Public Choice

, Volume 154, Issue 1–2, pp 75–94 | Cite as

Minimizing the threat of a positive majority deficit in two-tier voting systems with equipopulous units

  • Claus BeisbartEmail author
  • Luc Bovens


The mean majority deficit in a two-tier voting system is a function of the partition of the population. We derive a new square-root rule: For odd-numbered population sizes and equipopulous units the mean majority deficit is maximal when the member size of the units in the partition is close to the square root of the population size. Furthermore, within the partitions into roughly equipopulous units, partitions with small even numbers of units or small even-sized units yield high mean majority deficits. We discuss the implications for the winner-takes-all system in the US Electoral College.


Two-tier voting system Mean majority deficit Voting power Electoral College Sensitivity Majoritarianism 


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Institute for Philosophy and Political ScienceTU DortmundDortmundGermany
  2. 2.Department of Philosophy, Logic and Scientific MethodLondon School of Economics and Political ScienceLondonUK

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