The purpose of this paper is to investigate the relationship between collective rationality and permissible collective choice rules using a unified approach inspired by Bossert and Suzumura (J Econ Theory 138:311–320, 2008). We consider collective choice rules satisfying four axioms: unrestricted domain, strong Pareto, anonymity, and neutrality. A number of new classes of collective choice rules as well as the Pareto and Pareto extension rules are characterized under various concepts of collective rationality: (...) acyclicity, transitivity, quasi-transitivity, semi-transitivity, and the interval order property. Further, new concepts of collective rationality, K-term acyclicity and K-term consistency, are proposed and the corresponding characterizations are provided. (shrink)

Suzumura consistency is a necessary and sufficient condition for the existence of a weak-order extension. This paper provides some remarks on collective choice rules that generate Suzumura consistent social preferences. We examine the properties of such collective choice rules by introducing a procedural condition on collective choice rules. As applications of the procedural condition, we first investigate the decisive structure of a Paretian collective choice rule, and then consider the assignment of individual (...) rights. In our analysis, the concept of semi-decisiveness works effectively. (shrink)

We examine the impact of Suzumura’s (Economica 43:381–390, 1976) consistency property when applied in the context of collective choice rules that are independent of irrelevant alternatives, neutral, and monotonic. An earlier contribution by Blau and Deb (Econometrica 45:871–879, 1977) establishes the existence of a vetoer if the collective relation is required to be complete and acyclical. The purpose of this paper is to explore the possibilities that result if completeness and acyclicity are dropped and Suzumura consistency is (...) imposed instead. A conceptually similar but logically independent version of the combined axiom that requires the collective decision mechanism to be independent, neutral, and monotonic is employed. In the case of a finite population, we obtain an alternative impossibility theorem if a collective choice rule is assumed to be non-degenerate and a modified no veto requirement is imposed instead of Blau and Deb’s (1977) condition. If the population is countably infinite, the impossibility can be avoided but it resurfaces if our new no veto property is extended to a coalitional variant. (shrink)

A new property of collective choice rules that we refer to as superset robustness is introduced, and we employ it in several characterization results. The axiom requires that if all individual preference orderings expand weakly (in the sense of set inclusion), then the corresponding social preference relation must also expand weakly. In other words, if a given profile is changed by adding instances of weak preference to some individual relations, then the social weak preference relation for the expanded (...) profile must contain the social weak preference relation for the original—that is, the social relation cannot contract in response to the addition of pairs to the individual relations. We begin by examining social welfare functions (that is, collective choice rules such that the resulting social preferences are orderings) and then move on to rules that generate transitive (but not necessarily complete) social rankings. The remaining results of the paper focus on Suzumura-consistent collective choice rules. In all of these cases, it turns out that the property of superset robustness is closely related to classes of agreement-based collective choice rules. These are rules such that the social relation is determined by collecting the pairs on whose relative rankings the members of the decisive sets agree. (shrink)

There is a collection of exogenously given socially feasible sets, and, for each one of them, each individual in a group chooses from an individually feasible set. The fact that the product of the individually feasible sets is larger than the socially feasible set notwithstanding, there arises no conflict between individual choices. Assuming that individual preferences are random, I characterize rationalizable collective choices.

To be pertinent to democratic practice, collective choice functions need not apply to all possible constellations of individual preference, but only to those that are humanly possible in an appropriate sense. The present paper develops a theory of humanly possible preference within the context of the mathematical theory of learning. The theory of preference is then exploited in an attempt to resolve Arrow's voting paradox through restriction of the domain of majoritarian choice functions.

