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

[ai-geostats] Comparison of two point datasets

Expand Messages
  • Fábián József
    Dear listers, My question is about comparing two value lists mapped onto the same point pattern: We have calculated a kind of economical potential estimate
    Message 1 of 2 , Nov 22, 2004
    • 0 Attachment
      Dear listers,

      My question is about comparing two value lists mapped onto the same
      point pattern:
      We have calculated a kind of economical potential estimate from data
      collected for 576 towns from gravitation modell using linear distances
      between towns first, then using the minimum time required to reach one
      town from the other via road network. So, we have two values for the
      same 576 points which differ from each other with some magnitude and in
      spatial distribution, too. We would like to spatially compare two data
      to find areas where the two methods gives the most different results.

      Our idea was to calculate a (simple) linear regression for the two
      values, and then map the residual values, looking for the continuous sub
      areas where residuals are autocorrelated. We are not interested in
      estimation, but in finding the anomaleous places, where one modell
      locally significally over- or underestimates the other one.

      I am interested in your opinion about this approach, I would be thankful
      to get ideas about probably better (standard?) methods for comparing two
      mapped value sets.

      Jozsef Fabian
    • Wolfram Ruehaak
      Dear all, I have difficulties to find information s about the following problem. I have a lot of spatially scattered measurements. These measurements have -
      Message 2 of 2 , Nov 29, 2004
      • 0 Attachment
        Dear all,

        I have difficulties to find information's about the following problem.

        I have a lot of spatially scattered measurements. These measurements
        have - resulting from different measurement methods - different
        measurement errors, which are known.

        For example some have an total error of 5%, some of 10% and a third
        group of 20%.

        I want to give these values a quality-weight in the range from 0.0 to
        1.0. (In this case three different weights.)

        How can I do this?

        Simple is a weight = 0 which is a value so bad I don't want to use it,
        and a weight = 1 which could be the value for the group with the best
        measurements (in this case error = 5%).

        Is there a statistically firmed way to quantify the weights.

        Any suggestions will be very welcome.
        Is there any literature that discusses this matter?

        Thanks in advance.

        Wolfram Ruehaak
      Your message has been successfully submitted and would be delivered to recipients shortly.