Descriptive Statistics

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Thanks so much for reading our publication. We hope you find it informative and useful. Happy charting and may the data always support your position.


Dr. Bill McNeese
BPI Consulting, LLC

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Comments (2)

  • DaleWJuly 3, 2017 Reply

    Bill, I've got bad news. Microsoft still has quirky quartiles. Neither their .INC or .EXC quartiles consistently follow the simple median inclusion and exclusion rule that you describe. The problem arises with even sample counts, which we might think would be simpler than odd.For instance, consider {1,2,3,4}. The 1st Quartile is obviously 1.5 and the 3rd Quartile is obviously 3.5 by either rule, right? Unfortunately Excel doesn't think so, because it uses interpolative quartiles and not truly inclusive or exclusive quartiles.

    • billNovember 21, 2018 Reply

      Yes, you are correct.  Excel does have quirky quartiles. The calculation of quartile has changed in Excel through difference versions.  It is not based on the medians that this publication originally implied.  I changed the article to reflect this.  Simply a case of taking one example, applying the media approach, and having it work – then assuming it was correct.  
      Thanks as usual.

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