New Economics Papers
on Collective Decision-Making
Issue of 2005‒05‒23
four papers chosen by

  2. A Theory of Bicameralism By Giovanni Facchini; Cecilia Testa
  3. Judgment aggregation in general logics By Franz Dietrich
  4. The Effects of Constitutions on Coalition Governments in Parliamentary Democracies By Daniel Diermeier; Hulya Eraslan; Antonio Merlo

  1. By: Francesco De Sinopoli; Giovanna Iannantuoni
    Abstract: We study the strategic behavior of voters in a model of proportional representation, in which the policy space is multidimensional. Our main finding is that in large electorate, under some assumptions on voters' preferences, voters essentially vote, in any equilibrium, only for the extreme parties.
    Date: 2005–05
  2. By: Giovanni Facchini (University of Illinois, Department of Economics); Cecilia Testa (Department of Economics, Royal Holloway, University of London)
    Abstract: We model the role of a parliament’s structure in shaping the accountability of elected representatives. In a setting in which lawmakers interact with a lobby through a bargaining process and with voters by means of elections, we show that only a single legislative body who can make take it or leave it offers to the lobby can be held unambiguously accountable to voters. Whenever the pressure group enjoys some bargaining power, two chambers might instead provide better discipline, depending on the rules governing their interaction, and in particular the allocation of the decision powers among them. We show that bicameralism with restricted amendment rights provides the best incentives, while unrestricted amendment rights result in a status quo bias. Furthermore, by adding complexity of the legislative process, the presence of a second chamber might lead to an undesirable outcome, i.e. a decline in the legislator’s bargaining power vis `a vis the lobby and a reduction in his accountability. Arguments suggesting that bicameralism is a panacea against the abuse of power by elected legislators should therefore be taken with due caution.
    Keywords: Lobbying, bargaining, elections, accountability, bicameralism.
    JEL: D72 C78
    Date: 2005–03
  3. By: Franz Dietrich (University of Konstanz, Germany)
    Abstract: Within social choice theory, the new field of judgment aggregation aims to merge many individual sets of judgments on logically interconnected propositions into a single collective set of judgments on these propositions. Commonly, judgment aggregation is studied using standard propositional logic, with a limited expressive power and a problematic representation of conditional statements ('if P then Q') as material conditionals. In this methodological paper, I present a generalised model, in which most realistic decision problems can be represented. The model is not restricted to a particular logic but is open to several logics, including standard propositional logic, predicate calculi, modal logics and conditional logics. To illustrate the model, I prove an impossibility theorem, which generalises earlier results.
    Keywords: judgement aggregation, discursive dilemma, modelling methodology, formal logics, impossibility theorem
    JEL: D6 D7 H
    Date: 2005–05–18
  4. By: Daniel Diermeier (Kellogg School of Management,Northwestern University); Hulya Eraslan (Finance, Wharton School, University of Pennsylvania); Antonio Merlo (Department of Economics, University of Pennsylvania)
    Abstract: In this article we present an overview of our recent research on the effects of constitutions on coalition governments in parliamentary democracies. Our approach is based on the solution and estimation of a multilateral bargaining model which we use to investigate the consequences of constitutional features of parliamentary democracy for the formation and stability of coalition governments.
    Keywords: Political Stability, Coalition Governments, Constitutional Design
    JEL: D72 H19 C73
    Date: 2003–12–01

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