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Topic: Expectation of the variance
Replies: 1   Last Post: Mar 23, 2011 11:34 PM

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Steven D'Aprano

Posts: 21
Registered: 3/22/11
Re: Expectation of the variance
Posted: Mar 23, 2011 11:34 PM
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On Wed, 23 Mar 2011 15:28:51 -0700, Ray Vickson wrote:

> I think that the OP's problem stems from trying to use the formulas
> where they do not apply. He does not have an iid sample, because the
> only combinations he looks at are those in which there are no
> repetitions; that is, he is sampling *without replacement* (he does not
> allow things like (1,1,1); he only allows things like (1,2,3).) That
> makes his successive sample values dependent instead of independent, so
> the formulas he cites (which assume _independence_) do not apply.

Ahaha! That's what I'm missing, thanks.

Works fine once I swap to sampling with replacement instead.


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