Re: AI-GEOSTATS: bad regression between predicted and measured

2003-10-14 Thread Russell Barbour
Dear Dr. Rocchini: Well, my first reaction is that R squared is not an appropriate measure for correlated data. Secondly, such a large area may well have an underlying trend which should be removed before kriging is attempted and lastly the number of observations seems very small if that is

Re: AI-GEOSTATS: bad regression between predicted and measured

2003-10-13 Thread Isobel Clark
Duccio There are many reasons why your interpolations may not be working. A few of these are: # you are beyond the range of influence of any distance relationship, that is you have too widely spaced sampling. # your data may have a skewed or other non-Gaussian distribution which makes both