Identification of domain restrictions over which acyclic, continuous-valued, and positive responsive social choice rules operate

We consider a social choice problem in various economic environments consisting of n individuals, 4≤n<+∞, each of which is supposed to have classical preferences. A social choice rule is a function associating with each profile of individual preferences a social preference that is assumed to be complete, continuous and acyclic over the alternatives set. The class of social choice rules we deal with is supposed to satisfy the two conditions; binary independence and positive responsiveness. A new domain restriction for the social choice rules is proposed and called the classical domain that is weaker than the free triple domain and holds for almost all economic environments such as economies with private and/or public goods. In this paper we explore what type of classical domain that admits at least one social choice rule satisfying the mentioned conditions to well operate over the domain. The results we obtained are very negative: For any classical domain admitting at least one social choice rule to well operate, the domain consists only of just one profile.     

Strongly implementable social choice correspondences and the supernucleus

In this paper, we present a characterization of social choice correspondences which can be implemented in strong Nash equilibrium, stated in terms of the power structure implicit in the social choice rule. We extend the notion of an effectivity function to allow for simultaneous vetoing by several coalitions. This leads to the concept of a domination structure as a generalized effectivity function.  Using this concept and a solution known from the theory of effectivity functions, the supernucleus, we give a characterization of strongly implementable social choice correspondences as supernucleus correspondence relative to an appropriate domination structure. Received: 2 February 1996/Accepted: 2 February 1998     

Strategy-proofness and markets

If a market is considered to be a social choice function, then the domain of admissible preferences is restricted and standard social choice theorems do not apply. A substantial body of analysis, however, strongly supports the notion that attractive strategy-proof social choice functions do not exist in market settings. Yet price theory, which implicitly assumes the strategy-proofness of markets, performs quite well in describing many real markets. This paper resolves this paradox in two steps. First, given that a market is not strategy-proof, it should be modeled as a Bayesian game of incomplete information. Second, a double auction market, which is perhaps the simplest operationalization of supply and demand as a Bayesian game, is approximately strategy-proof even when the number of traders on each side of the market is quite moderate. Received: 24 March 1999/Accepted: 25 October 1999     

On fairness and welfare analysis under uncertainty

This paper investigates the role of fairness, uncertainty, and a “veil of ignorance” in efficient resource allocation. It focuses on the choice of private and public goods, the method of financing, as well as the choice of information available for public decision-making. A fair-equivalent and Pareto efficient allocation is presented using a maximin criterion defined in terms of individual willingness-to-pay. The paper investigates the role of information in public decision making in terms of its implications for both efficiency and fairness. While better information typically generates improved efficiency, it can also contribute to unfair allocations. The effects of asymmetric information are discussed. Received: 4 May 1998/Accepted: 28 February 2002 We would like to thank two anonymous referees for very useful comments on an earlier draft of the paper. The research was supported in part by a Hatch grant from the University of Wisconsin, Madison.     

Pairwise Strategy-Proofness and Self-Enforcing Manipulation

“Strategy-proofness” is one of the axioms that are most frequently used in the recent literature on social choice theory. It requires that by misrepresenting his preferences, no agent can manipulate the outcome of the social choice rule in his favor. The stronger requirement of “group strategy-proofness” is also often employed to obtain clear characterization results of social choice rules. Group strategy-proofness requires that no group of agents can manipulate the outcome in their favors. In this paper, we advocate “effective pairwise strategy-proofness.” It is the requirement that the social choice rule should be immune to unilateral manipulation and “self-enforcing” pairwise manipulation in the sense that no agent of a pair has the incentive to betray his partner. We apply the axiom of effective pairwise strategy-proofness to three types of economies: public good economy, pure exchange economy, and allotment economy. Although effective pairwise strategy-proofness is seemingly a much weaker axiom than group strategy-proofness, effective pairwise strategy-proofness characterizes social choice rules that are analyzed by using different axioms in the literature.     

To be or not to be involved: a questionnaire-experimental view on Harsanyi’s utilitarian ethics

According to standard theory founded on Harsanyi (J Polit Econ 61:434–435, 1953; 63:309–321, 1955) a social welfare function can be appropriately based on the individual’s approach to choice under uncertainty. We investigate how people really do rank distributions in terms of welfare. According to Harsanyi, the evaluation can be done from the standpoint of an uninvolved external judge, a public official, for example, or by a person who knows that she holds one of the positions in society, with an equal chance for any of the available positions. Are these two structures to be viewed differently? We use a questionnaire experiment to focus on the two different interpretations of the Harsanyi approach. There are important, systematic differences that transcend the cultural background of respondents.     

