When Fairness is Unfair: Understanding Norm Abandonment in Bargaining

Graduate School of Economics, Waseda University

with Linjia Jiang and Yoshio Kamijo

To examine how fairness norms shape agreements, we conduct an experiment, where participants first select a preferred allocation norm and subsequently decide whether to follow this rule in different resource division scenarios. Participants can choose from three principles: equal division, equal gain, and proportional division, which respectively represent strict egalitarian, liberal egalitarian and libertarian ideals. When paired with another sharing the same norm, participants decide whether to adhere to the projected division or negotiate a different outcome. Experimental results reveal that participants renege on the agreement more frequently when allocations are perceived as unfair to the self: high contributors in equal division and low contributors in proportional division. Furthermore, attachment to equality is significantly stronger than attachment to proportionality. Equal gain, representing a middle ground between two ideological extremes and coinciding with the Nash bargaining solution, is the most favored at both preselection and negotiation outcomes. We discuss several applications of our findings in the domain of peace negotiations.