"Voice Matters in a Dictator Game"(in Japanese)

We examine a dictator game with a "voice" option in the laboratory. In the dictator game, player 1 dictates how to divide a pie, and player 2 simply receives his/her share, i.e., unlike in an ultimatum game, he/she does not have an option to reject this division. In our experiment, player 2 has an opportunity to state a payoff-irrelevant request for the minimum acceptable offer before player 1 dictates his/her offer. In this game,it is predicted not only by the standard game theory, but by the behavioral game theory such as the theory of other-regarding preferences, that player 1's offer is independent of player 2's request. Some findings based on our data are as follows: the above independence hypothesis is rejected; as player 2's request increases, player 1's offer increases when the requests are less than 50% of the pie; on the other hand, when the request goes beyond 50% of the pie, the offer decreases as the request increases. That is, "voice" matters without having strategic meaning. We also conduct a clustering analysis to find three notably different tendencies among player 1's behavior.