Quote:
Originally Posted by Moneyline
My understanding of expected utility theory is not 100%, but from my understanding expected utility can explain why individuals may choose to make -ev gambles, but it doesn't turn those -ev gambles into either +ev gambles or "good" choices.
Not quite. Basically, the concept of utility redefines what is "good."
You will never reach the long run when it comes to the lottery, so your actual results will never equal EV. Among a lottery-playing population, you'll have millions slightly below EV and one vastly above EV. The concept of utility means that it doesn't really make a difference whether you're $1 poorer than EV, but you're very happy being $1,299,999,999 above EV. The bet is utility+/EV-.
Now, if you go out and buy 10,000 lottery tickets, the situation is different. You're still very happy being $1,299,990,000 above EV, but you're now significantly unhappy about being $10,000 poorer than EV. The bet is utility-/EV-.
To be complete, imagine a reverse lottery. One player is selected from several hundred million, and his/her assets are seized and distributed among the others. To encourage people to participate, the government throws an extra $1,000,000 into the pool. So you have a 99.999999% chance of ending up a few cents richer, and a 0.000001% chance of having everything taken away from you. This would be a utility-/EV+ game that nobody would play.