Approval voting in subset elections

Summary. Approval voting is designed to be “insensitive to numbers” of voters, and likely to elect a Condorcet candidate. However, the result of an election among one group of candidates gives no information about the results of elections among any other groups, even if every voter follows the recommended utility-maximizing strategy, which places strong restrictions on the individual voter's subset ballots. Thus the addition of a single candidate could completely reverse the outcome of an election, or a Condorcet candidate could finish last. Received: November 5, 1998; revised version: November 30, 1998     

Strategy-proof and individually rational social choice functions for public good economies: A note

Summary. Serizawa [3] characterized the set of strategy-proof, individually rational, no exploitative, and non-bossy social choice functions in economies with pure public goods. He left an open question whether non-bossiness is necessary for his characterization. We will prove that non-bossiness is implied by the other three axioms in his characterization. Received: October 17, 1997; revised version: January 19, 1998     

Sequential voting with abstention

Dekel and Piccione [2000. Sequential voting procedures in symmetric binary elections. J. Polit. Economy 108, 34–55] have proven that information cascades do not necessarily affect the properties of information aggregation in sequential elections: under standard conditions, any symmetric equilibrium of a simultaneous voting mechanism is also an equilibrium of the correspondent sequential mechanism. We show that when voters can abstain, these results are sensitive to the introduction of an arbitrarily small cost of voting: the set of equilibria in the two mechanisms are generally disjoint; and the informative properties of the equilibrium sets can be ranked. If an appropriate q-rule is chosen, when the cost of voting is small the unique symmetric equilibrium of the simultaneous voting mechanism dominates all equilibria of the sequential mechanism.     

Non-manipulable domains for the Borda count

Summary. We characterize the preference domains on which the Borda count satisfies Arrows independence of irrelevant alternatives condition. Under a weak richness condition, these domains are obtained by fixing one preference ordering and including all its cyclic permutations (Condorcet cycles). We then ask on which domains the Borda count is non-manipulable. It turns out that it is non-manipulable on a broader class of domains when combined with appropriately chosen tie-breaking rules. On the other hand, we also prove that the rich domains on which the Borda count is non-manipulable for all possible tie-breaking rules are again the cyclic permutation domains.Received: 24 November 2003, Revised: 12 December 2004, JEL Classification Numbers: D71. Correspondence to: Clemens PuppeThe third author gratefully acknowledges the financial support from the Deutsche Forschungsgemeinschaft (DFG), Graduiertenkolleg 629 at the University of Bonn and from the Hungarian Scientific Research Fund (OTKA F 043496).     

The geometry of voting power: Weighted voting and hyper-ellipsoids

Suppose legislators represent districts of varying population, and their assembly's voting rule is intended to implement the principle of one person, one vote. How should legislators' voting weights appropriately reflect these population differences? An analysis requires an understanding of the relationship between voting weight and some measure of the influence that each legislator has over collective decisions. We provide three new characterizations of weighted voting that embody this relationship. Each is based on the intuition that winning coalitions should be close to one another. The locally minimal and tightly packed characterizations use a weighted Hamming metric. Ellipsoidal separability employs the Euclidean metric: a separating hyper-ellipsoid contains all winning coalitions, and omits losing ones. The ellipsoid's proportions, and the Hamming weights, reflect the ratio of voting weight to influence, measured as Penrose–Banzhaf voting power. In particular, the spherically separable rules are those for which voting powers can serve as voting weights.     

On the constancy of bribe-proof solutions

Summary. We consider the problem of choosing one point in a set of alternatives when monetary transfers are possible. In this context, Schummer (2000) shows that a social choice function must be a constant function if manipulation through bribes is ruled out. But he requires two kinds of domain-richness conditions. One is either smooth connectedness or the finiteness of the set of alternatives and the other is monotonical closedness. However, dispensing with the former condition, we alternatively prove the same result under a weaker condition than monotonical closedness. Received: April 11, 2000; revised version: February 25, 2002 RID="*" ID="*" This paper received the Osaka University Institute of Social and Economic Research Moriguchi Prize in January 2001. I am grateful to Prof. Ryoichi Nagahisa, Prof. Tatsuyoshi Saijo, Prof. Ken-ichi Shimomura, Prof. Ken Urai, and especially two anonymous referees for their useful and helpful comments and suggestions. I am a Research Fellow of the Japan Society for the Promotion of Science.     

Strategy-proof contract auctions and the role of ties

A contract auction establishes a contract between a center and one of the bidders. As contracts may describe many terms, preferences over contracts typically display indifferences. The Qualitative Vickrey Auction (QVA) selects the best contract for the winner that is at least as good for the center as any of the contracts offered by the non-winning players. When each bidder can always offer a contract with higher utility for the center at an arbitrarily small loss of her own utility, the QVA is the only mechanism that is individually rational, strategy-proof, selects stable outcomes, and is Pareto efficient. For general continuous utility functions, a variant of the QVA involving fixed tie-breaking is strategy-proof and also selects stable outcomes. However, there is no mechanism in this setting that in addition also selects Pareto efficient outcomes.     

A general impossibility result on strategy-proof social choice hyperfunctions

A social choice hyperfunction picks a non-empty set of alternatives at each admissible preference profile over sets of alternatives. We analyze the manipulability of social choice hyperfunctions. We identify a domain D^λ of lexicographic orderings which exhibits an impossibility of the Gibbard–Satterthwaite type. Moreover, this impossibility is inherited by all well-known superdomains of D^λ. As most of the standard extension axioms induce superdomains of D^λ while social choice correspondences are particular social choice hyperfunctions, we are able to generalize many impossibility results in the literature.     

