Loading ...
Sorry, an error occurred while loading the content.

Re: [AI-GEOSTATS: Universal Kriging in ArcInfo]

Expand Messages
  • Gregoire Dubois
    Dear Jason, I saw few replies to your question and I can imagine you are a bit lost with these technical terms that are not documented in Arc/Info s manual.
    Message 1 of 1 , Jan 17, 2001
    • 0 Attachment
      Dear Jason,

      I saw few replies to your question and I can imagine you are
      a bit lost with these technical terms that are not documented in
      Arc/Info's manual.

      Versions younger than Arc/Info 8.0 (which has a brand new geostatistical
      module) are almost useless for what concerns geostatistics.
      More than the estimation algorithm (ordinary
      kriging, universal kriging, etc.), it is the analysis and the
      modelisation of the spatial correlation which is essential. Since
      you can't properly make a decent semivariogram analysis
      and since the fitting of the semivariogram is automatic (almost any
      geostatistician will tell you to fit your model manually or at least to
      have a full control on the parameters you select) in Arc/Info 7, you can
      almost forget it ! Three years ago I developed in AML an interface between
      UNCERT (see my AI-GEOSTATS web pages for more info) and Arc/Info 7.0. There
      is unfortunately nothing left from the code since I left the
      place where I developed it but I'm sure many people on the list
      did something similar (with UNCERT, Gstat, GSLIB or the UNIX version of GeoEas
      for exemple).

      I'm sorry for the bad news but making a spatial interpolation, especially
      when you plan to use geostatistical methods, requires some experience from
      the users (and this is a radiobiologist that is talking, not a statistician)

      Hope this helps a bit,

      Gregoire

      PS: may I suggest you to download Geoeas (+ manual) and play around with the
      semivariograms to better realise how limited the functions are in
      Arc/Info 7.

      Jason Sawle <j.sawle57@...> wrote:
      > Hello
      >
      > This is my first time on the list and I hope this question is going to
      > the right place. My appologies if not.
      >
      > I am using Arc/Info 7.2.1 on an NT workstation.
      > With GRID I am using linear universal kriging to produce maps of heavy
      > metal concentration from 127 sample points.
      >
      > Could anyone tell me what c0 and b mean. These appear at the start of
      > the interpolation proceedure. I have values of 0 and 11580.591
      > respectively and I am unsure of what they imply about this method.
      >
      > Thanks for your time with this.
      >
      > Jason Sawle
      >
      > ###############################################################
      > Department of Geography
      > Canterbury Christ Church University College
      > North Holmes Road,
      > Canterbury, Tel: 01227 782337
      > Kent, Fax: 01227 767531
      > CT1 1QU, email: j.sawle57@...
      > United Kingdom http://www.cant.ac.uk
      >
      >
      > --
      > * To post a message to the list, send it to ai-geostats@...
      > * 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 majordomo@... 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


      Gregoire Dubois
      Institute of Mineralogy and Petrography
      Dept. of Earth Sciences
      University of Lausanne
      Switzerland

      http://www.ai-geostats.org

      ____________________________________________________________________
      Get free email and a permanent address at http://www.netaddress.com/?N=1

      --
      * To post a message to the list, send it to ai-geostats@...
      * 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 majordomo@... 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
    Your message has been successfully submitted and would be delivered to recipients shortly.