Neutrality in arrow and other impossibility theorems

Summary. Although not assumed explicitly, we show that neutrality plays an important role in Arrow and other impossibility theorems. Applying it to pivotal voters we produce direct proofs of classical impossibility theorems, including Arrow's, as well as extend some of these theorems. We further explore the role of neutrality showing that it is equivalent to Pareto or reverse Pareto, and to effective dictatorship for non-null social welfare functions satisfying the principle of independence of irrelevant alternatives. It is also equivalent to Wilson's Citizens' Sovereignty--which is related to the intuition that symmetry over alternatives makes social preference depend only on citizens' preferences. We show that some of these results are more fundamental than others in that they extend both to infinite societies and to considerably smaller domains of preferences. Finally, as an application of Arrow's theorem, we provide a simple proof of the Gibbard-Satterthwaite theorem.Received: 13 April 2000, Revised: 6 December 2002, JEL Classification Numbers: D71, C70.I thank Salvador Barberá, Luis Corchón, Cesar Martinelli, Eric Maskin, Tomas Sjöström, Ricard Torres, José Pedro Ubeda, and an anonymous referee for feedback. The proofs of Arrow's theorem and two Wilson's theorems come from a note I wrote in 1987 at Universitat Autónoma de Barcelona (Ubeda [16]). In 1996 Geanakoplos [7] wrote a proof of Arrow's theorem similar but not identical to mine. All work in this paper is independent of his.     

A KKM-result and an application for binary and non-binary choice functions

Summary. By generalizing the classical Knaster-Kuratowski-Mazurkiewicz Theorem, we obtain a result that provides sufficient conditions to ensure the non-emptiness of several kinds of choice functions. This result generalizes well-known results on the existence of maximal elements for binary relations (Bergstrom [4]; Walker [16]; Tian [15]), on the non-emptiness of non-binary choice functions (Nehring [12]; Llinares and Sánchez [9]) and on the non-emptiness of some classical solutions for tournaments (top cycle and uncovered set) on non-finite sets. Received: December 29, 1999; revised version: October 18, 2001     

A dictatorial domain for monotone social choice functions

We give a dictatorial domain for monotone and unanimous social choice functions.     

Strategy-proof and individually rational social choice functions for public good economies: A note

Summary. Serizawa [3] characterized the set of strategy-proof, individually rational, no exploitative, and non-bossy social choice functions in economies with pure public goods. He left an open question whether non-bossiness is necessary for his characterization. We will prove that non-bossiness is implied by the other three axioms in his characterization. Received: October 17, 1997; revised version: January 19, 1998     

Strategy-proof contract auctions and the role of ties

A contract auction establishes a contract between a center and one of the bidders. As contracts may describe many terms, preferences over contracts typically display indifferences. The Qualitative Vickrey Auction (QVA) selects the best contract for the winner that is at least as good for the center as any of the contracts offered by the non-winning players. When each bidder can always offer a contract with higher utility for the center at an arbitrarily small loss of her own utility, the QVA is the only mechanism that is individually rational, strategy-proof, selects stable outcomes, and is Pareto efficient. For general continuous utility functions, a variant of the QVA involving fixed tie-breaking is strategy-proof and also selects stable outcomes. However, there is no mechanism in this setting that in addition also selects Pareto efficient outcomes.     

Voting on social security: Evidence from OECD countries

We test the subset of models of public choice of social security that have empirical predictions. The data, collected for this paper from the OECD countries for the years 1960, 1970, 1980, and 1990, provide some support for each of the theories. Higher median voter age, more income heterogeneity, greater similarity in family size, and variables that make a public pension program more profitable are all associated with a larger program. However, none of the theories explains why the shape of the age distribution and the time trend are so important. The results are robust under both fixed effects and random effects estimation.     

Majority Rule in a Stochastic Model of Bargaining

In this paper we consider multilateral stochastic bargaining models with general agreement rules. For n-player games where in each period a player is randomly selected to allocate a stochastic level of surplus and q?n players have to agree on a proposal to induce its acceptance, we characterize the set of stationary subgame perfect equilibrium payoffs and establish their existence. We show that for agreement rules other than the unanimity rule, the equilibrium payoffs need not be unique. Furthermore, even when the equilibrium is unique, it need not be efficient. Journal of Economic Literature Classification Numbers: C73, C78, D70.     

The role of risk and risk-aversion in adoption of alternative marketing arrangements by the US farmers

The objective of this article is to analyse the relationship between farmers’ risk-aversions and the riskiness of various agricultural enterprises to see which marketing arrangements would typically emerge. Relying on the basic agency theory model, we hypothesize the prevalence of alternative marketing arrangements (AMAs) in situations with high risk-averse farmers and high-risk enterprises and the prevalence of spot (cash) markets for low risk-averse participants and less risky enterprises. Our empirical tests are carried out using the 2004 Agricultural Resource Management Survey (ARMS). The empirical results are largely supportive of the agency theory of contract choice.     

