Driving with mathematicians

Moebius Strippe — Sun, 12 Mar 2006 00:00:00 +0000

“How many gas stations do you think we’ll pass on the way home?”" “You mean on the side of the road, or at exits?”" “Whichever – places where we’d consider buying gas.”" “I don’t know, six, eight why?”" “Well, if we pass the first 1/e gas stations and then stop at the first place that offers cheaper gas, then we’ll maximize the chance that we’ll end up buying the cheapest gas. I mean, assuming that gas prices are random and don’t follow any trend with regards to location, which obviously isn’t the case.”" “Oh. Ha! But that’s not the algorithm we want – that one maximizes the probability of getting the cheapest gas; it doesn’t minimize the expected price of the gas we buy, which is what we want.”" “Oh, yeah, you’re right: if we apply that first algorithm, then in the likely event that we don’t get the very cheapest gas, there’s still a reasonable chance that we’ll end up with pretty expensive gas.”" “Right.” “So what’s the strategy for minimizing the expected price of gas?” “I don’t know.” “So, is there a probabilist in the house?

tall dark and mysterious » Queen of Sciences.

Driving with mathematicians