Consensus in organizations:Hunting for the social choice conundrum in APA elections

According to the axiomatic literature on consensus methods, the best collective choice by one method of preference aggregation can easily be the worst by another. Are award committees, electorates, managers, online retailers, and web-based recommender systems stuck with an impossibility of rational preference aggregation? We investigate this social choice conundrum for seven social choice methods: Condorcet, Borda, Plurality, Antiplurality, the Single Transferable Vote, Coombs, and Plurality Runoff. We rely on Monte Carlo simulations for theoretical results and on twelve ballot datasets from American Psychological Association (APA) presidential elections for empirical results. Each of these elections provides partial rankings of five candidates from about 13,000 to about 20,000 voters. APA preferences are neither domain-restricted nor generated by an Impartial Culture. We find virtually no trace of a Condorcet paradox. In direct contrast with the classical social choice conundrum, competing consensus methods agree remarkably well, especially on the overall best and worst options. The agreement is also robust under perturbations of the preference prole via resampling, even in relatively small pseudosamples. We also explore prescriptive implications of our findings.

Candidate Stability and Nonbinary Social Choice

A desirable property of a voting procedure is that it be immune to the strategic withdrawal of a candidate for election. Dutta, Jackson, and Le Breton (Econometrica, 2001) have established a number of theorems that demonstrate that this condition is incompatible with some other desirable properties of voting procedures. This article shows that Grether and Plott's nonbinary generalization of Arrow's Theorem can be used to provide simple proofs of two of these impossibility theorems.

Social Choice: Recent Developments

In the past quarter century, there has been a dramatic shift of focus in social choice theory, with structured sets of alternatives and restricted domains of the sort encountered in economic problems coming to the fore. This article provides an overview of some of the recent contributions to four topics in normative social choice theory in which economic modelling has played a prominent role: Arrovian social choice theory on economic domains, variable-population social choice, strategy-proof social choice, and axiomatic models of resource allocation.

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 situation voters’ preferences on alternatives induce preferences over the 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 in 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 (2000) proved that the only neutral, unanimous universally self-selective social choice functions are the dictatorial ones. Here we in troduce 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 weaker 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.

Multi-Profile Intergenerational Social Choice

Ferejohn and Page transplanted a stationarity axiom from Koopmans’ theory of impatience into Arrow’s social choice theory with an infinite horizon and showed that the Arrow axioms and stationarity lead to a dictatorship by the first generation. We prove that the negative implications of their stationarity axiom are more far-reaching: there is no Arrow social welfare function satisfying their stationarity axiom. We propose a more suitable stationarity axiom, and show that an Arrow social welfare function satisfies this modified version if and only if it is a lexicographic dictatorship where the generations are taken into consideration in chronological order.

Extensive Social Choice and the Measurement of Group Fitness in Biological Hierarchies

Extensive social choice theory is used to study the problem of measuring group fitness in a two-level biological hierarchy. Both fixed and variable group size are considered. Axioms are identified that imply that the group measure satisfies a form of consequentialism in which group fitness only depends on the viabilities and fecundities of the individuals at the lower level in the hierarchy. This kind of consequentialism can take account of the group fitness advantages of germ-soma specialization, which is not possible with an alternative social choice framework proposed by Okasha, but which is an essential feature of the index of group fitness for a multicellular organism introduced by Michod, Viossat, Solari, Hurand, and Nedelcu to analyze the unicellular-multicellular evolutionary transition. The new framework is also used to analyze the fitness decoupling between levels that takes place during an evolutionary transition.

Multi-Profile Intertemporal Social Choice

We provide a brief survey of some literature on intertemporal social choice theory in a multi-profile setting. As is well-known, Arrow’s impossibility result hinges on the assumption that the population is finite. For infinite populations, there exist nondictatorial social welfare functions satisfying Arrow’s axioms and they can be described by their corresponding collections of decisive coalitions. We review contributions that explore whether this possibility in the infinite-population context allows for a richer class of social welfare functions in an intergenerational model. Different notions of stationarity formulated for individual and for social preferences are examined. Journal of Economic Literature Classification No.: D71.

Population Ethics, Social Choice Theory, and Two problems in the Measurement of Economic Poverty

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Measuring social welfare: application of social choice theory

This paper questions conventional approaches to measuring social welfare through gross domestic product (GDP). This paper is divided into two parts. The first part adopts a systems approach to development and incorporates this into the theory of social choice. The second part operationalises this approach through the development of a cost-benefit adjusted gross domestic product (CBAGDP) social welfare function, which overcomes certain limitations of this traditional measure of development. The CBAGDP is then used to estimate welfare in Thailand. This approach is justified because of its normative values and its plausible results.

Measuring human well-being in Thailand : a normative social choice approach

Numerous methods exist within the literature to measure human well-being. A limitation of some approaches however is that they fail to explicitly consider society's views, choices and preferences on how human well-being should be defined. It is possible though to explicitly incorporate society's value judgements in defining and measuring human well-being through normative social choice theory. Normative social choice theory reflects the views, opinions and perspectives of societies of differing economic and social circumstances so that measures of human well-being retain their relevance for public policy makers in those countries. This paper reviews two indicators based on this theory for Thailand over the 25 year period, 1975-1999. The first indicator focuses on certain hierarchical needs and the second is a measure of adjusted national income. It is concluded that both measures provide important insights.

The welfare economics of measuring sustainability: a new approach based on social choice theory and systems analysis

This paper presents a new measure of sustainability within a welfare economics framework. Gross domestic product (GDP) can be used as an indicator of sustainability if the GDP estimates are undertaken within a cost-benefit analysis framework based on social choice perspectives. Sustainability is dependent on a healthy and functioning socio-economic and environmental (SEE) system. Economic development can damage the SEE system through resource degradation, over-harvesting and pollution. This paper addresses the tensions between economic development and sustainability by undertaking a number of SEE-based adjustments to GDP based on social choice perspectives in order to measure sustainability. These adjustments include the environmental and social costs caused by economic development such as water pollution, the depletion of non-renewable resources, and deforestation. Thailand is used as a case study for a 25 year period (1975-1999). The results show a divergence in terms of GDP per capita and the SEE-adjusted GDP per capita figure. The paper concludes that, with increasing environmental and social costs of economic development, pursuing such extreme high growth objectives without due environmental and social considerations can threaten present social welfare and future sustainability. Copyright © 2005 John Wiley & Sons, Ltd and ERP Environment.