Social Choice and Welfare

, Volume 29, Issue 4, pp 581–608 | Cite as

Welfarist evaluations of decision rules for boards of representatives

  • Claus Beisbart
  • Luc Bovens
Original Paper


We consider a decision board with representatives who vote on proposals on behalf of their constituencies. We look for decision rules that realize utilitarian and (welfarist) egalitarian ideals. We set up a simple model and obtain roughly the following results. If the interests of people from the same constituency are uncorrelated, then a weighted rule with square root weights does best in terms of both ideals. If there are perfect correlations, then the utilitarian ideal requires proportional weights, whereas the egalitarian ideal requires equal weights. We investigate correlations that are in between these extremes and provide analytic arguments to connect our results to Barberà and Jackson (J Polit Econ 114(2):317–339, 2006) and to Banzhaf voting power.


European Union Decision Rule Interest Group Expected Utility Vote Power 
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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  1. 1.Institute of Philosophy, Faculty 14University of DortmundDortmundGermany
  2. 2.Department of Philosophy, Logic and Scientific MethodLondon School of Economics and Political ScienceLondonUK

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