International cooperation over the major rivers in South Asia took a new turn with the signing in 1996 and 1997 of five innovative water, power and economic cooperation agreements. The innovations include four elements: (i) the transfer of some previously diplomatic questions into the sphere of...

We elicit human conditional punishment types by conducting experiments. We find that their punishment decisions to an individual are on average significantly positively proportional to other members’ punishment decisions to that individual.

We run an experiment with users of internet message boards. We find that forum users cooperate more with partners of their own forum than with partners from a different forum but they are equally altruistic when they made a gift to a partner of their forum or from another one. We also find that...

Costless pre-play communication has been found to effectively facilitate coordination and enhance efficiency in games with Pareto-ranked equilibria. We report an experiment in which two groups compete in a weakest-link contest by expending costly efforts. Allowing intra-group communication leads...

The ability of groups to implement efficiency-enhancing institutions is emerging as a central theme of research in economics. This paper explores voting on a scheme of intergroup competition which facilitates cooperation in a social dilemma situation. Experimental results show that the...

This Paper presents a formal theory of reciprocity. Reciprocity means that people reward kind actions and punish unkind ones. The theory takes into account that people evaluate the kindness of an action not only by its consequences but also by the intention underlying this action. The theory...