Re: Weekend Puzzle
- From: Jerry Avins <jya@xxxxxxxx>
- Date: Tue, 30 May 2006 13:12:47 -0400
Ikaro wrote:
I think we can solve this by treating n is a random variable.
In this case n is a negative binomial random variable, with 1 sucess in
n trials.
The mean of the negative binomial in this case is 2.
So that:
What is the expected value of winnings assuming many games are
played? 2
What entry fee would make it a fair game? 2*(2^(2-1))=4
What would you pay?
1 (I am cheap)
The expected return on any bet is the sum of (the return for outcome n
times the probability of outcome n) over all n. It is therefore infinite
in the case of unlimited payout. If the payout is limited, the expected
value of a game is finite. Even for large limits, the expected value is
surprisingly small. http://en.wikipedia.org/wiki/St._Petersburg_paradox
has this table:
Backer Bankroll Expected value of lottery
Friendly game $64 $3.50
Millionaire $1,050,000 $10.50
Billionaire $1,075,000,000 $15.50
Bill Gates $51,000,000,000 (2005) $18.00
U.S. GDP $11.7 trillion (2004) $22.00
World GDP $40.9 trillion (2004) $23.00
Googolnaire $10^100 $166.50
Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
.
- Follow-Ups:
- Re: Weekend Puzzle
- From: Ikaro
- Re: Weekend Puzzle
- From: Ikaro
- Re: Weekend Puzzle
- From: Ikaro
- Re: Weekend Puzzle
- References:
- Weekend Puzzle
- From: Jerry Avins
- Re: Weekend Puzzle
- From: Sukrut
- Re: Weekend Puzzle
- From: Jerry Avins
- Re: Weekend Puzzle
- From: Ikaro
- Weekend Puzzle
- Prev by Date: [FURTHER OT ;] - Why doesn't "SOMEONE"? was [Re: OT: Contact with Julius Kusuma]
- Next by Date: Re: Type fixed piont
- Previous by thread: Re: Weekend Puzzle
- Next by thread: Re: Weekend Puzzle
- Index(es):
Relevant Pages
|