The Ordinal Equivalence of the Johnston Index and the Established Notions of Power

  • Sonali Roy
Part of the New Economic Windows book series (NEW)


(1978) proposed a number valued index that measures the power that individual voters have in a simple voting game. In this paper we show that the influence (or desirability) relation introduced by Isbell (1958) is a sub-preordering of the Johnston index for every simple voting game. Furthermore, the preorderings induced by the Johnston, Shapley-Shubik and Banzhaf-Coleman indices coincide if and only if the simple voting game is swap robust.


Simple Game Vote Power Winning Coalition Ordinal Equivalence Vote Situation 
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Copyright information

© Springer-Verlag Italia 2010

Authors and Affiliations

  • Sonali Roy
    • 1
  1. 1.Department of EconomicsIowa State UniversityAmesUSA

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