On 6/26/07, John Randall <[EMAIL PROTECTED]> wrote:
Raul Miller wrote:
> I am rather dubious of any context where that's a significant
> issue.
Actually, you have to rely on this: the sample variance with (n-1) in
the denominator is an unbiased estimator of the population variance:
with denominator n, it is not.
I believe I understand the reasoning -- that if you know that you
are computing standard deviation and you have n-1 deviations that
you know also know the nth (subtract the sum of the rest from
zero).
Or, put more qualitatively, it can be said to be a slight exaggeration
of the deviation to account for the fact that our mean is probably
slightly off.
My issue is that in any context where this is significant, you've
got bigger problems.
--
Raul
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