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Homework Help: R square

  1. May 1, 2006 #1
    Hi there,

    I have googled for the R square formula, but it's very confusing, so I need some help. Please come up with an example on how to use it, if I have a exponential function on how i want to calculate its R square.

    Thanks:cry:
     
  2. jcsd
  3. May 1, 2006 #2

    Integral

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    [itex]R^2[/itex] is used to gauge the "goodness" of "fit" of a data set to some known function. So you need a data set and a function, you cannot meaningfully speak of [tex]R^2[/itex] of a function by itself.
     
  4. May 2, 2006 #3
    If I then have a table of data:

    0 2
    40 6
    80 8
    120 12
    160 18
    200 24
    240 42
    280 82
    320 110
    360 190
    400 300
    440 500
    480 800

    ... and I want to find the R^2, what should I do (I don't want to use software)?
    :surprised
     
  5. May 2, 2006 #4

    J77

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    Last edited: May 2, 2006
  6. Mar 25, 2010 #5
    google: "Pearson product moment correlation coefficient"

    multiply PPMCC by itself for R^2

    http://mathbits.com/Mathbits/TISection/Statistics2/correlation.htm [Broken]

    sorry it's 4 years late...
     
    Last edited by a moderator: May 4, 2017
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