Chimps beat humans at game theory

In Chimpanzee choice rates in competitive games match equilibrium game theory predictions, a paper in Nature by Colin Camerer and colleagues, researchers document the astounding performance of chimpanzees in classic game-theory experiments -- a performance that's substantially superior to humans who play the same games:

Camerer had chimps play versions of the matching pennies game also called the cat and mouse game. In the cat and mouse game each player can go left or go right. The cat wins when cat and mouse choose the same strategy. The mouse wins when they choose different strategies. In the simple version the best strategy is 50:50, toss a coin. When the payoffs change, however, the optimal strategies still involve randomization but they change in surprising and nonobvious ways.

Chimps play the cat and mouse game very well. First, the chimps converge on the Nash Equilibrium strategies. In one set of games the Nash equilibrium strategies had randomization frequencies of .5, .75 and .8 and the chimps played .5, .73 and .79. Second, when payoffs change the chimps adapt their strategies very quickly simply by observation of outcomes.

Chimps Rock at Game Theory [Alex Tabarrok/Marginal Revolution]

(via Kottke)

Notable Replies

  1. Some call it primatology. I call it Viral Movie Marketing.

  2. Once again, a completely hyperbolic and meaningless headline by doctorow.

  3. Fang says:

    In fact, look at the supplementary material. The thing to note is that this is not a zero sum game. By deviating from the nash equilibrium, the human participants actually achieve a higher monetary payout from the experimenters than the 'optimal' choice would give them, far superior to what the chimps manage.

    Chimps are not smarter than humans. The humans in the experiment were smarter than the researchers.

  4. And if you look at chimp society and you look at human society, this is exactly what you should expect.

    As I say every time game theory comes up, empirical studies tend to show this pattern when they actually run game theory tests with human subjects. The only test subjects who do what the simple models predict are Economics students.

    Human society has acquired formidable defences against "always defect" style behaviour, and this is only broken down by rigorous training in selfish oversimplification. Unfortunately, we are living in the midst of a political project to do just that.

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