A standard formulation of luck-egalitarianism says that ‘it is [in itself] bad – unjust and unfair – for some to be worse off than others [through no fault or choice of their own]’, where ‘fault or choice’ means substantive responsibility-generating fault or choice. This formulation is ambiguous: one ambiguity concerns the possible existence of a gap between what is true of each worse-off individual and what is true of the group of worse-off individuals, fault or choice-wise, (...) the other concerns the notion of fault. I show that certain ways of resolving these ambiguities lead to counterintuitive results; and that the most plausible way of resolving them leads to a theory of distributive justice in which responsibility plays a role significantly different from that in standard luck-egalitarian thinking. My main conclusion here is that luck-egalitarianism is best formulated as the view that it is [in itself] bad – unjust and unfair – for an individual to be worse off than others if, and only if, her being worse off does not fit the degree to which she is at fault in a not purely prudential sense. (shrink)

In “The Difference Principle Would Not Be Chosen behind the Veil of Ignorance,” Johan E. Gustafsson argues that the parties in the Original Position would not choose the Difference Principle to regulate their society’s basic structure. In reply to this internal critique, we provide two arguments. First, his choice models do not serve as a counterexample to the choice of the difference principle, as the models must assume that individual rationality scales to collective contexts in a way (...) that begs the question in favor of utilitarianism. Second, the choice models he develops are incompatible with the constraints of fairness that apply in the OP, which by design subordinates claims of rationality to claims of impartiality. When the OP is modeled correctly the difference principle is indeed entailed by the conditions of the OP. (shrink)

The key element structuring and sustaining social and economic relations is collective decision-making, i.e. the choices that groups (large or small) engage in to accommodate in the best way possib...

Building on case studies of Wikipedia and the Daily Kos, this essay argues that different kinds of rules shape relations between members of the majority and of the minority in these communities in important and consequential ways.

It is commonplace to suppose that the theory of individual rational choice is considerably less problematic than the theory of collective rational choice. In particular, it is often assumed by philosophers, economists, and other social scientists that an individual's choices among outcomes accurately reflect that individual's underlying preferences or values. Further, it is now well known that if an individual's choices among outcomes satisfy certain plausible axioms of rationality or consistency, that individual's choice-behavior can be interpreted (...) as maximizing expected utility on a utility scale that is unique up to a linear transformation. Hence, there is, in principle, an empirically respectable method of measuring individuals' values and a single unified schema for explaining their actions as value maximizing. (shrink)

The Quest to Understand Human Affairs presents fifty previously unpublished essays by Vincent Ostrom on the U.S. Government's environmental problems and resource governance and span the six decades of Ostrom's career in political science and public administration. Including everything from a 1947 essay on Western issues in national politics to ending with a 2004 manuscript on Constitutional foundations and federal institutional forms, these essays examine significant developments in administration, constitutional design, and the evolution of theory and practice in the field (...) of institutional analysis and development during the second half of the twentieth century and first decade of the new millennium. (shrink)

Sometimes citizens disagree about political matters, but a decision must be made. We have two theoretical frameworks for resolving political disagreement. The first is the framework of social choice. In it, our goal is to treat parties to the dispute fairly, and there is no sense in which some are right and the others wrong. The second framework is that of collective decision-making. Here, we do believe that preferences are truth apt, and our moral consideration is owed not (...) to those who disagree but to the community that stands to benefit or suffer from the decision. In this chapter, I describe and explore these two frameworks. I conclude two things. First, analysis of real-world disagreement suggests that collective decision-making is the right way to model politics. In most, possibly even all, political disagreement, all parties believe (if implicitly) that there is an objective standard of correctness. Second, this matter is connected to the concept of pluralism. If pluralism is true, then collective decision-making cannot be applied to some political disagreements. More surprisingly, pluralism may rule out the applicability of social choice theory as well. (shrink)

Designing a mechanism that provides a direct incentive for an individual to report her utility function over several alternatives is a difficult task. A framework for such mechanism design is the following: an individual (a decision maker) is faced with an optimization problem (e.g., maximization of expected utility), and a mechanism designer observes the decision maker’s action. The mechanism does reveal the individual’s utility truthfully if the mechanism designer, having observed the decision maker’s action, infers the decision maker’s utilities over (...) several alternatives. This paper studies an example of such a mechanism and discusses its application to the problem of optimal social choice. Under certain simplifying assumptions about individuals’ utility functions and about how voters choose their voting strategies, this mechanism selects the alternative that maximizes Harsanyi’s social utility function and is Pareto-efficient. (shrink)

