Simple plurality versus plurality runoff with privately informed voters

This paper compares two voting methods commonly used in presidential elections: simple plurality voting and plurality runoff. In a situation in which a group of voters have common interests but do not agree on which candidate to support due to private information, information aggregation requires them to split their support between their favorite candidates. However, if a group of voters split their support, they increase the probability that the winner of the election is not one of their favorite candidates. In a model with three candidates, due to this tension between information aggregation and the need for coordination, plurality runoff leads to higher expected utility for the majority than simple plurality voting if the information held by voters about the candidates is not very accurate. Received: 12 September 2000/Accepted: 8 November 2001     

The plurality majority converse under single peakedness

The plurality majority converse (PMC), the strongest possible instance of a plurality majority disagreement, is studied in the context of single peakedness. After sharpening some of the notions of unfolding theory we construct PMCs for the case where all voters' preference orders are single peaked on a common ordering of the political parties contesting in an election. A PMC then appears to result from a particular distribution of the voters' preference orders in which the political center has been dissolved towards the extremes. The possibility of a PMC in some of the elections in Weimar Germany is examined. Elections that avoid plurality majority disagreements by having voters choose one of a constrained set of preference orders over the contesting parties are discussed.     

Sophisticated voting and equilibrium refinements under plurality rule

In this paper we show in the context of voting games with plurality rule that the “perfect” equilibrium concept does not appear restrictive enough, since, independently of preferences, it can exclude at most the election of only one candidate. Furthermore, some examples show that there are “perfect” equilibria that are not “proper”. However, also some “proper” outcome is eliminated by sophisticated voting, while Mertens' stable set fully satisfies such criterium, for generic plurality games. Moreover, we highlight a weakness of the simple sophisticated voting principle. Finally, we find that, for some games, sophisticated voting (and strategic stability) does not elect the Condorcet winner, neither it respects Duverger's law, even with a large number of voters. Received: 16 March 1999/Accepted: 25 September 1999     

A law of large numbers for weighted plurality

Consider an election between $k$ candidates in which each voter votes randomly (but not necessarily independently) for a single candidate, and suppose that there is a single candidate that every voter prefers (in the sense that each voter is more likely to vote for this special candidate than any other candidate). Suppose we have a voting rule that takes all of the votes and produces a single outcome and suppose that each individual voter has little effect on the outcome of the voting rule. If the voting rule is a weighted plurality, then we show that with high probability, the preferred candidate will win the election. Conversely, we show that this statement fails for all other reasonable voting rules. This result is an extension of one by Häggström, Kalai and Mossel, who proved the above in the case $k=2$ .     

Shifting repertoires: understanding cultural plurality in policing

The police is one of the most prominent organizations in the frontline of public administration. In order to deal with high external expectations, the organization has been said to develop and nurture multiple police cultures. Applying Grid Group Cultural Theory, or GGCT, we address the following questions: what sets of values, beliefs and practices has the police organization developed to deal with high expectations stemming from their publics? How do cultural tensions play out in real-life practices of policing “under pressure”? We find that cultural patterns described in the general literature on policing can be plotted on the GGCT map. Zooming in on the case of policing in the Netherlands, cultural plurality appears to be not only prominent in the police organization as such, but can also be found in the form of continuous cultural “tap-dancing” – swift, flexible and improvisational shifting – at various levels of active policing.     

On asymptotic strategy-proofness of the plurality and the run-off rules

In this paper we prove that the plurality rule and the run-off procedure are asymptotically strategy-proof for any number of alternatives and that the proportion of profiles, at which a successful attempt to manipulate might take place, is in both cases bounded from above by , where n is the number of participating agents and K does not depend on n. We also prove that for the plurality rule the proportion of manipulable profiles is asymptotically bounded from below by , where k also does not depend on n. Received: 10 February 2000/Accepted: 19 October 2000     

The World Social Forum: the paradoxical quest for strength in plurality

ABSTRACT

In this reflexive essay, I explore how the present and the future of the World Social Forum are intimately related to the ability of its actors to acknowledge and actively address the inherent tensions of open spaces. The former must compose themselves articulating seemingly opposites: ideals shared within the World Social Forum vs. some practices not in accordance with its principles (enhanced in contexts of urgency); claimed horizontality vs. dynamic power relations; internal plurality vs. the need to act in unity to achieve systemic global change, amongst others. I will propose perspectives on how the strength of the WSF can be seen as its capacity to continue building radical hope for a positive shift of paradigm within progressive civil society: from divergences to resilient complementarities.     

