Re: AI-GEOSTATS: stratifying the spatial domain on the basis of dependent variable

2009-01-12 Thread Cristiano Ballabio
Thanks everybody for the replies, Monica, indeeed, the first thing I did was to test the if distribution was a mix of samples from two populations. I did use the Mclust package in R, which gives a BIC score relative to the hypotesis that the samples are a mixture of n normal distributions,

AI-GEOSTATS: stratifying the spatial domain on the basis of dependent variable

2009-01-09 Thread Cristiano Ballabio
Dear All, I'm experiencing some doubt about the logic consistency of the procedure I'm following to analyse my data. The dataset I'm dealing with, comprises 360 sampling points; for each one of this points I have a measure of nitrate concentration in groundwater. What I'm trying to do is to

Re: AI-GEOSTATS: stratifying the spatial domain on the basis of dependent variable

2009-01-09 Thread seba
Hi Cristiano I think that you can try to use moving windows statistics to check if there are strong differences in variability and mean values among the eastern and southern part of the spatial domain (obviously trying to understand the processes behind these differences). Then, I guess that

Re: AI-GEOSTATS: stratifying the spatial domain on the basis of dependent variable

2009-01-09 Thread Monica Palaseanu-Lovejoy
Hi, I think that the first step is to make sure that your 2 different sample distributions really come from 2 different populations and they are not actually random samples of the same population. There are different mix-population analyses implemented in R, an open source software