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GEOSTATS: Re:Indicator Variograms - spatial correlation

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  • Yoshiro Nagao
    My problem seems to be same with the captioned one: We collected several insect species(A,B,C,D...) at sampling locations. Species A and B are negatively
    Message 1 of 3 , Apr 14, 1998
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      My problem seems to be same with the captioned one:

      We collected several insect species(A,B,C,D...) at sampling locations.

      Species A and B are negatively correlated in number at each the location.

      However, when I make a interpolated picture by inverse distance weighting,
      the density picture for A and B are nearly similar and are overlapped.
      ( I made the programme.)

      I concluded that species A and B are in competition in micro habitat,
      but their macro habitat are rather same.

      Actually A and B are near on their phylogenic tree.

      How can I geo-statistically show such a scale dependent
      spatial correlation?

      "Variogram" is the suitable method?

      It would be appreciated if a good book on this matter is
      recommended.

      "Steve Friedman" <friedman@...> sama said:
      >I'm working with a very large regional analysis of presettlement vegetation
      >patterns using General Land Office records. This data set is a point base
      >system. Each point consists of from 1 - 4 entries for a tree species present
      >at that location, absence data is not included in the data collection process.
      >
      >I'd like to model the presence of each species using indicator variograms for
      >comparisons between the species and secondly to compare results from
      >spatial autocorrelation for nominal data.
      >
      >My questions:
      >1. Where can I find software applications for indicator variograms?
      >
      >2. What is the relationship between indicator variograms and nominal
      > spatial autocorrelation? My assumption is that the techniques should
      > produce similar results. Am I correct?

      Nagao Yoshiro
      International Centre for Medical Research
      Kobe University
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    • Pierre Goovaerts
      Indicator semivariograms are indeed the perfect tools for detecting the presence of scale-dependent correlations between categories. A good reference for
      Message 2 of 3 , Apr 15, 1998
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        Indicator semivariograms are indeed the perfect tools for
        detecting the presence of scale-dependent correlations
        between categories.
        A good reference for application of geostat structural tools
        to ecological data is:
        Rossi RE, Mulla DJ, Journel AG, Franz EH (1992) Geostatistical
        tools for modeling and interpreting ecological spatial dependence.
        Ecol. Monogr. 62: 277-314


        Regarding the general issue of scale-dependent correlations,
        you can take a look at the following references:
        - Goovaerts P, Webster R (1994) Scale-dependent correlation
        between topsoil copper and cobalt concentrations in Scotland.
        Eur. J. Soil Sci. 45: 79--95
        - Goovaerts P (1997) Geostatistics for natural resources evaluation.
        Oxford Univ. Press, New-York, 483 pp.



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        ________ ________
        | \ / | Pierre Goovaerts
        |_ \ / _| Assistant professor
        __|________\/________|__ Dept of Civil & Environmental Engineering
        | | The University of Michigan
        | M I C H I G A N | EWRE Building, Room 117
        |________________________| Ann Arbor, Michigan, 48109-2125, U.S.A
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        | |\ /| | E-mail: goovaert@...
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        On Wed, 15 Apr 1998, Yoshiro Nagao wrote:

        > My problem seems to be same with the captioned one:
        >
        > We collected several insect species(A,B,C,D...) at sampling locations.
        >
        > Species A and B are negatively correlated in number at each the location.
        >
        > However, when I make a interpolated picture by inverse distance weighting,
        > the density picture for A and B are nearly similar and are overlapped.
        > ( I made the programme.)
        >
        > I concluded that species A and B are in competition in micro habitat,
        > but their macro habitat are rather same.
        >
        > Actually A and B are near on their phylogenic tree.
        >
        > How can I geo-statistically show such a scale dependent
        > spatial correlation?
        >
        > "Variogram" is the suitable method?
        >
        > It would be appreciated if a good book on this matter is
        > recommended.
        >
        > "Steve Friedman" <friedman@...> sama said:
        > >I'm working with a very large regional analysis of presettlement vegetation
        > >patterns using General Land Office records. This data set is a point base
        > >system. Each point consists of from 1 - 4 entries for a tree species present
        > >at that location, absence data is not included in the data collection process.
        > >
        > >I'd like to model the presence of each species using indicator variograms for
        > >comparisons between the species and secondly to compare results from
        > >spatial autocorrelation for nominal data.
        > >
        > >My questions:
        > >1. Where can I find software applications for indicator variograms?
        > >
        > >2. What is the relationship between indicator variograms and nominal
        > > spatial autocorrelation? My assumption is that the techniques should
        > > produce similar results. Am I correct?
        >
        > Nagao Yoshiro
        > International Centre for Medical Research
        > Kobe University
        > --
        > *To post a message to the list, send it to ai-geostats@....
        > *As a general service to list users, please remember to post a summary
        > of any useful responses to your questions.
        > *To unsubscribe, send email to majordomo@... with no subject and
        > "unsubscribe ai-geostats" in the message body.
        > DO NOT SEND Subscribe/Unsubscribe requests to the list!
        >

        --
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