sill not reaching 1 in a climatological variogram
On 05/02/2013 06:30 PM, subash wrote:
Hi All, I constructed a climatological variogram using 'gstat' package in R at daily scale using 2 monsoon(JJAS) data. The *exponential* model was with variogram parameters nugget - 0.04243 psill - 0.96633 Range - 16.88 Km <http://r-sig-geo.2731867.n2.nabble.com/file/n7583465/climat_vario.png> I have couple of questions: (1) Why is the psill not reaching 1, when the each day rain has been normalized?
total sill, i.e. psill + nugget are supposed to approach the variance of the field; they seem to do so. I also believe that this only holds for the ergodic case, where you would make your spatial domain infinite.
(2) Why is there a dip in the variogram at 50Km?
I wouldn't see this as a structural property; consecutive sample variogram estimates are dependent as they share the same observations when forming pairs.
Your help will be highly appreciated. Thanks & Regards Subash -- View this message in context: http://r-sig-geo.2731867.n2.nabble.com/sill-not-reaching-1-in-a-climatological-variogram-tp7583465.html Sent from the R-sig-geo mailing list archive at Nabble.com.
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