Russell, If you have time to get to your library there is a book "Geostatistical Ore Reserve Estimation" 1977 M.David although related to geostatistics for mining this book is written by a renowned geostatistician and has an excellent diagrammatic representation of trend, drift and stationarity Fig. 188, 189 pp267 which relates to your question.
Hope this is of some help. Thanks, Regards Digby Millikan B.Eng Geolite Mining Systems U4/16 First Ave., Payneham South SA 5070 Australia. Ph: +61 8 84312974 [EMAIL PROTECTED] http://www.users.on.net/digbym -- * 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
