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Stats Questions: Q5

iii) You will not be able to separate the players if $$r>n-r+1,$$ $$2r>n+1,$$ $$r>\frac{1}{2} (n+1)$$ ? On the solutions it has $r>\frac{1}{2}(n-1)$ as the case instead so I was a bit confused, is this an error in the solutions or have I missed something?
Thanks a lot

You're correct. The non-zero probability case is only valid for $r \leqslant \frac{1}{2}(n+1)$. I'm sure the mistake will be corrected soon, thanks for pointing it out.

[Incidentally, the blue text in part (ii) is also "wrong". You can write it in a nicer (subjective) way as $\displaystyle (n-r+1) {{n}\choose {n-r}}^{-1}$, which you might like to think about the alternative argument it suggests.

Will sort it today. Thanks for pointing it out!

Solutions have been updated, and I have tweaked the "blue comment" as well. Thanks both!

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