The Quest to Understand Human Affairs presents fifty previously unpublished essays by Vincent Ostrom on the U.S. Government's environmental problems and resource governance and span the six decades of Ostrom's career in political science and public administration. Including everything from a 1947 essay on Western issues in national politics to ending with a 2004 manuscript on Constitutional foundations and federal institutional forms, these essays examine significant developments in administration, constitutional design, and the evolution of theory and practice in the field (...) of institutional analysis and development during the second half of the twentieth century and first decade of the new millennium. (shrink)

Taken collectively, consumer food choices have a major impact on animal lives, human lives, and the environment. But it is far from clear how to move from facts about the power of collective consumer demand to conclusions about what one ought to do as an individual consumer. In particular, even if a large-scale shift in demand away from a certain product (e.g., factory-farmed meat) would prevent grave harms or injustices, it typically does not seem that it will make a (...) difference whether one refrains from purchasing that product oneself. Most present-day food companies operate at too large a scale for a single purchase to make a difference to production decisions. If that is true, then it is not clear what point there is in refraining. This is “the problem of collective impact.” This chapter explores a range of proposals for how to solve this problem. (shrink)

Left freely to themselves, a group of rational individuals often fail to cooperate even when the product of social cooperation is beneficial to all. Hence, the author argues, a rule of collective decision making is clearly needed that specifies how social cooperation should be organised among contributing individuals. Suzumura gives a systematic presentation of the Arrovian impossibility theorems of social choice theory, so as to describe and enumerate the various factors that are responsible for the stability of the (...) voluntary association of free and rational individuals. Among other topics covered are an axiomatic characterisation of the concept of a rational choice, the simple majority decision rule and its extensions, the social choice implications of the concept of equity as nonenvy, the constrained majoritarian collective choice rules and the conflict between the Paretian ethics and the libertarian claims of individual rights. (shrink)

In order for traditional rational choice theory (RCT) to explain the production of collective action, it must be able to distinguish between two behaviorally identical possibilities: one, that all of the agents in a group are each performing behaviors in pursuit of a set of individual actions; and two, that all of those agents are performing those behaviors in pursuit of a collective action. I argue that RCT does not have the resources necessary to distinguish between these (...) two possibilities. RCT could distinguish between these possibilities if it were able to account for commitments. I argue that successful rational choice explanations of collective action appeal to commitments, and distinguish this way of explaining collective action from a general class of explanations called plural subject (or team reasoning) theories. (shrink)

This textbook provides a survey of the literature of social choice. It integrates the ethical aspects of the subject, with positive aspects of decision mechanisms that centre on the revelation of true preferences. The literature on the subject presently consists of a great many papers. This book draws them together in common notation and points out interpretations which are often missing in specialist papers. Applications in economics, electoral politics, and ethics are discussed. The book will be used by senior (...) undergraduate and graduate students of economics, political science and philosophy as a text book in the subject. (shrink)

Governments across the globe have squandered treasure and imprisoned millions of their own citizens by criminalising the use and sale of recreational drugs. But use of these drugs has remained relatively constant, and the primary victims are the users themselves. Meanwhile, antimicrobial drugs that once had the power to cure infections are losing their ability to do so, compromising the health of people around the world. The thesis of this essay is that policymakers should stop wasting resources trying to fight (...) an unwinnable and morally dubious war against recreational drug users, and start shifting their attention to the serious threat posed by our collective misuse of antibiotics. (shrink)

Can teams and other collectivities have preferences of their own, preferences that are not in some way reducible to the personal preferences of their members? In short, are collective preferences possible? In everyday life people speak easily of what we prefer, where what is at issue seems to be a collective preference. This is suggested by the acceptability of such remarks as ‘My ideal walk would be . . . along rougher and less well-marked paths than we prefer (...) as a family’. One can imagine, indeed, that each member of a given family prefers something other than what the family prefers. What, then, do the collective preferences of everyday understanding amount to? (shrink)