Preferences for alternative fuel vehicles of company car drivers

Costs of car ownership for company cars drivers and private car owners are very different. Car use, car choice decisions and preferences for car characteristics may therefore differ substantially between these two markets. In this paper, we present results of a study on the preferences of company car drivers for alternative fuel vehicles and their characteristics, based on data from an online stated choice experiment in the Netherlands. Results show that, assuming current car characteristics, preferences for alternative fuel vehicles, and for electric and fuel cell cars in particular, are substantially lower than those for the conventional technology. Limited driving ranges, long recharge/refuelling times and limited availability of refuelling opportunities, are to a large extent responsible for this. Preferences for alternative fuel vehicles increase considerably with improvements on these aspects, especially for the hybrid and flexifuel car. Under the current company car tax system in the Netherlands, which favours cleaner technologies, these two car types are even preferred to the conventional technology, assuming equal catalogue prices and personal monthly cost contributions. Comparing results with those from a similar choice experiment among private car owners shows that willingness to pay patterns for AFV improvements regarding driving range, recharge and refuelling times, fuel availability and diversity in AFV supply, are considerably different for company car drivers than for private car owners. Company and private car drivers may therefore react (very) differently to future improvements in AFV technology and fuel availability. We finally show that preferences of company car drivers for fuel cell and electric cars depend to a large extent on annual mileage. Market share simulations show that potential early adopters of electric and fuel cell cars can be found among people with a relatively low annual mileage.     

A test of the rational expectations hypothesis using data from a natural experiment

Data on contestants’ choices in Italian Game Show Affari Tuoi are analysed in a way that separates the effect of risk attitude (preferences) from that of beliefs concerning the amount of money that will be offered to contestants in future rounds. This separate identification is possible by virtue of the fact that, at a certain stage of the game, beliefs are not relevant, and risk attitude is the sole determinant of choice. The rational expectations hypothesis is tested by comparing the estimated belief function with the ‘true’ offer function which is estimated extraneously using data on offers actually made to contestants. We find a close correspondence, leading us to accept the rational expectations hypothesis. The importance of belief formation is confirmed by the estimation of a mixture model which establishes that the vast majority of contestants are forward looking as opposed to myopic.     

High school experiences,the gender wage gap,and the selection of occupation

Using within-high-school variation and controlling for a measure of cognitive ability, this article finds that high-school leadership experiences explain a significant portion of the residual gender wage gap and selection into management occupations. Our results imply that high-school leadership could build non-cognitive, productive skills that are rewarded years later in the labour market and that explain a portion of the systematic difference in pay between men and women. Alternatively, high-school leadership could be a proxy variable for personality characteristics that differ between men and women and that drive higher pay and becoming a manager. Because high-school leadership experiences are exogenous to direct labour market experiences, our results leave less room for direct labour market discrimination as a driver of the gender wage gap and occupation selection.     

The likelihood of the referendum paradox for a given referendum result

The referendum (or compound majority) paradox occurs when the majority of voters in the majority of districts supports an issue/candidate but the majority of voters across all districts opposes the same issue/candidate (or vice versa). We calculate the likelihood of this social choice anomaly for any (possibly large) odd number of districts and any (possibly large) odd number of voters per district. The likelihood of the paradox is close to 50% when the issue/candidate is divisive (voters across all districts are split almost 50%–50%). The paradox virtually disappears when the issue/candidate is supported/opposed by at least two-thirds of all voters.     

A Humean theory of choice of which rationality may be one consequence

For the reader who considers economic theory of choice as a special case of a more general theory of action, Hume's discussion of the determinants of action in the Treatise of Human Nature (1739?–?40), in the Enquiry on Human Understanding (1748) and in the Dissertation on Passions (1757) deserves attention. However, according to some modern commentators, Hume does not seem to have given any evidence that would favour what nowadays we would consider as the kind of rationality involved in modern theories of rational choice. On the contrary, this paper arrives at the conclusion that consistency between preferences and choice, like the usual properties of completeness and transitivity, may be considered as outcomes of a mental process, described by means of a decision algorithm that aims to represent Hume's theory of choice.     

A characterization of social choice correspondences that implement the core of simple games

In a coalitional voting game, an alternative is said to be in the core when no majority is willing to replace it with another alternative. A social choice correspondence is a mapping which associates any profile of voters’ preferences with a non-empty subset of the set of alternatives, which is understood as the set of selected outcomes. We characterize the social choice correspondences which always select the core of a simple game for any profile of preferences. This work was completed when B. Tchantcho was Visiting assistant Professor at UTA (University of Texas at Arlington). We acknowledge the support of the Department of Mathematics of UTA. We are most grateful to R. Pongou of Brown University, USA for his help and advice. We sincerely thank N.G Andjiga for his helpful comments and we are indebted to two anonymous referees for their helpful comments.     

