Bargaining under Uncertainty and the Monotone Path Solutions

Uncertainty with respect to the feasible set of utility vectors is introduced in an axiomatic bargaining model. Given a criterion for nonprobabilistic decision-making under uncertainty, a natural efficiency requirement can be imposed on a bargaining solution. Using the maximin ordering, thestrictly monotone pathsolutions (generalizations of theegalitariansolution) to the bargaining problem are characterized as the only continuous solutions that satisfy this efficiency axiom. If the maximin criterion is replaced by the maximax ranking or a strict convex combination of the maximin and the maximax criterion, imposing our efficiency axiom and continuity leads to thedictatorialsolutions.Journal of Economic LiteratureClassification Number: C78.     

Multilateral Bargaining Problems

In many situations in economics and political science there are gains from forming coalitions but conflict over which coalition to form and how to distribute the gains. This paper presents an approach to suchmultilateral bargaining problems. Asolutionto a multilateral bargaining problem specifies an agreement for each coalition that is consistent with the bargaining process in every coalition. We establish the existence of such solutions, show that they are determined by reservation prices, and characterize these reservation prices as the payoffs ofsubgame perfect equilibrium outcomesof a non-cooperative bargaining model.Journal of Economic LiteratureClassification Numbers: C71, C72, C78.     

Trade Negotiations under Alternative Bargaining Structure

We build a bargaining model, in which a country (leader) decides whether or not to form a free trade agreement with other nations (followers), either through a sequential or a multilateral bargaining procedure. Unlike Aghion et al. ( 2007 , Journal of International Economics, 73, 1–30), in our specification of multilateral bargaining, the leader can collude with all those follower countries who agree to its offer. This has important implications for the choice of sequential and multilateral bargaining by the leader in presence of coalition externalities. Moreover, this bargaining procedure ensures that “stumbling block” equilibrium will never occur.     

The Choquet Bargaining Solutions

We axiomatically investigate the problem of rationalizing bargaining solutions by social welfare functions that are linear in every rank-ordered subset of Rⁿ₊ . Such functions, the so-called Choquet integrals, have been widely used in the theories of collective and individual choice. We refer to bargaining solutions that can be rationalized by Choquet integrals as Choquet bargaining solutions. Our main result is a complete characterization of Choquet bargaining solutions. As a corollary of our main result, we also obtain a characterization of the generalized Gini bargaining solutions introduced by Blackorby et al. (1994, Econometrica62, 1161–1178). Journal of Economic Literature Classification Numbers: D71, C78.     

Bargaining in Uncertain Environments: A Systematic Distortion of Perfect Equilibrium Demands

We present data supporting the notion that subjects distort monotonically subgame perfect equilibrium demands in two-person discount bargaining games, where, in addition to the traditional offer counter-offer sequence of moves, a player who rejects an offer may either be forced out of the bargaining or be given the option to opt out. Subjects also exhibit behavioral adaptivity—learning from past demands in a search for the highest acceptable demand. These reuslts are consistent with previous experimental evidence for these types of games, but stand in sharp contrast to those obtained in discount bargaining where side options are not available.Journal of Economic LiteratureClassification Numbers: C72, C78.     

Matching markets with price bargaining

The extant microeconomic literature on matching markets assumes ordinal preferences for matches, while bargaining within matches is mostly excluded. Central for this paper, however, is bargaining over joint profits from potential matches. We investigate, both theoretically and experimentally, a seemingly simple allocation task in a 2×2 market with repeated negotiations. When inefficiency is possible, about 1/3 of the complete matches are inefficient and, overall, more than 3/4 of the experimental allocations are unstable. These results strongly contradict existing bargaining theories requiring efficient matches. Even with regard to efficient matches, the tested theories perform poorly. Standard bargaining and behavioral concepts, such as Selten’s (1972) Equal Division Core, are outperformed by the simplistic ε-Equal Split, i.e., an equal split of the joint profit plus/minus ε.     

Subbalanced games and bargaining sets

Summary. In defining a bargaining set, it is desirable to require that a counterobjecting coalition has a non-empty intersection with the objecting coalition. We refer to this as the intersection property and define a bargaining set, MB ₁, that imposes this property on a variant of the bargaining set defined by Vohra (1991). To study the existence of MB ₁, a new version of the KKM theorem is proposed and the concept of a subbalanced game is introduced. We also provide conditions for the non-emptiness of MB ₂, a bargaining set introduced by Zhou (1994) which imposes the additional restriction that the objecting coalition not be a subset of the counterobjecting coalition.Received: 9 December 2002, Revised: 6 December 2004, JEL Classification Numbers: C71. Correspondence to: Chih ChangThe authors are very grateful to a referee who proposes many helpful comments on both substantive matters and exposition which much improve the paper.     