In order for traditional rational choice theory to explain the production of collective action, it must be able to distinguish between two behaviorally identical possibilities: one, that all of the agents in a group are each performing behaviors in pursuit of a set of individual actions; and two, that all of those agents are performing those behaviors in pursuit of a collective action. I argue that RCT does not have the resources necessary to distinguish between these two (...) possibilities. RCT could distinguish between these possibilities if it were able to account for commitments. I argue that successful rational choice explanations of collective action appeal to commitments, and distinguish this way of explaining collective action from a general class of explanations called plural subject theories. (shrink)

Condorcet's jury theorem shows that when the members of a group have noisy but independent information about what is best for the group as a whole, majority decisions tend to outperform dictatorial ones. When voting is supplemented by communication, however, the resulting interdependencies between decision makers can strengthen or undermine this effect: they can facilitate information pooling, but also amplify errors. We consider an intriguing non-human case of independent information pooling combined with communication: the case of nest-site choice by (...) honeybee (Apis mellifera) swarms. It is empirically well documented that when there are different nest sites that vary in quality, the bees usually choose the best one. We develop a new agent-based model of the bees' decision process and show that its remarkable reliability stems from a particular interplay of independence and interdependence between the bees. (shrink)

We argue that conceptual analyses of collective action should be informed by game-theoretic analyses of collective action. In particular, we argue that Ariel Rubenstein’s so-called ‘Electronic Mail Game’ provides a useful model of collective action, and of the formation of collective intentions.

Condorcet's classic jury theorem shows that when the members of a group have noisy but independent information about what is best for the group as a whole, majority decisions tend to outperform dictatorial ones. When voting is supplemented by communication, however, the resulting interdependencies between decision-makers can strengthen or undermine this effect: they can facilitate information pooling, but also amplify errors. We consider an intriguing non-human case of independent information pooling combined with communication: the case of nest-site choice by (...) honey bee swarms. It is empirically well-documented that when there are different nest sites that vary in quality, the bees usually choose the best one. We develop a new agent-based model of the bees’ decision process and show that its remarkable reliability stems from a particular interplay of independence and interdependence between the bees. (shrink)

Foundation models such as GPT-4 are fine-tuned to avoid unsafe or otherwise problematic behavior, so that, for example, they refuse to comply with requests for help with committing crimes or with producing racist text. One approach to fine-tuning, called reinforcement learning from human feedback, learns from humans' expressed preferences over multiple outputs. Another approach is constitutional AI, in which the input from humans is a list of high-level principles. But how do we deal with potentially diverging input from humans? How (...) can we aggregate the input into consistent data about "collective" preferences or otherwise use it to make collective choices about model behavior? In this paper, we argue that the field of social choice is well positioned to address these questions, and we discuss ways forward for this agenda, drawing on discussions in a recent workshop on Social Choice for AI Ethics and Safety held in Berkeley, CA, USA in December 2023. (shrink)

Social choice theory is the study of collective decision processes and procedures. It is not a single theory, but a cluster of models and results concerning the aggregation of individual inputs (e.g., votes, preferences, judgments, welfare) into collective outputs (e.g., collective decisions, preferences, judgments, welfare). Central questions are: How can a group of individuals choose a winning outcome (e.g., policy, electoral candidate) from a given set of options? What are the properties of different voting systems? When (...) is a voting system democratic? How can a collective (e.g., electorate, legislature, collegial court, expert panel, or committee) arrive at coherent collective preferences or judgments on some issues, on the basis of its members' individual preferences or judgments? How can we rank different social alternatives in an order of social welfare? Social choice theorists study these questions not just by looking at examples, but by developing general models and proving theorems. (shrink)

