This introductory text explores the theory of social choice. Written as a primer suitable for advanced undergraduates and graduates, this text will act as an important starting point for students grappling with the complexities of social choice theory. Rigorous yet accessible, this primer avoids the use of technical language and provides an up-to-date discussion of this rapidly developing field. This is the first in a series of texts published in association with the LSE.

Kuhn claimed that several algorithms can be defended to select the best theory based on epistemic values such as simplicity, accuracy, and fruitfulness. In a recent paper, Okasha :83–115, 2011) argued that no theory choice algorithm exists which satisfies a set of intuitively compelling conditions that Arrow had proposed for a consistent aggregation of individual preference orderings. In this paper, we put forward a solution to avoid this impossibility result. Based on previous work by Gaertner and Xu, we suggest to (...) view the theory choice problem in a cardinal context and to use a general scoring function defined over a set of qualitative verdicts for every epistemic value. This aggregation method yields a complete and transitive ranking and the rule satisfies all Arrovian conditions appropriately reformulated within a cardinal setting. We also propose methods that capture the aggregation across different scientists. (shrink)

Wulf Gaertner provides a comprehensive account of an important and complex issue within social choice theory: how to establish a social welfare function while restricting the spectrum of individual preferences in a sensible way. Gaertner's starting point is K. J. Arrow's famous 'Impossibility Theorem', which showed that no welfare function could exist if an unrestricted domain of preferences is to be satisfied together with some other appealing conditions. A number of leading economists have tried to provide avenues out of this (...) 'impossibility' by restricting the variety of preferences: here, Gaertner provides a clear and detailed account, using standardized mathematical notation, of well over forty theorems associated with domain conditions. Domain Conditions in Social Choice Theory will be an essential addition to the library of social choice theory for scholars and their advanced graduate students. (shrink)

This introductory text explores the theory of social choice. This text is an important starting point for students grappling with the complexities of social choice theory. Rigorous yet accessible, with new chapter exercises, it avoids the use of technical language and provides an up-to-date discussion of this rapidly developing field.

This paper studies a ranking rule of the following type axiomatically: each voter places k candidates into n categories with ranks from n to 1 attached to these categories, the candidate(s) with the highest aggregate score is (are) the winner(s). We show that it is characterized by a monotonicity condition and a multi-stage cancellation property.

This paper examines the exercise of individual or group rights within the game form approach. It focuses in particular on what it means for a strategy or action to be feasible and admissible. Admissibility is best discussed in relation to two basic distinctions among rights, passive and active rights on the one hand and negative and positive rights on the other. It is argued that while there are quite a few cases in which the outcomes of mutual rights exercising are (...) to the fore, there are many situations where the uninhibited exercise of individual or group rights and not particular outcomes are what society is primarily interested in. (shrink)

ZusammenfassungZur Verringerung der Knappheit an Organen wird die Einführung eines Marktes für menschliche Organe vorgeschlagen. Personen, die ihre Organe verkaufen, und Personen, die ihre Organe lebend spenden, sind medizinisch den gleichen Gefahren ausgesetzt. Der Verkaufserlös bietet für den Abgebenden eine Einkommenssteigerung, die vielfältig genutzt werden kann. Die auf Schwarzmärkten beobachteten negativen Effekte sollen durch eine strikte Überwachung und Regulierung verhindert werden. Der Markt für Organe kann von zwei getrennten Ankaufsorganisationen geprägt werden. Eine Organisation zahlt die Weiterverkaufserlöse der Organe direkt an (...) die Geber aus, eine andere Organisation investiert sie stattdessen in wohltätige Zwecke und gibt so den Gebern die Möglichkeit, ihr Organ aus rein altruistischen Motiven zu spenden. Die Finanzierung des Systems soll durch das öffentliche Gesundheitssystem bzw. die privaten Krankenversicherungen erfolgen. (shrink)

There are public projects which many people welcome because they are expected to be beneficial for society at large. On the other hand, however, these projects may generate larger negative externalities for certain parts of society. One example is the erection of a nuclear power-plant, a measure that is widely considered to render a country’s energy provision less dependent on supply from outside. On the other hand, it possibly causes a feeling of insecurity among people who live in the vicinity (...) of such a power station, and can furthermore have negative economic consequences in so far as the price of land and of houses may decline in this area. How should decisions on public projects with larger negative externalities be taken? Assuming that the benefits for all those who are directly or indirectly affected by such a project are roughly the same, a cost-sharing or burden-sharing method is proposed that focuses on a weighted difference between the economic performance of a particular region and the average performance of all regions concerned. The weight is to be determined by an impartial observer. (shrink)

