Dear Chaosheng, > Thanks. I think the sampling density is good enough to reveal the spatial > structure, and the extreme samples are located within the "hot spots". The > problem is that the few values are still extremely high within the "hot > spots". This may be what the "nugget effect" means. > > I'm just wondering if these few extreme values should really be > "discarded"/ > "censored" or replaced. However, this could get some criticism as they may > be "real".
Is it possible, in your opinion, to model your variogram excluding those few extremes data and after to krige all data, included the extremes values? In this way, probably, you loose some spatial information concerning the variability of your data but you could obtain a more reliable picture of the "background" values. It depends from what you are asking to your data. What you, or somebody else, think about? regards Claudio ---------------------------------------------------------------------------- ----------------------------- Claudio Cocheo Fondazione Salvatore Maugeri - IRCCS Centro di Ricerche Ambientali via Svizzera, 16 I 35127 - Padova ph. (39) 0498064511 fax (39) 0498064555 mailto:[EMAIL PROTECTED] website: http://www.fsm.it -- * 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