Sometimes a series of choices do not serve one's concerns well even though each choice in the series seems perfectly well suited to serving one's concerns. In such cases, one has a dynamic choice problem. Otherwise put, one has a problem related to the fact that one's choices are spread out over time. This survey reviews some of the challenging choice situations and problematic preference structures that can prompt dynamic choice problems. It also reviews some proposed (...) solutions, and explains how some familiar but potentially puzzling phenomena — including, for example, self-destructive addictive behavior and dangerous environmental destruction — have been illuminated by dynamic choice theory. (shrink)

This article provides a systematic analysis of social choice theory without the Pareto principle, by revisiting the method of Murakami Yasusuke. This article consists of two parts. The first part investigates the relationship between rationality of social preference and the axioms that make a collective choice rule either Paretian or anti-Paretian. In the second part, the results in the first part are applied to obtain impossibility results under various rationality requirements of social preference, such as S-consistency, quasi-transitivity, (...) semi-transitivity, the interval-order property, and acyclicity. (shrink)

Kurt Godel was the most outstanding logician of the twentieth century, famous for his work on the completeness of logic, the incompleteness of number theory, and the consistency of the axiom of choice and the continuum hypothesis. He is also noted for his work on constructivity, the decision problem, and the foundations of computation theory, as well as for the strong individuality of his writings on the philosophy of mathematics. Less well-known is his discovery of unusual cosmological models for (...) Einstein's equations, permitting "time-travel" into the past. This second volume of a comprehensive edition of Godel's works collects together all his publications from 1938 to 1974. Together with Volume I (Publications 1929-1936), it makes available for the first time in a single source all of his previously published work. Continuing the format established in the earlier volume, the present text includes introductory notes that provide extensive explanatory and historical commentary on each of the papers, a facing English translation of the one German original, and a complete bibliography. Succeeding volumes are to contain unpublished manuscripts, lectures, correspondence, and extracts from the notebooks. Collected Works is designed to be accessible and useful to as wide an audience as possible without sacrificing scientific or historical accuracy. The only complete edition available in English, it will be an essential part of the working library of professionals and students in logic, mathematics, philosophy, history of science, and computer science. These volumes will also interest scientists and all others who wish to be acquainted with one of the great minds of the twentieth century. (shrink)

This book presents the definitive exposition of 'prospect theory', a compelling alternative to the classical utility theory of choice. Building on the 1982 volume, Judgement Under Uncertainty, this book brings together seminal papers on prospect theory from economists, decision theorists, and psychologists, including the work of the late Amos Tversky, whose contributions are collected here for the first time. While remaining within a rational choice framework, prospect theory delivers more accurate, empirically verified predictions in key test cases, as (...) well as helping to explain many complex, real-world puzzles. In this volume, it is brought to bear on phenomena as diverse as the principles of legal compensation, the equity premium puzzle in financial markets, and the number of hours that New York cab drivers choose to drive on rainy days. Theoretically elegant and empirically robust, this volume shows how prospect theory has matured into a new science of decision making. (shrink)

Currently, many consumers have expressed strong opinions about food production process, its distribution, and guaranteeing models. Consumers’ concerns about ecological and social sustainability issues can have significant impacts on both food demand and food policies. The choice of approach to an asset or service could determine the orientation of the markets; therefore, it is particularly important to pay attention to novel, collective, social movements which are practicing alternatives to the mainstream models of production, distribution, and consumption. Farmers markets, (...) solidarity-based purchasing groups, box scheme, shopping groups, ‘pick your own’, social shopping, are all examples of sustainable consumption patterns involving thousands of people seeking quality and ethical products and services at the best price. While a variety of definitions of the concept of ethical consumption have been suggested, throughout this paper it will refer to the participation of consumers in, and their orientation toward, political discourses on sustainable and fair agro-food production. Ethical consumption attitude has been analysed in the framework of political consumerism theory by administering six focus groups among Italian participants of a specific form of collective action, namely the solidarity-based purchasing group. Findings provide insights that represent a fruitful starting point for deepening the analysis of ethical consumers’ behaviour at a broader level in order to sustain and spread eco-socially production practices and ethical consumption behaviour. (shrink)