Zur Verringerung der Knappheit an Organen wird die Einführung eines Marktes für menschliche Organe vorgeschlagen. Personen, die ihre Organe verkaufen, und Personen, die ihre Organe lebend spenden, sind medizinisch den gleichen Gefahren ausgesetzt. Der Verkaufserlös bietet für den Abgebenden eine Einkommenssteigerung, die vielfältig genutzt werden kann. Die auf Schwarzmärkten beobachteten negativen Effekte sollen durch eine strikte Überwachung und Regulierung verhindert werden. Der Markt für Organe kann von zwei getrennten Ankaufsorganisationen geprägt werden. Eine Organisation zahlt die Weiterverkaufserlöse der Organe direkt an (...) die Geber aus, eine andere Organisation investiert sie stattdessen in wohltätige Zwecke und gibt so den Gebern die Möglichkeit, ihr Organ aus rein altruistischen Motiven zu spenden. Die Finanzierung des Systems soll durch das öffentliche Gesundheitssystem bzw. die privaten Krankenversicherungen erfolgen. (shrink)

If an agent is unsure about which moral theory or principle should guide her action in a decision situation, she faces moral uncertainty. In recent years, various strategies have been explored to deal with this type of uncertainty. In this paper, we briefly mention two strategies from the literature that make use of credence distributions over moral theories, namely “my favourite theory” and “maximizing expected choice-worthiness”. As an alternative, we propose a two-step procedure which uses the concept of aggregation over (...) structural properties. It is standard in the theory of collective choice and has recently been applied to the Kuhnian problem of theory choice as well. The idea is to explore how a morally-motivated rational agent may assess different moral theories on the basis of fundamental properties. These properties are ranked on a common scale of qualitative verdicts. This method enables an outside observer to make comparisons across competing moral theories and then conclude to what degree these theories fulfil a set of postulated properties. By doing so, we try to render the reasons more transparent that lie behind different types of credence ascriptions. (shrink)

This article contributes to the literature on the evaluation of sets of opportunities. The starting point is Lancaster's characteristics approach. However, instead of assuming the existence of a canonical utility function, a reference point or reference level is postulated from which an agent evaluates set expansions in appropriate directions. One of the major tools for this exercise is the notion of directed cones. Desirability of characteristics is restricted to the interior of these cones. Satiation and non-monotonic evaluation is considered as (...) well. An axiomatic characterization for various cases is provided. (shrink)

This paper discusses justice-constrained libertarian claims that were proposed as a way to circumvent the impossibility of the Paretian liberal. Since most of the results are negative in character, we suggest an alternative route: A requirement on the structure of individual orderings should be combined with the idea that under particular circumstances individual decisiveness should be controlled by higher-order principles.

Arrow’s impossibility result not only had a profound influence on welfare economics, but was, as this paper shows, also widely discussed in philosophy of science and in the engineering design literature.

In 1981, the property of self-supporting preferences was shown to be a sufficient condition to circumvent Sen’s famous impossibility result on Paretian liberalism. A similar condition was proposed by Dougherty and Edward in a very recent issue of this journal. The present comment sheds light on the logical connection between these two findings.

This article uses Lancaster's characteristics approach to rank sets of alternative combinations of commodity characteristics. It is assumed that there exists a reference point or reference level from which the individual evaluates set expansions in appropriate directions. We provide an axiomatic characterization for such a case.

This paper discusses evaluations of distributive justice in two different situations. Focal point is the so-called equity axiom which lies at the heart of Rawls’ second principle of justice, the maximin rule. Our investigation which was run at a German university spans over a period of fifteen years. It seems to us that consideration for the worst-off (group) in society has become considerably weaker over the years. This and related observations are tested by using a probit model including several demographic (...) characteristics of the probands. The supposed time trend proves to be statistically robust. Several reasons for this observation are given. Obviously, depending on the underlying context, evaluations are to some degree influenced by current topics, including the ongoing discussion about the German educational system as well as about recent economic problems. We also briefly refer to findings that we obtained in the Baltics and in Israel. (shrink)

In an article from 1973, Rittel and Webber distinguished between “tame” or “benign” problems on the one hand and “wicked” problems on the other. The authors argued that wicked problems occur in nearly all public policy issues. Since different groups adhere to different value-sets, solutions can only be expressed as better or worse. By no means can they be viewed as definitive or objective. In this paper we shall consider, from this very angle, the theory of social choice which is (...) about the aggregation of individual preferences with the aim to derive a consistent social preference. We shall show that collective choice offers wicked problems of various types which differ in their degree of severity. We shall hereby concentrate on welfare functions and voting schemes of different kinds and shall discuss these in the light of various criteria such as Arrow’s independence condition, Condorcet consistency, monotonicity, manipulability, and other properties. (shrink)

We examine individuals’ distributional orderings in a number of contexts. This is done by using a questionnaire-experiment that is presented to respondents in any one of seven “flavors” or interpretations of the basic distributional problem. The flavors include inequality, risk, social welfare and justice.