It's useful if you don't know what $threshold is or if you want to get more "bang for your buck". I believe there's a chapter in Freakonomics that deals with t

It's useful if you don't know what $threshold is or if you want to get more "bang for your buck". I believe there's a chapter in Freakonomics that deals with this problem and, if I'm not mistaken, talks about a situation where you might want to figure out some of the best places to eat in town without needing to visit all the places in town.