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Thread: Log transformed statistics

  1. 08-19-2008 01:39 PM #1
    kh11
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    Log transformed statistics



    Hello,
    I have a dataset that is log-normally distributed and I would like to know how to accurately calculate the CV and Standard Deviation. To get the mean (or rather the geometric mean) I first transform the data, calculate the mean, and then un-transform the data. It is my understanding, however, that the same can not be done for the CV and STD. Do you have any suggestions?
    Thank you
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  2. 08-19-2008 02:32 PM #2
    JohnM
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    I found this on Wikipedia:

    http://en.wikipedia.org/wiki/Geometr...dard_deviation
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  3. 08-19-2008 02:45 PM #3
    kh11
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    Thanks for the link. Any thoughts on the CV?
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  4. 08-19-2008 02:53 PM #4
    JohnM
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    Wild guess: geometric std dev divided by geometric mean?
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