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:
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—Thomas Szasz (b. 1920)
“It was because of me. Rumors reached Inman that I had made a deal with Bob Dole whereby Dole would fill a paper sack full of doggie poo, set it on fire, put it on Inmans porch, ring the doorbell, and then we would hide in the bushes and giggle when Inman came to stamp out the fire. I am not proud of this. But this is what we do in journalism.”
—Roger Simon, U.S. syndicated columnist. Quoted in Newsweek, p. 15 (January 31, 1990)
“Lyke as a huntsman after weary chace,
Seeing the game from him escapt away,
Sits downe to rest him in some shady place,”
—Edmund Spenser (1552?1599)