a tip is allowed from responder back to proposer, a feature of the trust game, and net splits tend to be more equitable. The "reverse ultimatum game" gives more power to the responder by giving the proposer the right to offer as many divisions of the endowment as they like. Now the game only ends when the responder accepts an offer or abandons the game, and therefore the proposer tends to receive slightly less than half of the initial endowment. Incomplete information ultimatum games: Some authors have studied variants of the ultimatum game in which either the proposer or the responder has private information about the size of the pie to be divided. These experiments connect the ultimatum game to principal-agent problems studied in contract theory. The pirate game illustrates a variant with more than two participants with voting power, as illustrated in Ian Stewart's "A Puzzle for Pirates". See also Dictator game Fair division experiments Gift-exchange game Impunity game Neuroeconomics Public goods game Prisoner's dilemma Social preferences References Further reading Bicchieri, Cristina and Jiji Zhang (2008). "An Embarrassment of Riches: Modeling Social Preferences in Ultimatum games", in U. Maki (ed) Handbook of the Philosophy of Economics, Elsevier External links Video lecture on the ultimatum game Non-cooperative games Moral psychology Social science experiments