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a little challenge (math)

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ARandomPerson
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21 Feb 2009, 7:13 am

with the birthday problem, at what amount of people will there be a 50/50 chance of success or not.
Note you would need a regression to come up with the exact (or closest answer)



lau
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21 Feb 2009, 8:13 am

If the question is "Given a room full of people, randomly gathered together, how many people do there have to be, for it to be odds-on that at least one pair of them have the same day of the year as their birthday." then the answer is 23.


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twoshots
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21 Feb 2009, 10:56 pm

ARandomPerson wrote:
Note you would need a regression to come up with the exact (or closest answer)

I conclude, thus, that you are allowing for fractions of people. I really have always thought the birthday problem should be more macabre.


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Death_of_Pathos
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23 Feb 2009, 4:30 am

twoshots wrote:
ARandomPerson wrote:
Note you would need a regression to come up with the exact (or closest answer)

I conclude, thus, that you are allowing for fractions of people. I really have always thought the birthday problem should be more macabre.


That fraction of a person only has a single birthday - its the same as allowing the extra person whole.



twoshots
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23 Feb 2009, 6:58 am

Death_of_Pathos wrote:
twoshots wrote:
ARandomPerson wrote:
Note you would need a regression to come up with the exact (or closest answer)

I conclude, thus, that you are allowing for fractions of people. I really have always thought the birthday problem should be more macabre.


That fraction of a person only has a single birthday - its the same as allowing the extra person whole.

I anticipated as much, but I think we should define it to be otherwise so as to make reality better.


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