A characterization of the Nash bargaining solution

We characterize the Nash bargaining solution replacing the axiom of Independence of Irrelevant Alternatives with three independent axioms: Independence of Non-Individually Rational Alternatives, Twisting, and Disagreement Point Convexity. We give a non-cooperative bargaining interpretation to this last axiom. Received: 4 September 2000/Accepted: 6 September 2001     

Characterizing the Nash bargaining solution without Pareto-Optimality

We consider the bargaining problems with a variable number of agents. Lensberg had previously characterized the Nash solution as the only solution to satisfy the following axioms: Pareto-Optimality, Symmetry, Scale Invariance, and Multilateral Stability. We show that the disagreement solution is the only additional solution to satisfy the restricted list of axioms obtained by dropping Pareto-Optimality.Support from NSF under grant 8511136 is gratefully acknowledged. Thanks are also due to H. Moulin for his comments at an early stage of this research.     

Distributive justice and the Nash bargaining solution

Suppes-Sen dominance or SS-proofness (SSP) is a commonly accepted criterion of impartiality in distributive justice. Mariotti (Review of Economic Studies, 66, 733–741, 1999) characterized the Nash bargaining solution using Nash’s (Econometrica, 18, 155–162, 1950) scale invariance (SI) axiom and SSP. In this article, we introduce equity dominance (E-dominance). Using the intersection of SS-dominance and E-dominance requirements, we obtain a weaker version of SSP (WSSP). In addition, we consider α ? SSP, where α measures the degree of minimum acceptable inequity aversion; α ? SSP is weaker than weak Pareto optimality (WPO) when α = 1. We then show that it is still possible to characterize the Nash solution using WSSP and SI only or using α -SSP, SI, and individual rationality (IR) only for any \({\alpha \in [0,1)}\). Using the union of SS-dominance and E-dominance requirements, we obtain a stronger version of SSP (SSSP). It turns out that there is no bargaining solution that satisfies SSSP and SI, but the Egalitarian solution turns out to be the unique solution satisfying SSSP.     

Weakest collective rationality and the Nash bargaining solution

We propose a new axiom, weakest collective rationality (WCR) which is weaker than both weak Pareto optimality (WPO) in Nash’s (Econometrica 18:155–162, 1950) original characterization and strong individual rationality (SIR) in Roth’s (Math Oper Res 2:64–65, 1977) characterization of the Nash bargaining solution. We then characterize the Nash solution by symmetry (SYM), scale invariance (SI), independence of irrelevant alternatives (IIA) and our weakest collective rationality (WCR) axiom.     

A universal meta bargaining implementation of the Nash solution

This paper follows van Damme (1986) in presenting a meta bargaining approach that justifies the Nash bargaining solution. But in contrast to van Damme's procedure our meta bargaining game is universal in the sense that all bargaining solutions are allowed as strategic choices in the meta bargaining game. Also our result holds true for any number n of players. Received: 31 July 2000/Accepted: 19 March 2001     

Nash implementation and the bargaining problem

We study Nash implementation of the bargaining solutions in a cake sharing set up. We argue that the minimal Pareto optimal, symmetric and Nash implementable SBS is the one inducing all Pareto optimal and midpoint-dominating utility vectors in each state.     

An arbitration game and the egalitarian bargaining solution

We analyze a simple arbitration procedure which is a multi-stage variant of Nash's demand game. In the absence of discounting, all Nash equilibria of the game yield the egalitarian solution in the first stage. The crucial feature of our arbitration procedure is that, in the case of incompatible demands, the game is allowed to continue and the player who demands the higher gain over the disagreement point is penalized by restricting her or his feasible demands in the following stage. Suitable modifications of the arbitration game yield the lexicographic extension of the egalitarian solution, resp. the proportional solutions. Journal of Economic Literature Classification Numbers: C72, C78.Financial support through grants from the Social Sciences and Humanities Research Council of Canada and the University of Waterloo is gratefully acknowledged. Earlier versions of the paper were presented at McMaster University and Brock University. The authors thank Nejat Anbarci, Michele Piccione, Venkatraman Sadanand, an editor, and the referees for their useful comments.     