The future of development economics: a methodological agenda

This paper discusses methodological differences between universalismand particularism in development economics by focusing on the‘East Asian Miracle’ debate. It proposes to builddevelopment economics as part of hetero-economics, not mono-economics,following Max Weber's methodology of social science, and suggestsdeveloping intermediate theories by abstracting directly fromgiven comparative settings. It also discusses the limitationsthat are inherent in this method, as well as ways to employthe method in actual analyses. This paper argues that the futuretask of development economics lies in recombining existing theoriesand developing new, complementing theories that will systematicallydelineate the diversity of developing countries.     

Nonlinear behavior of the socio-economic dynamics for lake eutrophication control

To succeed in combating lake eutrophication, cooperation of local inhabitants, small factories, and farmers in reducing phosphorus discharge is very important. But the willingness of each player to cooperate would depend on the cooperation of other players and on the level of environmental concern of the society in general. Here we study the integrated dynamics of people's choice of behavior and the magnitude of eutrophication. Assumptions are: there are a number of players who choose between alternative options: a cooperative and environment-oriented option is more costly than the other. The decision of each player is affected by “social pressure” as well as by economical cost of the options. The lake pollution increases with the total phosphorus released, and a high pollution level in the lake would enhance the social pressure. The model includes a positive and a negative feedback loops which create diverse dynamical behavior. The model often shows bistability — having an equilibrium with a high level of cooperation among people and clean water, and the other equilibrium with low cooperation and polluted water, which are simultaneously stable. The model also shows fluctuation between a high and a low levels of cooperation in alternating years, cycle with a longer periodicity, or chaotic fluctuation. Conservatism of people stabilizes the system and sometimes helps maintaining cooperation. The system may show unexpected parameter dependence — the improved phosphorus removing efficiency might make water more polluted if it causes the decline in the environmental concern and cooperation among people.     

Qualitative valuation of environmental criteria through a group consensus based on stochastic dominance

This paper introduces a qualitative valuation method to elicit stakeholders' intensities of preferences for a complex environmental issue and multiple social groups. Environmental valuation studies have shown that in any complex environment with a diversity of environmental services, stakeholders have difficulties using a monetary valuation to make trade-offs between different environmental services. Stated preference methods such as the Contingent Valuation Method (CVM) have been criticised for their individualistic format and assumptions of commensurability between environmental criteria. To alleviate both of these criticisms, we propose a qualitative valuation method. The method contains a discursive step to allow stakeholders to discuss and construct a list of environmental criteria and alternative plans. The list of criteria and plans is subsequently used by a group of experts to formulate an Impact Matrix (IM), which is to be used in the succeeding individualistic steps of the methodology. The first individualistic step consists of asking the stakeholders to rank Alternative Impacts (AIs) in the IM for each single criterion. The stakeholders are then asked to express intensities of their preferences through pairwise comparisons between the AIs of the constructed rank order on each single criterion. These intensities are expressed on a qualitative scale. Subsequently, to provide social intensities of preferences, a social preference (social rank order) is first determined for each single criterion. We propose to use the median value among the intensities of preferences as the social intensity of preference by assuming interpersonal comparability and taking into account stochastic monotonocity. This is a pre-processing step, which allows us to reach social intensities of preferences in the Lar rangeland (Iran), where several social groups have conflicting interests on rangeland services, leading to conflicting preferences on environmental criteria.     

The bioeconomics of homogeneous middleman groups as adaptive units: Theory and empirical evidence viewed from a group selection framework

The paper presents a bioeconomics theory of homogeneous middleman groups (HMGs) as adaptive units as well as empirical evidence in the form of a number of historical case studies of HMGs functioning as adaptive units in less-developed economies lacking infrastructure. The evidence presented is not new: most of the case studies have been published [Landa (in Jenkins (Ed.) The informal sector: Including the excluded, 1988)]. What is new, however, is analyzing the phenomena of HMGs in a new way—as adaptive units viewed from a group selection perspective. In doing so, the case studies in this paper present empirical evidence of the existence and importance of group selection in human society. Target paper.     

The probability of violating Arrow’s conditions

Arrow’s impossibility theorem shows that all preference aggregation rules (PARs) must violate a specific set of normative conditions (transitivity, Pareto, IIA, nondictatorship) over an unrestricted domain of preference profiles. However, the theorem does not address which PARs are more likely to violate those conditions across preference profiles. We compare the probabilities that thirteen PARs (anti-plurality, Hare, Nanson, plurality, plurality runoff, Simpson–Kramer, Baldwin, Borda, Coombs, Copeland, Dowdall, pairwise majority, and ranked pairs) violate Arrow’s conditions. We prove that Baldwin, Borda, Coombs, Copeland, Dowdall, and ranked pairs are less likely to violate IIA than the first six PARs, and they are less likely to violate Arrow’s conditions jointly. In contrast, pairwise majority never violates IIA but can violate transitivity. Simulations with three alternatives reveal that among the PARs studied, pairwise majority is the most likely to satisfy Arrow’s conditions jointly. Our results suggest pairwise majority violates transitivity with a small probability, while the other PARs violate IIA with much larger probabilities.