Distribution of Variation

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Distribution of Variation
Message posted by esan (via 63.206.246.74) on September 19, 2001 at 2:51 PM (ET)

What distribution is used for Variation? Specifically, I have a confidence interval of 0.95 for the variation of a sample size of 20. What I want to obtain is the maximum variation, in other words, what is the upper limit of the confidence interval for the variance? I am using the chi-squared distribution but am not getting the correct results. Anybody out there who has any idea on how to get this please respond to my question, it will be very helpful.

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Re: Distribution of Variation
Message posted by Jack Tomsky (via 208.249.113.130) on September 19, 2001 at 7:43 PM (ET)

To get an upper 95% confidence limit for the variance, multiply the sample variance (from your data of twenty points) by 19 and then divide by the lower 5 percentile of the chisquare distribution with 19 degrees of freedom.

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