Dear All, Thanks for the replies from Isobel Clark and Jan Merks that have partly answered my questions.
For the calculation of statistics of a data set, there are two concepts that need to be considered: description or estimation. Suggested methods for calculation of "mean" include "optimal weighted average" and "count-weighted average". Suggested methods for calculation of "variance" include "dispersion variance", "sill" of a variogram and "mathematical statistics". However, it seems that all of these are still under discussion. Meanwhile, more comments and suggestions are welcome. Best regards, Chaosheng Zhang ----- Original Message ----- From: "Chaosheng Zhang" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Thursday, May 25, 2006 9:12 AM Subject: Effects of spatial autocorrelation on descriptive statistics > Move of the list to [EMAIL PROTECTED] All, > > I'm looking for answers to effects of spatial autocorrelation on > conventional descriptive statistics. More specifically, any comments on the > following statements? > > 1. "Spatially correlated data provide redundant information for the > calculation of mean"; > > 2. "In the presence of spatially correlated data, would a dispersion > variance . be the proper calculation for the measure of variance?" > > Best regards, > > Chaosheng Zhang > ------------------ > Dr. Chaosheng Zhang > Lecturer in GIS > Department of Geography > National University of Ireland, Galway > IRELAND > Tel: +353-91-492375 > Fax: +353-91-495505 > E-mail: [EMAIL PROTECTED] > Web1: www.nuigalway.ie/geography/zhang.html > Web2: www.nuigalway.ie/geography/gis > > > + + To post a message to the list, send it to [email protected] + To unsubscribe, send email to majordomo@ jrc.it with no subject and "unsubscribe ai-geostats" in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
