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  1. #1
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    simple question: descriptives in excel




    Hi, I was just looking at descriptives in excel and I saw that I get different values when I do it manually, and I'm not sure why. If I have the following column (A1:A8) in excel:
    [1
    2
    3
    4
    3
    5
    2
    3]

    The mean = 2.875. for each column I subtract the datapoint from the mean and get the following column of errors:

    [1.875
    0.875
    -0.125
    -1.125
    -0.125
    -2.125
    0.875
    -0.125]

    Fine. I square these and then get the sum of squares:

    [3.515625
    0.765625
    0.015625
    1.265625
    0.015625
    4.515625
    0.765625
    0.015625
    ]

    SS = 10.875. I then take SS/n-1 to get variance=0.359375. I understand that this is the sample variance. If I then take the function =VAR.S(A1:A8), the value returned is 1.553571429. This ultimately leads my standard deviation to turn out different to the excel formula as well. Why is this happening? Am I making a silly mistake?

    Thanks

  2. #2
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    Re: simple question: descriptives in excel

    The is a difference between (SS/n) - 1 and SS/(n-1)
    I don't have emotions and sometimes that makes me very sad.

  3. #3
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    Re: simple question: descriptives in excel


    Doh.... that's embarrassing

    Thanks

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