An axiomatization of the Kalai-Smorodinsky solution when the feasible sets can be finite

We axiomatize the Kalai-Smorodinsky solution (1975) in the Nash bargaining problems if the feasible sets can be finite. We show that the Kalai-Smorodinsky solution is the unique solution satisfying Continuity (in the Hausdorff topology endowed with payoffs space), Independence (which is weaker than Nash's one and essentially equivalent to Roth (1977)'s one), Symmetry, Invariance (both of which are the same as in Kalai and Smorodinsky), and Monotonicity (which reduces to a little bit weaker version of the original if the feasible sets are convex). Received: 4 November 1999/Accepted: 6 June 2001     

An axiomatization of success

In this paper we give an axiomatic characterization of a family of measures of success defined by Laruelle and Valenciano (Soc Choice Welf 27:171–197, 2005) for voting rules.     

A Nash bargaining model for simple exchange networks

Starting from exogenously given negotiation networks, sociological exchange theories explain bilateral divisions of fixed surpluses (e.g., cake, dollar) as consequences of the partners’ structural embeddedness. In accordance with the available experimental evidence, we focus on simple exchange networks and present a formal model for predicting profit splits from such structures. In contrast to other approaches, we combine the generalized Nash bargaining solution from game theory with the assumption that both relational features and network positions affect exchange outcomes. The resulting point predictions for profit splits correspond closely with experimental results obtained by Cook et al. [Cook, K.S., Emerson, R.M., Gillmore, M.R., Yamagishi, T., 1983. The distribution of power in exchange networks: theory and experimental results. American Journal of Sociology 89, 275–305], Lovaglia et al. [Lovaglia, M.J., Skvoretz, J., Willer, D., Markovsky, B., 1995. Negotiated exchanges in social networks. Social Forces 74, 123–155], Markovsky et al. [Markovsky, B., Willer, D., Patton, T., 1988. Power relations in exchange networks. American Sociological Review 53, 220–236], Simpson and Willer [Simpson, B., Willer, D., 1999. A new method for finding power structures. In: Willer, D. (Ed.), Network Exchange Theory. Praeger, Westport, CT, pp. 270–284], Skvoretz and Fararo [Skvoretz, J., Fararo, T.J., 1992. Power and network exchange: an essay toward theoretical unification. Social Networks 14, 325–344], Skvoretz and Willer [Skvoretz, J., Willer, D., 1993. Exclusion and power: a test of four theories of power in exchange networks. American Sociological Review 58, 801–818] as well as Yamagishi et al. [Yamagishi, T., Gillmore, M.R., Cook, K.S., 1988. Network connections and the distribution of power in exchange networks. American Journal of Sociology 93, 833–851].     

Nash bargaining theory when the number of alternatives can be finite

Nash (1950) considered a domain of convex bargaining problems. We analyse domains including, or even consisting of, finite problems and provide various characterisations of the Nash Bargaining Solution (NBS). In particular, we extend Kaneko's (1980) results. Received: 12 July 1996 / Accepted: 6 February 1997     

An axiomatization of the human development index

In 2010 the UNDP unveiled a new methodology for the calculation of the Human Development Index (HDI). In this paper I investigate the normative and practical properties of this change vis a vis the original formulation of the HDI in 1990. The main conceptual innovation of the new index can be summarized as follows: the new HDI penalizes both low and uneven achievements across all dimensions of human development, whereas the old formulation is not sensitive to such uneven development. In practice, however, both methodologies agree considerably in terms of how they rank countries, but when they differ, the new methodology produces results more consistent with what the HDI is intended to measure: human development and capabilities, as conceptualized by Sen (Commodities and capabilities. Elsevier, Oxford 1985).     

Maximal symmetry and the Nash solution

The Nash Bargaining Solution is characterised by using the new axiom of Maximal Symmetry in place of Nash's Independence of Irrelevant Alternatives and Symmetry. This axiom expresses the idea that a fair arbitrator should treat symmetric alternatives in the same way, subject to the feasibility constraint. An advantage of the proposed characterisations is that they are valid on a wide set of domains, in particular domains including, or consisting of, non-convex problems. Received: 16 March 1998/Accepted: 13 October 1998     

Twofold optimality of the relative utilitarian bargaining solution

Given a bargaining problem, the relative utilitarian (RU) solution maximizes the sum total of the bargainer’s utilities, after having first renormalized each utility function to range from zero to one. We show that RU is “optimal” in two very different senses. First, RU is the maximal element (over the set of all bargaining solutions) under any partial ordering which satisfies certain axioms of fairness and consistency; this result is closely analogous to the result of Segal (J Polit Econ 108(3):569–589, 2000). Second, RU offers each person the maximum expected utility amongst all rescaling-invariant solutions, when it is applied to a random sequence of future bargaining problems generated using a certain class of distributions; this is recalls the results of Harsanyi (J Polit Econ 61:434–435, 1953) and Karni (Econometrica 66(6):1405–1415, 1998).     