The two most influential traditions of contemporary theorizing about democracy, social choice theory and deliberative democracy, are generally thought to be at loggerheads, in that the former demonstrates the impossibility, instability or meaninglessness of the rational collective outcomes sought by the latter. We argue that the two traditions can be reconciled. After expounding the central Arrow and Gibbard-Satterthwaite impossibility results, we reassess their implications, identifying the conditions under which meaningful democratic decision making is possible. We argue that deliberation (...) can promote these conditions, and hence that social choice theory suggests not that democratic decision making is impossible, but rather that democracy must have a deliberative aspect. (shrink)

Dung’s argumentation frameworks have been applied for over twenty years to the analysis of argument justification. This representation focuses on arguments and the attacks among them, abstracting away from other features like the internal structure of arguments, the nature of utterers, the specifics of the attack relation, etc. The model is highly attractive because it reduces most of the complexities involved in argumentation processes. It can be applied to different settings, like the argument evaluation of an individual agent or the (...) case of dialectic disputes between two agents (pro and con), or even in multi-agent collective argumentation. The latter case involves agents with possibly different arguments and/or opinions on how to evaluate them, leading to the possibility of considering multiple sets of arguments and attack relations. Two basic questions can be asked here, namely ‘what to aggregate’ and ‘how to aggregate’. The former concerns what kinds of entities do the agents intend to choose (arguments, attacks, assessments, etc.), while the second one focuses on which aggregation mechanisms yield rational choices (voting on arguments, merging procedures to obtain a common argumentation framework, deliberation processes, etc.). In particular, the question about the rationality of a collective argument choice relates this topic to Social Choice and Judgment Aggregation theories, while its associated strategic issues relate it to Game Theory. The research efforts on the disparate problems elicited by collective argumentation have generated a considerable corpus of literature that deserves an orderly evaluation. This survey is intended as a contribution to that end. (shrink)

In this paper, it is about the axiomatic basis of rational choice theory - the theory that is behind making rational choice and decisions. To make rational choices, we would require thinking rationally and understanding the reason and logic behind what makes a choice rational, and how we need to choose rationally. Decisions are made under various circumstances, i.e., under risk, and often under compulsion. In social choice theory, decisions are made by different types of decision (...) making entities, i.e., committees, groups, individuals and collective judgments by various types of organizations, etc. This paper highlights these issues and addresses the fundamental tenets of making rational choices by examining and following the previous workings of experts on this field. As such, it introduces a novel concept and the idea of Social Choice Rationality in choosing what’s rational. (shrink)

Is it rational to be moral? How do rationality and morality fit together with being human? These questions are at the heart of David Schmidtz's exploration of the connections between rationality and morality. This inquiry leads into both metaethics and rational choice theory, as Schmidtz develops conceptions of what it is to be moral and what it is to be rational. He defends a fairly expansive conception of rational choice, considering how ends as well as means can be (...) rationally chosen and explaining the role of self-imposed constraints in a rational life plan. His moral theory is dualistic, ranging over social structure as well as personal conduct and building both individual and collective rationality into its rules of recognition for morals. To the "why be moral" question, Schmidtz responds that being moral is rational, but he does not assume we have reasons to be rational. Instead, Schmidtz argues that being moral is rational in a particular way and that beings like us in situations like ours have reasons to be rational in just that way. This approach allows him to identify decisive reasons to be moral; at the same time, it explains why immorality is as prevalent as it is. This book thus offers a set of interesting and realistic conclusions about how morality fits into the lives of humanly rational agents operating in an institutional context like our own. (shrink)

We establish a correspondence between the rationalizability of choice studied in the revealed preference literature and the notion of minimal belief revision captured by the AGM postulates. A choice frame consists of a set of alternatives , a collection E of subsets of (representing possible choice sets) and a function f : E ! 2 (representing choices made). A choice frame is rationalizable if there exists a total pre-order R on..