An efficiency characterization of plurality rule in collective choice problems

We consider the problem of selecting alternatives from a set of feasible alternatives over which each agent is endowed with a strict preference. We show that there is one and only one rule that satisfies anonymity, neutrality, efficiency, tops-only, and reinforcement. The rule is known as plurality rule, which selects the alternative(s) most preferred by the largest number of agents. I would like to thank William Thomson for helpful suggestions and discussions. I am grateful to Biung-Ghi Ju, Hyungjun Kim, and Yan-An Hwang for detailed comments. I am also indebted to the Editor and an anonymous referee for valuable suggestions. As usual, I am responsible for any remaining deficiency.     

Feasible elimination procedures in social choice: An axiomatic characterization

Feasible elimination procedures (Peleg, 1978) play a central role in constructing social choice functions which have the following property: in the associated game form, for any preference profile there exists a strong Nash equilibrium resulting in the sincere outcome. In this paper we provide an axiomatic characterization of the social choice correspondences resulting from applying feasible elimination procedures. The axioms are anonymity, Maskin monotonicity, and independent blocking. We also show that these axioms are logically independent.     

A simple characterization of majority rule

Summary. Assuming an odd number of voters, E. S. Maskin recently provided a characterization of majority rule based on full transitivity. This paper characterizes majority rule with a set of axioms that includes two of Maskin's, dispenses with another, and contains weak versions of his other two axioms. It allows the number of voters to be odd or even. Received: December 23, 1998; revised version: May 10, 1999     

Economists,social reformers,and prophets: a feminist critique of economic efficiency

This article examines the concept of Pareto optimality, bringing to light some of its implicit assumptions about the nature of human agency, work, and gender. It explores the androcentric character of the economic agent and the gendered nature of neoclassical models in relation to the historical development of the concept of economic efficiency during the late 1930s. The thrust toward the development of Pareto optimality as a scientific criterion of economic welfare was a response to the methodological tensions between the clearly political nature of economics and the scientific aspirations of economists. An examination of the debates from this period illuminates some of the values that became embedded in neoclassical economics, and which are now hidden by the masks of mathematics and abstraction.     

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.     

A leximin characterization of strategy-proof and non-resolute social choice procedures

Summary. We characterize strategy-proof social choice procedures when choice sets need not be singletons. Sets are compared by leximin. For a strategy-proof rule g, there is a positive integer k such that either (i) the choice sets g(r) for all profiles r have the same cardinality k and there is an individual i such that g(r) is the set of alternatives that are the k highest ranking in i's preference ordering, or (ii) all sets of cardinality 1 to k are chosen and there is a coalition L of cardinality k such that g(r) is the union of the tops for the individuals in L. There do not exist any strategy-proof rules such that the choice sets are all of cardinality to k where . Received: November 8, 1999; revised version: September 18, 2001     

An extreme point characterization of random strategy-proof social choice functions: The two alternative case

We show that every strategy-proof random social choice function is a convex combination of strategy-proof deterministic social choice functions in a two-alternative voting model. This completely characterizes all strategy-proof random social choice functions in this setting.     

The structure of strategy-proof social choice — Part I: General characterization and possibility results on median spaces

We define a general notion of single-peaked preferences based on abstract betweenness relations. Special cases are the classical example of single-peaked preferences on a line, the separable preferences on the hypercube, the “multi-dimensionally single-peaked” preferences on the product of lines, but also the unrestricted preference domain. Generalizing and unifying the existing literature, we show that a social choice function is strategy-proof on a sufficiently rich domain of generalized single-peaked preferences if and only if it takes the form of voting by issues (“voting by committees”) satisfying a simple condition called the “Intersection Property.”Based on the Intersection Property, we show that the class of preference domains associated with “median spaces” gives rise to the strongest possibility results; in particular, we show that the existence of strategy-proof social choice rules that are non-dictatorial and neutral requires an underlying median space. A space is a median space if, for every triple of elements, there is a fourth element that is between each pair of the triple; numerous examples are given (some well-known, some novel), and the structure of median spaces and the associated preference domains is analysed.     

An analysis of the impact of unionization on efficiency: evidence from a meta-frontier analysis

This article examines the impact of unions on the efficiency of establishments in the manufacturing industry by comparing the results from two different empirical strategies: stochastic frontier analysis (SFA) and meta-frontier analysis (MFA). While SFA concludes that union establishments show higher technological efficiency, the results are the opposite when estimating production functions with MFA. In SFA, unionized establishments appear to be more efficient because they remain closer to their own production frontier; however, in MFA – where groups with heterogeneous technology can be compared – we find that nonunionized establishments are more efficient because they are closer to the meta-frontier than their unionized counterparts.     

改进交易效率的农业生产性服务业发展机理与实证研究

基于劳动分工理论与超边际分析方法,构建改进交易效率的农业生产性服务业发展模型,运用面板数据模型对理论模型进行了实证检验。研究发现:商品市场交易效率、农户数量规模、政府补贴和农户劳动力变化是影响改进交易效率的农业生产性服务业发展的四个因素。其中,商品市场交易效率对改进交易效率的农业生产性服务业发展不具有显著正向影响,农户分布密度、政府补贴和城镇化率提高1%,改进交易效率的农业生产性服务业发展水平分别提高0.135、0.955和2.714。