Simultaneous but independent ultimatum game: strategic elasticity or social motive dependency?

• Published in: International journal of game theory 2019-03, Vol.48 (1), p.61-80
• Main Authors: Otto, Philipp E., Dittmer, Daniel
• Format: Article
• Language: English
• Subjects: Altruism; Behavioral/Experimental Economics; Dependence; Dependency; Economic Theory/Quantitative Economics/Mathematical Methods; Economics; Economics and Finance; Elasticity; Game Theory; Games; Income distribution; Inequality; Operations Research/Decision Theory; Original Paper; Social and Behav. Sciences; Social sciences
• ISSN: 0020-7276; 1432-1270
• DOI: 10.1007/s00182-018-0646-6

Ultimata bargaining experimentally investigates the responder behavior for multiple proposers, that is, the responder’s decision to accept or reject an offer conditional on another parallel offer. Responders’ strategies combine the two formally independent but parallel games as if inducing competition among proposers by more frequently rejecting an offer when it is the lower one of the two offers received simultaneously. Furthermore, proposers’ public offers strongly correlate, due to adapting over repetitions to the parallel offer or because of only slightly outbidding the other proposer’s offer if known before their own announcement. Social preferences of inequity aversion or of pure altruism for income distributions resulting from simultaneous ultimata cannot explain a positive dependency of own offers on other parallel offers, and joint responsibility is proposed as a reference-dependent social motive.