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Thread: Confidence interval for the standard deviation

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    Confidence interval for the standard deviation




    Hi,
    I'm using the typical formula SQRT(((N-1)*s^2)/(CHISQ.INV((1-Confidence)/2, N-1))).
    By mistake I entered a very low confidence and I noticed that it did not include the calculated standard deviation.
    Can someone explain me the reason?
    I've double checked the results with Minitab and they are correct.

    Thansk

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    Re: Confidence interval for the standard deviation


    Your formula only computes one side of the confidence interval. What do you get for the other end point? And telling us what numbers you're using and what you end up getting would be useful as well.
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