A method for evaluating the behavior of power indices in weighted plurality games

In this paper, a systematic method to facilitate the comparison of a priori measures of power in an n-player r-candidate (n, r) weighted plurality game is proposed. This method, which exploits the notion of a structure of embedded winning coalitions (SEWC), enables the listing of all power profiles relevant to an (n, r) game under a given index and permits the computation of the probability of occurrence of each of these profiles. The vulnerability of an index to different paradoxes of power can also be systematically studied. For the purpose of illustration, we apply this method to the analysis of four well-known 2-candidate power indices namely the Shapley-Shubik index, the Banzhaf index, the Johnston index and the Deegan-Packel index. In each case, the set of power profiles and the likelihood of occurrence of each of these profiles are enumerated. The superadditivity property of these indices is also studied. Received: 20 October 1999/Accepted: 25 April 2001     

Policy convergence under approval and plurality voting: the role of policy commitment

Proponents of Approval Voting argue that this electoral rule leads to more centrist outcomes compared to Plurality Voting. This claim has been substantiated by scholarly work using spatial models of political competition. We revisit this issue in the context of a model of political competition in which (1) candidates are policy-motivated; (2) candidacy decisions are endogenous; and (3) candidates can credibly commit to implementing any policy. Under these assumptions we find the opposite to be true – Plurality Voting yields convergence to the median voter’s ideal policy but Approval Voting may not. We argue that this result is driven by the differential incentives for candidate entry under the two voting rules. Our results suggest that whether Approval Voting yields more centrist outcomes vis-á-vis Plurality Voting depends on the possibility of policy commitment on the part of the candidates. In an election held under PV each citizen is given one vote he can cast for one (and only one) candidate, and the candidate who gets the most votes wins the election.     

An extension of McGarvey’s theorem from the perspective of the plurality collective choice mechanism

In 1953, David McGarvey showed that if the number of voters is unrestricted, then the set of outputs obtained from majority rule is a very general class of binary relations. We will present an extension of McGarvey’s Theorem based on the plurality collective choice mechanism.     

Displeasure at plurality and fear of strangers? An empirical study among youth in Germany and the Netherlands

A comparison between the Netherlands and Germany concerning religious, cultural and ethnic plurality provides interesting insights. Germany has never defined itself as a multicultural society, as was historically the case in the Netherlands. The outcomes of the research are somewhat surprising. Dutch pupils – especially boys – are more negative about plurality than their German contemporaries are. Belonging to a church in Germany appears to be connected to a positive attitude to migrants, while in the Netherlands this is not important at all.     

Generic difference of expected vote share and probability of victory maximization in simple plurality elections with probabilistic voters

In this paper I examine single member, simple plurality elections with n ≥ 3 probabilistic voters and show that the maximization of expected vote share and maximization of probability of victory are “generically different” in a specific sense. More specifically, I first describe finite shyness (Anderson and Zame in Adv Theor Econ 1:1–62, 2000), a notion of genericity for infinite dimensional spaces. Using this notion, I show that, for any policy in the interior of the policy space and any candidate j, the set of n-dimensional profiles of twice continuously differentiable probabilistic voting functions for which simultaneously satisfies the first and second order conditions for maximization of j’s probability of victory and j’s expected vote share at is finitely shy with respect to the set of n-dimensional profiles of twice continuously differentiable probabilistic voting functions for which satisfies the first and second order conditions for maximization of j’s expected vote share.     

Soziologische Theorie, Methoden, Migrationssoziologie, Arbeitssoziologie, Wirtschaftssoziologie, Mitbestimmung, Umweltsoziologie

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Soziologische Theorie, Methoden, Migrationssoziologie, Arbeitssoziologie, Wirtschaftssoziologie, Mitbestimmung, Umweltsoziologie