Bargaining over a finite set of alternatives

We analyze bilateral bargaining over a finite set of alternatives. We look for “good” ordinal solutions to such problems and show that Unanimity Compromise and Rational Compromise are the only bargaining rules that satisfy a basic set of properties. We then extend our analysis to admit problems with countably infinite alternatives. We show that, on this class, no bargaining rule choosing finite subsets of alternatives can be neutral. When rephrased in the utility framework of Nash (1950), this implies that there is no ordinal bargaining rule that is finite-valued

Bargaining through Approval

The paper considers two-person bargaining under Approval Voting. It first proves the existence of pure strategy equilibria. Then it shows that this bargaining method ensures that both players obtain at least their average and median utility level in equilibrium. Finally it proves that, provided that the players are partially honest, the mechanism triggers sincerity and ensures that no alternative Pareto dominates the outcome of the game

Compromising on compromise rules

We propose three mechanisms to reach compromise between two opposing parties. They are based on the use of Rules of k Names, whereby one of the parties proposes a shortlist and the other chooses from it. Methods of this class are used in practice to appoint Supreme Court justices and have been recently proposed for arbitration selection processes. Those we suggest are flexible and allow the parties to participate in the endogenous determination of the role of proposer and the shortlist size. They involve few stages, implement the Unanimity Compromise Set, and are robust to the strategic inclusion of candidates

The attraction and compromise effects in bargaining: Experimental evidence

We experimentally investigate, in an unstructured bargaining environment with commonly known money payoffs, the attraction effect and compromise effect (AE and CE) in bargaining, namely, a tendency for bargainers to agree to an intermediate option (CE) or to an option that dominates another option (AE). We conjecture that the relevance of the AE and CE in bargaining is constrained by how focal the feasible agreements’ payoffs are. We indeed observe that there are significant AEs and CEs, but these effects are mediated by the efficiency and equality properties of the feasible agreements. Due to the allure of equality, the effects are harder to observe when an equal earnings contract is available. Decoys are more effective in shifting agreements from a very unequal contract to a less unequal one rather than the reverse

Random mechanism design on multidimensional domains

Ministry of Education, Singapore under its Academic Research Funding Tier