New Economics Papers
on Collective Decision-Making
Issue of 2006‒10‒14
eleven papers chosen by

  1. Beliefs and Voting Decisions: A Test of the Pivotal Voter Model By John Duffy; Margit Tavits
  2. Ideology and Existence of 50%-Majority Equilibria in Multidimensional Spatial Voting Models By M.Utku Unver; Herve Cres; M. Utku Unver
  3. On Measuring Influence in Non-Binary Voting Games By Vincent C H Chua; C H Ueng
  4. On Public Opinion Polls and Voters' Turnout By Esteban F. Klory; Eyal Winter
  5. Electoral Rules and Government Spending in Parliamentary Democracies By Torsten Persson; Gerard Roland; Guido Tabellini
  6. Weighted Approval Voting By Massó Jordi; Vorsatz Marc
  7. Arrovian juntas By Eisermann, Michael
  8. Judicial Independence, Elections and Minority Interests By Daniel Berkowitz; Chris Bonneau; Karen Clay
  9. Information Aggregation and Preference Heterogeneity in Committees By Elisabeth Schulte
  10. Single-peaked choice By Bossert Walter; Peters Hans
  11. The Control of Politicians in Divided Societies: The Politics of Fear By Gerard Padro i Miquel

  1. By: John Duffy; Margit Tavits
    Abstract: We report results from a laboratory experiment that provides the first direct test of the pivotal voter model. This model predicts that voters will rationally choose to vote only if their expected benefit from voting outweighs the cost. The expected benefit calculation involves the use of the voter’s subjective probability that s/he will be pivotal to the election outcome; this probability is typically unobservable. In one of our experimental treatments we elicit these subjective probabilities using a proper scoring rule that induces truthful revelation of beliefs. The cost of voting and the payoff to the election winner are known constants, so the subjective probabilities allow us to directly test the pivotal voter model. We find some support for the model: While a higher subjective probability of being pivotal does increase the likelihood that an individual chooses to vote, the decisiveness probability thresholds used by subjects are not as crisp as the theory would predict. We find some evidence that individuals learn over time to adjust their probabilities of being pivotal so that they are more consistent with the historical frequency of decisiveness, although such learning appears slow; many subjects\' assessments of their pivotalness remain substantially higher than is warranted by the electoral history.
    Date: 2006–09
  2. By: M.Utku Unver; Herve Cres; M. Utku Unver
    Date: 2005–01
  3. By: Vincent C H Chua (School of Economics and Social Sciences, Singapore Management University); C H Ueng (Victoria Junior College)
    Abstract: In this note, we demonstrate using two simple examples that generalization of the Banzhaf measure of voter influence to non-binary voting games that requires as starting position a voter’s membership in a winning coalition is likely to incompletely reflect the influence a voter has on the outcome of a game. Generalization of the Banzhaf measure that takes into consideration all possible pivot moves of a voter including those moves originating from a losing coalition will, on the other hand, result in a measure that is proportional to the Penrose measure only in the ternary case.
    Keywords: Penrose measure, Banzhaf index, ternary games, multicandidate weighted voting games
    JEL: C6 D7
    Date: 2004–12
  4. By: Esteban F. Klory; Eyal Winter
    Date: 2006–10–07
  5. By: Torsten Persson; Gerard Roland; Guido Tabellini
    Date: 2006–07–31
  6. By: Massó Jordi; Vorsatz Marc (METEOR)
    Abstract: To allow society to treat unequal alternatives distinctly we propose a natural extension of Approval Voting [7] by relaxing the assumption of neutrality. According to this extension, every alternative receives ex-ante a non-negative and finite weight. These weights may differ across alternatives. Given the voting decisions of every individual (individuals are allowed to vote for, or approve of, as many alternatives as they wish to), society elects all alternatives for which the product of total number of votes times exogenous weight is maximal. Our main result is an axiomatic characterization of this voting procedure.
    Keywords: microeconomics ;
    Date: 2006
  7. By: Eisermann, Michael
    Abstract: This article explicitly constructs and classifies all arrovian voting systems on three or more alternatives. If we demand orderings to be complete, we have, of course, Arrow's classical dictator theorem, and a closer look reveals the classification of all such voting systems as dictatorial hierarchies. If we leave the traditional realm of complete orderings, the picture changes. Here we consider the more general setting where alternatives may be incomparable, that is, we allow orderings that are reflexive and transitive but not necessarily complete. Instead of a dictator we exhibit a junta whose internal hierarchy or coalition structure can be surprisingly rich. We give an explicit description of all such voting systems, generalizing and unifying various previous results.
    Keywords: rank aggregation problem; Arrow's impossibility theorem; classification of arrovian voting systems; partial ordering; partially ordered set; poset; dictator; oligarchy; junta
    JEL: D71
    Date: 2006–08
  8. By: Daniel Berkowitz; Chris Bonneau; Karen Clay
    Date: 2006–01
  9. By: Elisabeth Schulte (Department of Economics, University of Mannheim)
    Abstract: This paper is concerned with the efficiency of information aggregation in a committee whose members have heterogeneous preferences over a binary decision variable. In a first stage, agents may exchange private (decision-relevant) information which is assumed to be verifiable. Then they reach a decision via majority voting. We study different information environments and identify conditions under which full information aggregation is possible. In particular, if preferences are common knowledge and each committee member is endowed with information full information aggregation is possible despite preference heterogeneity.
    Keywords: Information aggregation, committee decisions, preference heterogeneity
    JEL: D72 D78 D82
    Date: 2006–10
  10. By: Bossert Walter; Peters Hans (METEOR)
    Abstract: Single-peaked preferences have played an important role in the literature ever since they were used by Black (1948) to formulate a domain restriction that is sufficient for theexclusion of cycles according to the majority rule. In this paper, we approach single-peakedness from a choice-theoretic perspective. We show that the well-known axiom independence of irrelevant alternatives (a form of contraction consistency) and a weakcontinuity requirement characterize a class of single-peaked choice functions. Moreover, we examine the rationalizability and the rationalizability-representability of these choice functions.
    Keywords: microeconomics ;
    Date: 2006
  11. By: Gerard Padro i Miquel
    Abstract: Autocrats in many developing countries have extracted enormous personal rents from power. In addition, they have imposed inefficient policies including pervasive patronage spending. I present a model in which the presence of ethnic identities and the absence of institutionalized succession processes allow the ruler to elicit support from a sizeable share of the population despite large reductions in welfare. The fear of falling under an equally inefficient and venal ruler that favors another group is enough to discipline supporters. The model predicts extensive use of patronage, ethnic bias in taxation and spending patterns and unveils a new mechanism through which economic frictions translate into increased rent extraction by the leader. These predictions are consistent with the experiences of bad governance, ethnic bias, wasteful policies and kleptocracy in post-colonial Africa.
    JEL: D72 H2 O17 O55
    Date: 2006–10

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