Unsettling aspects of voting theory

Summary. Voting procedures are known to be plagued with a variety of difficulties such as strategic voting, or where a voter is rewarded with a better election outcome by not voting, or where a winning candidate can lose by receiving more support. Once we know that these problems can occur, the next objective should be to completely understand how, why, and where they arise. Namely, for each election procedure, the new goal is to determine when such problems can occur, all voter types who can cause these difficulties, and the actions they must take. This paper develops an easily used approach to handle all of these issues for standard voting methods. New intuitive explanations for these various oddities follow from this approach. Received: August 14, 2002 ; revised version: September 4, 2002 RID="*" ID="*"My thanks to Richard Barrett and, in particular, to Hannu Nurmi for corrections, several useful comments, and suggestions they made about earlier versions. Also, my thanks to a referee for calling some excellent references to my attention. An earlier draft was presented at the 2002 Public Choice Society meeting. This research was supported by an NSF grant.     

Random dictatorship domains

A domain of preference orderings is a random dictatorship domain if every strategy-proof random social choice function satisfying unanimity defined on the domain is a random dictatorship. Gibbard (1977) showed that the universal domain is a random dictatorship domain. We ask whether an arbitrary dictatorial domain is a random dictatorship domain and show that the answer is negative by constructing dictatorial domains that admit anonymous, unanimous, strategy-proof random social choice functions which are not random dictatorships. Our result applies to the constrained voting model. Lastly, we show that substantial strengthenings of linked domains (a class of dictatorial domains introduced in Aswal et al., 2003) are needed to restore random dictatorship and such strengthenings are “almost necessary”.     

Taxonomy: racism versus fiscal conservatism in voting on segregationist provisions in Alabama’s constitution

On Election Day 2004, a razor-thin majority of Alabama’s voters rejected a proposed amendment to remove overtly segregationist language from the state constitution. Opponents had contended that approval would have opened the legislative door to significantly higher taxes. We employ the results from two earlier special elections to analyze the outcome. In 2000, voters supported repealing a constitutional provision prohibiting interracial marriages. Three years later, Alabamians were asked to reveal their preferences with respect to additional taxation. The evidence suggests that opposition to higher taxes rather than bigotry was decisive in the rejection of Amendment 2 in 2004.

The empirical estimation of the cost-minimizing jury size and voting rule in civil trials

Since the early 1970s, the literature examining the court system has placed much emphasis on the importance of the jury size and voting rule when analyzing the jury decision-making process. In addition, researchers have also used deductive reasoning to theoretically determine the cost-minimizing jury size and voting rule with regards to Type I and Type II errors. In this paper, we take this analysis one step further by empirically estimating the cost-minimizing jury size and voting rule in civil jury trials.     

Political economy of eastern enlargement of the European Union: Budgetary costs and reforms in voting rules

Eastern European countries are likely to be major recipients of European Union (EU) funds after membership, which has created serious concern among incumbent members. The EU has devised reforms of budgetary rules to limit the funds that will flow to the East. Using a political economy model and drawing on the experience of previous enlargements, this paper argues that such pre-accession reforms will be ineffective because they can be reversed by a coalition of Eastern European countries after membership. The paper then estimates budgetary costs of eastern enlargement. A better way to resolve budgetary concerns is to reform voting rules rather than budgetary rules, before eastern enlargement.     

The structure of bias in peer voting systems: lessons from the Eurovision Song Contest

This paper assesses whether and how common characteristics of jury members or peer voters affect the outcomes of voting systems. In particular, we analyze to what extent these common features result in voting bias. We take as a case study the Eurovision Song Contest for which an extensive amount of historical data is available. In contrast to earlier studies we analyze the impact of common factors on the bias individually for each country, which is necessary to substantiate the publicly debated accusations of regional block voting by certain groups of countries. We establish strong evidence for voting bias in the song contest on the basis of geography, even after correction for culture, language, religion and ethnicity. However, these effects do generally not correspond to the usual accusations. We believe that our findings extend to all instances where groups of jury members or peer voters share certain common factors, which may cause voting bias. It is important to identify such structures explicitly, as it can help avoiding bias in the first place. The authors are grateful to Marieke van Dijk for excellent research assistance and to Laurens Swinkels, Ieva Pudane, Gijsbert van Lomwel, Jelena Stefanovic, and Bas van den Heuvel for useful comments. The usual disclaimer applies.     

Voting on voting with the feet: a cross-county analysis of the Tennessee popular referenda to secede from the union

We analyze a unique case of voting on voting with the feet, when Tennessee twice considered secession from the Union in 1861 by popular referenda. The initial votes to hold a convention, and to send disunion delegates to a convention, failed, but after the Confederate states adopted a new constitution and the bombing of Fort Sumter took place, a second set of votes to separate from the union, and to join the confederacy, passed. Regression results support the importance of both economic interests and political tendencies, along with regional differences, in explaining the variation in votes across counties. Class distinctions were not found to be significant.

Candidate stability and nonbinary social choice

Summary. The requirement that a voting procedure be immune to the strategic withdrawal of a candidate for election can be formalized in different ways. Dutta, Jackson, and Le Breton (Econometrica, 2001) have recently shown that two formalizations of this candidate stability property are 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 their impossibility theorems. Received: August 15, 2001; revised version: March 11, 2002 RID="*" ID="*" Parts of this article were previously circulated in somewhat different form in a working paper with the same title by the second author. We are grateful to Michel Le Breton and an anonymous referee for their comments. Correspondence to:J.A. Weymark