Maurizio,
a suggestion in order to use field-based geostatistics is that you define a conceptual variable X(s), where s=(s1,s2) is the location, representing the density of industries per using area. Then convert your data points to density values for some aggregation areas of your choice (these aggregation areas can be counties, departements, etc.). Then you can perform a geostatistical analysis of your density data. Note that this approach involves the appreciation of the spatial scale you are using (i.e. the size of the aggregation area you have selected). This is sometimes referred to as change of support in Geostatistics, the modifiable area unit problem (MAUP) for geographers and GIS applications, or the multiscale approach for the Bayesian Maximum Entropy (BME) theory. I can give you some reference to the latter if you wish. If you have access to MATLAB I can suggest the BMElib geostatistical package for analysis of space/time data ( http://www.unc.edu/depts/case/BMELIB/ ). Cheers, Marc Marc Serre, PhD Assistant Professor Center for the Advanced Study of the Environment (CASE) Department of Environmental Sciences and Engineering (DESE) The University of North Carolina at Chapel Hill CB 7431, 104 Rosenau Hall Chapel Hill, NC 27599-7431, USA e-mail: [EMAIL PROTECTED] phone: 919-966-1173 / 7014 fax: 919-966-7911 homepage: http://www.unc.edu/~mserre/ESEhome.html BMElib: http://www.unc.edu/depts/case/BMELIB/ Temporal GIS book: http://www.unc.edu/depts/case/BMELIB/TGISflyer2.htm ----- Original Message ----- From: "Maurizio Trevisani" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Friday, August 16, 2002 6:51 AM Subject: AI-GEOSTATS: Analysis of the distribution of points Could you give some URL to find documentation about ways to perform a sort of clustering of my geogrpahical data? I have several points (X,Y coords) corresponding to industries which produce wastes. I have, for each industry, a code corresponding to the type of industry, then several codes corresponding to the types of waste produced, with the corresponding quantity in tons. The number of such points is about 30.000, corresponding to about 120.000 combination industry-code of type of waste produced (each year). These industries are georeferenced, and I would like to explicitate the distribution of the type of industries and of the type of waste produced all over the country, recognizing significative groupings of such data. I think I could explore such data by means of geostatistical analysis and clustering techniques. Thank you, Maurizio Trevisani ******************************************************************** Maurizio Trevisani Sistema Informativo Ambientale della Regione Toscana - SIRA Agenzia per la Protezione dell'Ambiente della Toscana - ARPAT -- * 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 -- * 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
