The other day I was musing about a reasonable approach to playing games like the big lotteries. They don't cost a lot and losing $40 is not a life changing event for me, but clearly winning a few hundred million dollars is life changing.
My first thought turned to, well if you just play when the expected value is greater than the cost of the ticket that is "rational". But when I started thinking about it, and even doing some calculations for when that EV condition exists (for things like Mega Millions the jackpot has to be greater then about 550 million) it struck me that the naive EV calculation must be missing something. The odds of actually winning the jackpot are really, really low (as opposed to just really low to rather low for the other prizes). And the payoffs that go into the EV calculation are hugely skewed by the top prices.
I suspect this must be a situation that generalized to other settings and am wondering if anyone knows of better approaches than merely the naive EV calculation. And to be sure I'm using the term as everyone expects, EV just equals the probability weighted payoffs minus the cost of the ticket.
Yes, I think performance ultimately matters much more than risk preferences. If you really want to take that into account you can just define utility as a function of wealth, and then maximize the growth of utility instead. But I think risk-aversion has been way overemphasized by academics that weren't thinking about ergodicity, and were thinking along St Petersburg Paradox lines that any +EV bet must be rational, so when people don't take +EV bets they must be irrationally risk-averse.