Approval Voting on Dichotomous Preferences

The aim of this paper is to find normative foundations of Approval Voting when individuals have dichotomous preferences. We show that a social choice function is anonymous, neutral, strategy-proof and strictly monotone if and only if it is Approval Voting and interpret this result as an extension of May’s theorem (Econometrica 20:680–684, 1952). Then, we show that Approval Voting is the only strictly symmetric, neutral and efficient social choice function. This result is related to a characterization of Baigent and Xu (Math Soc Sci 21:21–29, 1991).     

Assent-maximizing social choice

We take a decision theoretic approach to the classic social choice problem, using data on the frequency of choice problems to compute social choice functions. We define a family of social choice rules that depend on the population’s preferences and on the probability distribution over the sets of feasible alternatives that the society will face. Our methods generalize the well-known Kemeny Rule. In the Kemeny Rule, it is known a priori that the subset of feasible alternatives will be a pair. We define a distinct social choice function for each distribution over the feasible subsets. Our rules can be interpreted as distance minimization—selecting the order closest to the population’s preferences, using a metric on the orders that reflects the distribution over the possible feasible sets. The distance is the probability that two orders will disagree about the optimal choice from a randomly selected available set. We provide an algorithmic method to compute these metrics in the case where the probability of a given feasible set is a function only of its cardinality.     

Characterization of self-selective social choice functions on the tops-only domain

Self-selectivity is a new kind of consistency pertaining to social choice rules. It deals with the problem of whether a social choice rule selects itself from among other rival such rules when a society is also to choose the choice rule that it will employ in making its choice from a given set of alternatives. Koray [3] shows that a neutral and unanimous social choice function is universally self-selective if and only if it is dictatorial. In this paper, we confine the available social choice functions to the tops-only domain and examine whether such restriction allow us to escape the dictatoriality result. A neutral, unanimous, and tops-only social choice function, however, turns out to be self-selective relative to the tops-only domain if and only if it is top-monotonic, and thus again dictatorial. Received: 8 October 2001/Accepted: 4 June 2002     

Minimal manipulability and interjacency for two-person social choice functions

This paper investigates the number of profiles at which a social choice function is manipulable. It is found that there is a lower bound on this number when the social choice function is assumed non-dictatorial. Also, any number between this lower bound and the maximal number of profiles may be obtained as the number of manipulable profiles of some social choice function. Received: 30 November 1993 / Accepted: 14 April 1997     

Locating libraries on a street

Hotelling (1929) studied two competing firms choosing their locations on a street. We consider instead a planner who builds two identical public facilities (e.g., libraries, parks, bridges, etc). We ask a normative question: Where should the planner build these facilities? We prove an axiomatic characterization of the efficient social choice rules that satisfy what is called the replacement-domination, which is a formulation of the idea of “solidarity” among the agents. Received: 26 November 1997/Accepted: 28 February 2000     

Multi-profile intergenerational social choice

In an infinite-horizon setting, Ferejohn and Page showed that any social welfare function satisfying Arrow’s axioms and stationarity must be a dictatorship of the first generation. Packel strengthened this result by proving that no collective choice rule generating complete social preferences can satisfy unlimited domain, weak Pareto and stationarity. We prove that this impossibility survives under a domain restriction and without completeness. We propose an alternative stationarity axiom and show that a social welfare function on a specific domain satisfies this modified version and some standard social choice axioms if and only if it is a chronological dictatorship.     

INFORMATIZATION AND PUBLIC ADMINISTRATION: A POLITICAL SCIENCE PERSPECTIVE

In recent years, both academic and policy making circles in the UK have shown a growing interest in the potential uses of information and communication technologies (ICTs) in the delivery of government services. Much of the academic literature has been centred around the concept of 'informatization', and it has been suggested that the new technologies are transforming public services. Key theorists in the field of Public Administration have argued that informatization is one of a number of major trends likely to shape public services in the twenty-first century. However, the dominant theoretical approaches within public administration- those rooted in political sciencesuggest that inertia and stability are the norm in the public sector; clearly there is something of a contradiction between these two broad approaches. This paper outlines three political science perspectives that might be used in analysing informatization: the policy networks approach, rational choice and the new institutionalism. Evidence is then drawn from the social security, health care and social care sectors of the British public sector and related to the political science frameworks in order to examine their utility. Not only do these frameworks rightly highlight the incremental nature of change, but they also help to explain important variations in ICT use across the three policy sectors. It is concluded that combining the study of informatization and political science offers a fruitful avenue for future research.     

