Imagine that you’re on a game show, and you’re given the choice of a mystery prize behind one of three doors: Behind one door is a car; behind the other two doors are goats. You pick a door, say No. 1 and the host, who knows what’s behind the doors, opens another door, say No. 3, which has a goat. He then says to you, “Do you want to stick with door No. 1 or switch to door No. 2?” What do you do? Would you stick with your original pick or switch? Would either choice give you a better chance to winning the car?