Evolution in Imperfect Commitment Bargaining– Strategic versus Ignorant Types

To commit credibly in bargaining is crucial: In the ultimatum game with its one–sided early commitment power the “proposer” gets (nearly) the whole pie while the“responder” is left with (almost) nothing. When both parties commit simultaneouslythe (a)symmetric Nash(1950)–bargaining solution, however, predicts (moreor less) equal shares. Relying on a continuous connection of these two games bya one parameter–family of games (Fischer et al. 2003), we distinguish two behavioraldispositions, namely (1) neglecting early commitment and (2) reacting to itstrategically. Based on their payoff implications we derive the evolutionarily stablebehavioural disposition. This sheds new light on the hypothesis that in experimentsparticipants neglect subtle strategic aspects like the sequence of moves.