Re: AI-GEOSTATS: Cross variogram
Digby That is the 'traditional' cross semi-variogram as discussed in Matheron's original work. Now also known as a co-located cross semi-variogram. There is a non-co-located cross semi-variogram which goes something like: gamma(h)=1/2N(h) SUMi,j(vi-uj)^2 which is always positive. However, you probably have to standardise u and v to get meaningful results (which you can't really do with skewed data). Noel Cressie has shown in a paper in Math Geol that a semi-variogram calculated on logarithms is the same generically as a general relative semi-variogram. I should think that conclusion probably holds for cross semi-variograms too. Calculating on logarithms is computationally simpler than calculating a relative semi-variogram. Isobel Clark http://uk.geocities.com/drisobelclark --- Digby Millikan [EMAIL PROTECTED] wrote: Hello everyone, The forumlea which I have obtained for the cross variogram is; gamma(h)=1/2N(h) SUMi,j(vi-vj)(ui-uj) Is it correct then that the product of the differences can be negative in cases. Digby __ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com -- * To post a message to the list, send it to [EMAIL PROTECTED] * As a general service to the users, please remember to post a summary of any useful responses to your questions. * To unsubscribe, send an email to [EMAIL PROTECTED] with no subject and unsubscribe ai-geostats followed by end on the next line in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list * Support to the list is provided at http://www.ai-geostats.org
AI-GEOSTATS: Novel Interpolation Method
To those who are interested in "interpolation" for any dimensions (1D, 2D, 3D,..). We have good news to you. To date, there are no existing publications regarding interpolation methods that can be deduced analytically and extended easily to arbitrary dimensions. In fact, there is no publication for interpolation greater than 5-dimension. Based on the standard Monte-Carlo method as well as the Dirac delta function, we are able to "derive" an interpolation formulation which is good in any dimension. Please check our site for more info and demo at: http://www.fanginc.com/main.htm Our interpolation method can also be used in non-Cartesian space, e.g. spherical and cylindrical 3D. Feedback is welcome. Dr. Ben Fang FANG, INC. [EMAIL PROTECTED]