A note on bargaining over a finite number of feasible agreements

Summary In this note we show that theuniqueness of the subgame perfect equilibrium of Rubinstein's (1982) bargaining theory does not hold if the number of feasible agreements isfinite. It will be shown thatany Pareto-efficient agreement (belonging to thefinite set of feasible agreements) can be supported as a subgame perfect equilibrium of the Rubinstein alternating-offers bargaining game, provided the length of a single bargaining period is sufficiently small.     

Nonconvex n-person bargaining: efficient maxmin solutions

Summary. This paper provides an axiomatic characterization of a family of so-called efficient maxmin solutions which can be seen as generalizations of the Kalai-Smorodinsky solution to nonconvex n-person bargaining problems. Moreover, it is shown that even though there are several efficient maxmin solutions for some bargaining problems, there is typically a unique efficient maxmin solution. Received: February 15, 2001; revised version: November 14, 2001     

Finite Horizon Bargaining and the Consistent Field

We explore the relationships between noncooperative bargaining games and the consistent value for nontransferable utility (NTU) cooperative games. A dynamic approach to the consistent value is introduced: the consistent vector field. The main contribution is to establish that theconsistent fieldis intimately related to the concept ofsubgame perfectionfor finite horizon noncooperative bargaining games, as the horizon goes to infinity and the cost of delay goes to zero. We then show that in the general NTU case—unlike the transferable utility and pure bargaining cases—the finite horizon subgame perfect equilibria need not approach the consistent value.Journal of Economic LiteratureClassification Numbers: C71, C72.     

A Note on Multi-Issue Two-Sided Bargaining: Bilateral Procedures

This note considers a two-sided multi-issue bargaining problem in which players that belong to the same “side” may have conflicting priorities regarding the different negotiated issues. The note examines different bilateral bargaining procedures and shows the different equilibrium settlements that they yield. In particular the note examines the possibility that group heterogeneity (conflicting priorities) may be exploited in order to gain a better settlement. The different potential outcomes that are implied by the different procedures explain why we often observe such intense negotiation over bargaining procedures. Moreover, the conflict over procedure can be substantial, among parties with common interest as well as between opposing players. Journal of Economic Literature Classification Number: C7.     

Private takings

This paper examines the implications associated with a recent Supreme Court ruling, Kelo v. City of New London (2005). Kelo can be interpreted as supporting eminent domain as a means of transferring property rights from one set of private agents—landowners—to another private agent—a developer. Under voluntary exchange, where the developer sequentially acquires property rights from landowners via bargaining, a holdout problem arises. Eminent domain gives all of the bargaining power to the developer and, as a result, eliminates the holdout problem. This is the benefit of Kelo. However, landowners lose all their bargaining power and, as a result, their property investments become more inefficient. This is the cost of Kelo. A policy of eminent domain increases social welfare compared to voluntary sequential exchange only when the holdout problem is severe, and this occurs only if the developer has very little bargaining power. We propose an alternative government policy that eliminates the holdout problem but does not affect the bargaining power of the various parties. This alternative policy strictly dominates a policy of eminent domain, which implies that eminent domain is an inefficient way to transfer property rights between private agents.     

N-PERSON NASH BNARGAINING WITH VARIABEL THREATS*

We consider two models of n-person bargaining problems with the endogenous determination of disagreement points. In the first model, which is a direct extension of Nash's variable threat bargaining model, the disagreement point is determined as an equilibrium threat point. In the second model, the disagreement point is given as a Nash equilibrium of the underlying noncooperative game. These models are formulated as extensive games, and axiomatizations of solutions are given for both models. It is argued that for games with more than two players, the first bargaining model does not preserve some important properties valid for two-person games, e.g., the uniqueness of equilibrium payoff vector. We also show that when the number of players is large, any equilibrium threat point becomes approximately a Nash equilibrium in the underlying noncooperative game, and vice versa. This result suggests that the difference between the two models becomes less significant when the number of players is large.     

The separability principle in bargaining

Summary. We investigate the implications of the separability principle in the context of bargaining. For two bargaining problems with the same population, suppose that there is a subgroup of agents who receive the same payoffs in both bargaining problems. Moreover, if we imagine the departure of this subgroup with their payoffs, then the remaining agents face the same opportunities in both bargaining problems. The separability principle requires that under these hypotheses, the remaining agents should receive the same payoffs in both bargaining problems. We begin with investigating the logical relations between separability and two other axioms, contraction independence and consistency. Then, we establish characterizations of the Nash and egalitarian solutions on the basis of separability. Received: 12 August 2002, Revised: 22 March 2004, JEL Classification Numbers: C71, C78.Youngsub Chun: This work was supported by the Brain Korea 21 Project in 2003. I am grateful to William Thomson, a referee, and an associate editor for their valuable comments.     

