An article in the journal Neuron documents an experiment in which monkeys were trained to play Rock Scissors Paper.  When a monkey played a winning strategy he was likely to repeat it on the next round.  When he played a losing strategy he was likely to choose on the next round the strategy that would have won on this round.  The researchers were interested in how monkeys learn and they interpret the results as consistent with “regret”-based learning.

Unfortunately in the experiment the monkeys were playing against a (minimax-randomizing) computer and not other monkeys.  With this as a control it would now be interesting to see if they follow the same pattern when they play against another monkey.  (With this pattern, the winning monkey would be negatively serially correlated.)

Vueltiao volley: Victor Shao.