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One robust result in experimental economics is the failure to observe equilibrium play in the ultimatum game. A heretofore unnoticed feature of the game is that neither player voluntarily chooses to play the game. Motivated by Adam Smith’s proposition that beneficence—like that of non‐ equilibrium play in the ultimatum game—cannot be extorted by force, we offer the responder the opportunity to opt out of the game for a mere $1 payoff for both players. We observe high rates of equilibrium play with highly unequal splits when responders choose to play such ultimatum games with both fixed and variable sums.


Working Paper 17-17

This working paper was later published as:

Smith, V., & Wilson, B. (2018). Equilibrium play in voluntary ultimatum games: Beneficence cannot be extorted. Games and Economic Behavior, 109, 452-464. doi: 10.1016/j.geb.2018.01.006



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