so I"m trying to understand pdf, the one where the formula is ((rCk) * (wCn-k))/(NCn). Here, xCx means x chooses x.(adsbygoogle = window.adsbygoogle || []).push({});

anyways, N is the total, and n is how much you sample out of it. and we know that r + w = N.

what is k?

I know this is diffenrent for all problems, but is there an analogy..I"m having trouble setting things up.

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# Having trouble w/ understanding pdf

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