and so, I am wondering if methods for calculation of the change of support point-block coefficient is implemented in RGeoS, such as Block Partition or Block Discretization methods in Isatis.

Thanks,

Maxime Beauchamp

Re: uniform conditionning and change of support

PostPosted: Thu Sep 19, 2013 1:56 pm
by Nicolas Desassis
Hi,

if you want to use the Discret Gaussian Model of Emery, the change of support coefficient r can be determined easily by averaging
the covariance function of the Gaussian random function on your polygon and taking the square root.
It can be done with RGeoS with the following sequence of instructions (where p is here a simple square of size 1 and the model an exponentiel covariance with practical range 1) :


model=model.create(vartype=melem.name(2),range=1)
p=polygon.create(c(0,0,1,1),c(0,1,1,0))
plot(p)
r=sqrt(model.cvv(p,model))


I hope it is useful.

Regards,

Nicolas

Re: uniform conditionning and change of support

PostPosted: Thu Sep 19, 2013 2:55 pm
by Maxime Beauchamp
Thanks a lot !

Maxime