10 ROCK, PAPER …PAPER

In rock-paper-scissors, each player secretly positions a hand in the shape of either a rock, a piece of paper, or a pair of scissors. When a signal is given, players reveal their choices, and an intuitive rule is applied: paper covers rock, rock smashes scissors, scissors cut paper, and everything else is simply a tie. You have surely played this game from time to time and have probably thought of it as something like the flip of a fair coin or the roll of an unweighted die. That is, you have probably treated the game as if it is a completely fair, completely random way to make an unbiased choice. But is it really?