Page 1 of 1

Problem 783

Posted: Sat Feb 05, 2022 1:08 pm
by spidersanghvi
So I do not know if asking this is fine but when I am calculating the value of E(2,2) I am getting the value 8.666667.Am I missing something?

Re: Problem 783

Posted: Sun Feb 06, 2022 6:30 am
by neverforget
Please include the link to the problem in the first post, like this: Problem 783 (View Problem)

And to answer your question, you must be missing something because $E(2,2)$ is easy enough to verify by hand, and the stated value in the problem is definitely correct. I would suggest carefully rereading the problem statement, as that is usually where the problem lies when small examples don't match.

Re: Problem 783

Posted: Thu Feb 24, 2022 6:13 pm
by PeterBurbery
I am wondering if the a sequence of balls is removed all at once or a ball is removed one by one.

Re: Problem 783

Posted: Thu Feb 24, 2022 7:21 pm
by RobertStanforth
PeterBurbery wrote: Thu Feb 24, 2022 6:13 pm I am wondering if the a sequence of balls is removed all at once or a ball is removed one by one.
"On each turn [...] $2k$ random balls are removed from the urn"
These $2k$ are selected in such a way that any possible choice of $2k$ is as likely as any other.
It doesn't make any difference to the distribution of $B_t$ whether all $2k$ balls for turn $t$ are selected/removed at once, or one at a time.

Re: Problem 783

Posted: Thu Feb 24, 2022 8:00 pm
by PeterBurbery
I am wondering if this is a place where I can ask questions about Wolfram mathematica and functions.

Re: Problem 783

Posted: Thu Feb 24, 2022 8:08 pm
by PeterBurbery
I'm just wondering but what does the expectation of mean?
Further define E(n,k) as the expectation of

Re: Problem 783

Posted: Thu Feb 24, 2022 9:11 pm
by jaap
PeterBurbery wrote: Thu Feb 24, 2022 8:08 pm I'm just wondering but what does the expectation of mean?
Further define E(n,k) as the expectation of
It means the expected value.