The news release mentions that they played a prisoner's dilemma game and that all of the subjects were women. It did not say exactly what the payoffs were but they were awarded money.
The article also said: "Mutual cooperation was the most common outcome in games played with presumed human partners in both experiments, even though a player was maximally rewarded for defecting when the other player cooperated." When I play the prisoner's dilemma in class, I see very little cooperation. I do it with coins, face to face. If they both play heads, they get 3 each. 1 if they both play tails. If person A plays head while person B plays tails, A gets 0 and B gets 5. There are repeated trials and the students simultaneously open their hands to see the other's coin. After each trial they have to at least pretend that they might be changing their choice. Close hands, open again. It is only played for extra credit, not money. But I still see very little cooperation (heads). Over the years, I have not noticed that women are especially more cooperative than men. So it is very surprising to see the above quote. Maybe I am running the game wrong somehow and that is why I get little cooperation. If anyone has any suggestions, please email me. Cyril Morong
