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  1. Commons Math
  2. MATH-1373

In LogNormalDistribution.java, it appears shape & scale are reversed/mis-labelled.

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Details

    • Bug
    • Status: Resolved
    • Minor
    • Resolution: Won't Fix
    • 3.6.1
    • 4.0
    • None
    • None

    Description

      When I compute the logshape and log scale based on the formulas on wikipedia's lognormal distribution page that use empirical mean and variance, I found that the getNumericalMean() method was not returning the empirical mean.

      However, upon just trying to reverse the shape and scale parameters in the constructor proved to fix the problem, and the object then returns the correct empirical mean.

      Attachments

        1. MATH-1373.patch
          5 kB
          Karl D. Gierach

        Issue Links

          is related to

          Bug - A problem which impairs or prevents the functions of the product. RNG-96 AhrensDieterMarsagliaTsangGammaSampler incorrectly names parameters

          • Minor - Minor loss of function, or other problem where easy workaround is present.
          • Closed

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              Unassigned Unassigned
              kgierach Karl D. Gierach
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