Who stole my EV?
I wanted to reframe Shannon's Demon which I came across lately from a betting perspective and see what it tells us about Expected Value and staking. The idea is that I have a bank, say €100. I have a bet that I can make every day, suppose I am quite a professional and I am easily capable of finding sportsbooks offering 2/1 (3.0, +200) on a true even money chance (2.0, +100). That is a pretty huge edge right there. There is no way that I can screw this one up! (Is there?). I am going to bet half my bank each time. Its a big edge, I dont want to waste it. Also as I half my bank it will prevent me from going bust, it may reduce during a long drawdown but cannot reach zero (in theory!) and is unlikely to go below say €1 - which would double up fast again in good times. And as likely it is to drop below €1, it is equally likely to double up to €10,000s which more than balances out that risk. So you take your €100 balance and bet half ie €50 @ 2/1 with a ...