ON THE NEUTRALITY OF COALITION FORMATION IN A PURE BARGAINING PROBLEM*

We consider the sequential bargaining game à la Stahl–Binmore–Rubinstein with random proposers, juxtaposing an ex ante coalition formation stage to their bargaining game. On the basis of the expected outcomes in the negotiation over how to split a dollar, players can form coalitions in a sequential manner, within each of which they can redistribute their payoffs. It turns out that the grand coalition does form, and that each player receives his discounted expected payoff, which is obtained by playing as a single player in the negotiation, although there could be many equilibria in the bargaining stage.     

Competitive bargaining equilibrium

In a simple exchange economy we propose a bargaining procedure that leads to a Walrasian outcome as the agents become increasingly patient. The competitive outcome therefore obtains even if agents have market power and are not price-takers. Moreover, where in other bargaining protocols the final outcome depends on bargaining power or relative impatience, the outcome here is determinate and depends only on preferences and endowments. Our bargaining procedure involves bargaining over prices and maximum quantity constraints, and it guarantees convergence to a Walrasian outcome for any standard exchange economy. In contrast, without quantity constraints we show that equilibrium is generically inefficient.     

Comparing Environmental Policy Instruments Within an Incomplete Contract Framework

This paper compares three different legal means—no environmental policy (the pollutee pays), full liability (the polluter pays), and pollution standards—to reduce and regulate neighborhood externalities within an incomplete contract framework. It turns out that the relative efficiency of these instruments depends, in general, on details. However, moderate standards are preferable to no environmental policy and tight (but not too tight) standards dominate liability. This provides under the given assumptions (neighborhood externalities, incomplete contracts) a justification for “sensible” standards for three reasons. First, unilateral allocations of property rights are biased that distort allocations even if ex post bargaining takes place. Second, a standard is superior in the following sense: if it is set equal to the outcome under any allocation of rights, it will be improved in the process of ex post bargaining. Third, unilateral property rights encourage strategic ex ante investments up to the point that committing to no bargaining would be beneficial (if possible).     

Endogenous wage bargaining institutions in oligopolistic sectors

Summary. This paper explores the endogenous emergence of wage bargaining institutions in a union-oligopoly framework. Technological asymmetries among firms are shown to be the driving force for the emergence of alternative wage bargaining centralization structures that are observable in real life. As wage deals at the sector-level obtain the consensus of all unions and the efficient firms, a regulator has an incentive to authorize those deals by activating/establishing a Minimum Sectoral Wage Institution(MSWI). If productivity differences are high enough, wage setting above the established wage floor may subsequently occur in efficient firms. Otherwise, a completely centralized wage bargaining structure emerges and the sector-level wage deal is simply confirmed as the firms wage rate. If, however, productivity asymmetries are rather insignificant, firms and unions have conflicting interests and a completely decentralized wage bargaining regime prevails in equilibrium.Received: 17 December 2001, Revised: 9 June 2003, JEL Classification Numbers: J50, J31, L13.Correspondence to: Emmanuel PetrakisParticular appreciation is expressed to an anonymous referee who has greatly helped us to improve our work upon an earlier draft of this paper. We also wish to thank T. Kollinzas, J. Padilla, H. Bester, J. Sakovics, K. Uwe-Kühn, J. J. Dolado, J. L. Ferreira, A. Matsui and C. Martinelli for their helpful comments and suggestions.     

Gender pairing and bargaining—Beware the same sex!

We study the influence of gender and gender pairing on economic decision making in an experimental two-person bargaining game where the other party’s gender is known to both actors. We find that (1) gender per se has no significant effect on behavior, whereas (2) gender pairing systematically affects behavior. In particular, we observe much more competition and retaliation and, thus, lower efficiency when the bargaining partners have the same gender than when they have the opposite gender. These findings are consistent with predictions from evolutionary psychology. Implications of our results for real-world organizations are discussed.     

Barriers to Global Free Trade through Bilateral Agreements

This paper examines the formation of bilateral free trade agreements (FTAs) in the context of a dynamic noncooperative bargaining game with a random proposer. We show that global free trade (a grand coalition) does not necessarily occur unless transfer payments among countries are allowed. When transfer payments are possible, bilateral FTAs always achieve global free trade, but the ex‐ante and ex‐post inequalities of social welfare among countries are larger than those when all countries are independent because of the strategic bargaining behavior.