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Fit an equation

  1. Sep 18, 2004 #1
    Hi all,

    I have a scenario with three variables, X,Y,Z and Result This is what I know about them:

    X could go be from 1 – 100 say meters
    Y could be 0 – 31 say ranking
    Z could be 1- 100 say meters
    Result is in meters (1-100)

    For values of X between say 1-20 meters, and 80-100 meters it impacts the result very much i.e low values of Result i.e. like a bell shaped curve.
    If Y increases then the Result increases for the most part of course there could be some exceptions.
    IF Z increases then the Result increases again with an exception that if Z becomes like 50 meters then the probability of achieving that high Result (meters) is very low.

    How do I put together an equation that consists of X, Y, Z to achieve the Result. Should I assume a correlation coefficient and then try to fit an equation. I have no clue about this.
    Any help is greatly appreciated.

  2. jcsd
  3. Sep 18, 2004 #2


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    I'm not sure what you're trying to do but since this is a physics forum I imagine you're collecting data on some kind of physics experiment. You should probably have some kind of a model that relates "result" to the variables x, y and z. That model would have various parameters and you would, in essence, be trying to get a "best fit" to the data by adjusting those parameters.

    One way to accomplish that would be a least squares fit.
  4. Sep 19, 2004 #3


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    Given three variables, you can put them together to get whatever you want!

    WHAT is you function supposed to give?
  5. Sep 19, 2004 #4

    Dr Transport

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    as one great dead physicist has said, "give me one parameter, I can fit an elephant, two, I can make him grey and three, I can make his ears viggle"....Mani, you need to show us what you want to do and how you have worked on the problem so far. Then we can give guidance and help.
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