Marilyn and the Goats: Probability Paradoxes

A lecture on the “Monty Hall Problem”, one of the most striking puzzles for probability. Professor Stewart here gives the problem as something like the following:

You have a choice of three doors: Behind one of them is Andromeda, but behind the other two is a Gorgon. Perseus suggests the tactic of choosing the one door and then sticking with it, even after another door is opened and he is given the chance to swap. In contrast, Pigasus suggests the tactic of always switching the chosen door once one of the two alternative doors are opened. Who has the better option?