A solution for two-person bargaining problems

Everyday bargaining problems are often solved by tossing a coin. A solution for two-person bargaining problems is axiomatized, which is a Pareto-optimal generalization of this coin tossing method. The super-additive solution of Perles and Maschler is also shown to be a generalization of this method. Various properties of our solution are studied, including continuity and risk sensitivity, and compared with properties of other solutions discussed in the literature.This study was financed by the Yrjö Jahnsson Foundation, which is gratefully acknowledged. I like to thank an anonymous referee for useful comments.     

An axiomatization of the core for finite and continuum games

We provide a new axiomatization of the core of games in characteristic form. The games may have either finite sets of players or continuum sets of players and finite coalitions. Our research is based on Peleg's axiomatization for finite games and on the notions of measurement-consistent partitions and the f-core introduced by Kaneko and Wooders. Since coalitions are finite in both finite games and in continuum games, we can use the reduced game property and the converse reduced game property for our axiomatization. Both properties are particularly appealing in large economies.This paper is a revision of University of Bonn Sonderforschungsbereich 303 Discussion Paper No. B-149, with the same title.     

The ordinal egalitarian bargaining solution for finite choice sets

Rubinstein et al. (Econometrica 60:1171–1186, 1992) introduced the Ordinal Nash Bargaining Solution. They prove that Pareto optimality, ordinal invariance, ordinal symmetry, and IIA characterize this solution. A feature of their work is that attention is restricted to a domain of social choice problems with an infinite set of basic allocations. We introduce an alternative approach to solving finite social choice problems using a new notion called the Ordinal Egalitarian (OE) bargaining solution. This suggests the middle ranked allocation (or a lottery over the two middle ranked allocations) of the Pareto set as an outcome. We show that the OE solution is characterized by weak credible optimality, ordinal symmetry and independence of redundant alternatives. We conclude by arguing that what allows us to make progress on this problem is that with finite choice sets, the counting metric is a natural and fully ordinal way to measure gains and losses to agents seeking to solve bargaining problems.     

Disagreement point monotonicity,transfer responsiveness,and the egalitarian bargaining solution

This paper provides an axiomatization of the egalitarian bargaining solution. The central axiom used (together with some standard properties of bargaining solutions) in this characterization is a transfer responsiveness condition. First, it ensures that no transfer paradox can occur if bargaining power is transferred from one agent to another by decreasing one agent's and increasing the other agent's component of the disagreement point. Second, the extent of external effects of such a transfer is limited by requiring that agents not involved in the transfer neither gain more than the winner nor lose more than the loser of the transfer. Journal of Economic Literature Classification No.: C78.I thank William Thomson whose comments on an earlier version led to substantial improvements.     

Endogenous reference points and the adjusted proportional solution for bargaining problems with claims

 A modification of the proportional solution for bargaining problems with claims is proposed. This solution is constructed by considering an endogenous reference point. Characterization results of the aforementioned solution are provided. Received: 22 December 1993/Accepted: 12 August 1996     

Walking the talk in multiparty bargaining: An experimental investigation

We study the framing effects of communication on payoffs in multiparty bargaining. Communication has been shown to be more truthful and revealing than predicted in equilibrium. Because talk is preference-revealing, it may effectively frame bargaining around a logic of fairness or competition, moving parties on a path toward or away from equal-division agreements. These endogenous framing effects may outweigh any overall social utility effects due to the mere presence of communication. In two studies, we find that non-binding talk about fairness within a three-party, complete-information game leads toward off-equilibrium, equal division payoffs, while non-binding talk focusing on Competitive Reasoning moves parties away from equal divisions. Our two studies allow us to demonstrate that manipulated pre-game talk and spontaneous within-game dialogue lead to the same results.