A martingale (her double-or-nothing coin flip) is only infinite estimated return if you have infinite dollars to spend on it. Otherwise the expectation is bankruptcy. The reason people don't do it is not because they have a concave utility function, it's because it doesn't work. How do you go to MIT and not know this wtf.
A martingale (her double-or-nothing coin flip) is only infinite estimated return if you have infinite dollars to spend on it. Otherwise the expectation is bankruptcy. The reason people don't do it is not because they have a concave utility function, it's because it doesn't work. How do you go to MIT and not know this wtf.