Integrating Power? Evaluating Public Relations Influence in an Integrated Communication Structure

The emerging integrated environment for communication functions has put public relations in a potentially compromising position. In particular, literature reviews reveal scholar concerns about an inferior technical role for public relations practitioners. The question of integrating communications may be a question of power: whether the public relations function enacts influence, authority, or capacity to affect decision-making within an integrated organization. This study explores perceptions of 20 public relations professionals in an integrated communication structure. Results show that public relations may gain the ability to enact influence through social media acumen and the interconnected structure of communications, in which practitioner expertise, information, and knowledge may lead to more influence.     

Crime, policing and social order: on the expressive nature of public confidence in policing

Public confidence in policing is receiving increasing attention from UK social scientists and policy-makers. The criminal justice system relies on legitimacy and consent to an extent unlike other public services: public support is vital if the police and other criminal justice agencies are to function both effectively and in accordance with democratic norms. Yet we know little about the forms of social perception that stand prior to public confidence and police legitimacy. Drawing on data from the 2003/2004 British Crime Survey and the 2006/2007 London Metropolitan Police Safer Neighbourhoods Survey, this paper suggests that people think about their local police in ways less to do with the risk of victimization (instrumental concerns about personal safety) and more to do with judgments of social cohesion and moral consensus (expressive concerns about neighbourhood stability, cohesion and loss of collective authority). Across England and Wales the police may not primarily be seen as providers of a narrow sense of personal security, held responsible for crime and safety. Instead the police may stand as symbolic 'moral guardians' of social stability and order, held responsible for community values and informal social controls. We also present evidence that public confidence in the London Metropolitan Police Service expresses broader social anxieties about long-term social change. We finish our paper with some thoughts on a sociological analysis of the cultural place of policing: confidence (and perhaps ultimately the legitimacy of the police) might just be wrapped up in broader public concerns about social order and moral consensus.     

A generalization of Campbell and Kelly’s trade-off theorem

This article considers social choice theory without the Pareto principle. We revisit the trade-off theorem developed by Campbell and Kelly (Econometrica 61:1355–1365, 1993) and generalize their result. By introducing an alternative measure of decisive structure, a dominance relation, we show that if a social welfare function dominates another social welfare function, then the number of pairs of alternatives which social ranking is independently of individual preferences under the former is not more than that under the latter. Moreover, we offer two applications of our main result.     

The use of happiness research for public policy

Research on happiness tends to follow a “benevolent dictator” approach where politicians pursue people’s happiness. This paper takes an antithetic approach based on the insights of public choice theory. First, we inquire how the results of happiness research may be used to improve the choice of institutions. Second, we show that the policy approach matters for the choice of research questions and the kind of knowledge happiness research aims to provide. Third, we emphasize that there is no shortcut to an optimal policy maximizing some happiness indicator or social welfare function since governments have an incentive to manipulate this indicator.     

Reference functions and possibility theorems for cardinal social choice problems

 In this paper, we provide axiomatic foundations for social choice rules on a domain of convex and comprehensive social choice problems when agents have cardinal utility functions. We translate the axioms of three well known approaches in bargaining theory (Nash 1950; Kalai and Smorodinsky 1975; Kalai 1977) to the domain of social choice problems and provide an impossibility result for each. We then introduce the concept of a reference function which, for each social choice set, selects a point from which relative gains are measured. By restricting the invariance and comparison axioms so that they only apply to sets with the same reference point, we obtain characterizations of social choice rules that are natural analogues of the bargaining theory solutions. Received: 8 August 1994/Accepted: 12 February 1996     

Self-selective social choice functions

It is not uncommon that a society facing a choice problem has also to choose the choice rule itself. In such situations, when information about voters’ preferences is complete, the voters’ preferences on alternatives induce voters’ preferences over the set of available voting rules. Such a setting immediately gives rise to a natural question concerning consistency between these two levels of choice. If a choice rule employed to resolve the society’s original choice problem does not choose itself, when it is also used for choosing the choice rule, then this phenomenon can be regarded as inconsistency of this choice rule as it rejects itself according to its own rationale. Koray (Econometrica 68: 981–995, 2000) proved that the only neutral, unanimous universally self-selective social choice functions are the dictatorial ones. Here we introduce to our society a constitution, which rules out inefficient social choice rules. When inefficient social choice rules become unavailable for comparison, the property of self-selectivity becomes more interesting and we show that some non-trivial self-selective social choice functions do exist. Under certain assumptions on the constitution we describe all of them.     

Topological aggregation of preferences: the case of a continuum of agents

 This paper studies the topological approach to social choice theory initiated by G. Chichilnisky (1980), extending it to the case of a continuum of agents. The social choice rules are continuous anonymous maps defined on preference spaces which respect unanimity. We establish that a social choice rule exists for a continuum of agents if and only if the space of preferences is contractible. We provide also a topological characterization of such rules as generalized means or mathematical expectations of individual preferences. Received: 30 November 1994/Accepted: 22 April 1996