Rock Scissors Paper Game
An evolutionary game that actually turns out to be a children’s game is rock-paper-scissors. The game is simple – rock bests scissors (blunts it), scissors bests paper (cuts it), and paper bests rock (wraps it up). Anyone who has ever played this simple game knows that it is not sensible to have any favoured play – your opponent will soon notice this and switch to the winning counter-play. The best strategy (a Nash equilibrium) is to play a mixed random game with any of the three plays taken a third of the time. This, in EGT terms, is a mixed strategy. But many lifeforms are incapable of mixed behavior — they only exhibit one strategy (known as a “pure” strategy”). If the game is played only with the pure Rock, Scissor and Paper strategies the evolutionary game is dynamically unstable: Rock mutants can enter an all scissor population, but then – Paper mutants can take over an all Rock population, but then – Scissor mutants can take over an all Paper population – and on and on…. This is easily seen on the game payoff matrix, where if the paths of mutant invasion are noted, it can be seen that the mutant "invasion paths" form into a loop. This in triggers a cyclic invasion behaviour.
Read more about this topic: Evolutionary Game Theory
Famous quotes containing the words rock, paper and/or game:
“You have constantly urged the idea that you were persecuted because you did not come from West-Point, and you repeat it in these letters. This, my dear general, is I fear, the rock on which you have split.”
—Abraham Lincoln (18091865)
“A cow does not know how much milk it has until the milkman starts working on it. Then it looks round in surprise and sees the pail full to the brim. In the same way a writer has no idea how much he has to say till his pen draws it out of him. Thoughts will then appear on the paper that he is amazed to find that he possessed. How brilliant! he says to himself. I had no idea I was so intelligent. But the reader may not be so im pressed.”
—Gerald Branan (18941987)
“In the game of Whist for two, usually called Correspondence, the lady plays what card she likes: the gentleman simply follows suit. If she leads with Queen of Diamonds, however, he may, if he likes, offer the Ace of Hearts: and, if she plays Queen of Hearts, and he happens to have no Heart left, he usually plays Knave of Clubs.”
—Lewis Carroll [Charles Lutwidge Dodgson] (18321898)