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:
“Safe upon the solid rock the ugly houses stand:
Come and see my shining palaces built upon the sand.”
—Edna St. Vincent Millay (1892–1950)
“Evolution is the law of policies: Darwin said it, Socrates endorsed it, Cuvier proved it and established it for all time in his paper on “The Survival of the Fittest.” These are illustrious names, this is a mighty doctrine: nothing can ever remove it from its firm base, nothing dissolve it, but evolution.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
“My first big mistake was made when, in a moment of weakness, I consented to learn the game; for a man who can frankly say “I do not play bridge” is allowed to go over in the corner and run the pianola by himself, while the poor neophyte, no matter how much he may protest that he isn’t “at all a good player, in fact I’m perfectly rotten,” is never believed, but dragged into a game where it is discovered, too late, that he spoke the truth.”
—Robert Benchley (1889–1945)