Many of you have heard of the Ultimatum Game:
The ultimatum game is an experimental economics game in which two parties interact anonymously and only once, so reciprocation is not an issue. The first player proposes how to divide a sum of money with the second party. If the second player rejects this division, neither gets anything. If the second accepts, the first gets his demand and the second gets the rest.
In theory a "rational" player should accept whatever is offered when there isn't a repeated iteration. Reality is different. From The Economist:
...Those results recorded, Dr Burnham took saliva samples from all the students and compared the testosterone levels assessed from those samples with decisions made in the one-round game. As he describes in the Proceedings of the Royal Society, the responders who rejected a low final offer had an average testosterone level more than 50% higher than ...
