Theory and Decision

, Volume 71, Issue 4, pp 439–459 | Cite as

Optimal jury design for homogeneous juries with correlated votes

  • Serguei KaniovskiEmail author
  • Alexander Zaigraev


In a homogeneous jury, in which each vote is correct with the same probability, and each pair of votes correlates with the same correlation coefficient, there exists a correlation-robust voting quota, such that the probability of a correct verdict is independent of the correlation coefficient. For positive correlation, an increase in the correlation coefficient decreases the probability of a correct verdict for any voting rule below the correlation-robust quota, and increases that probability for any above the correlation-robust quota. The jury may be less competent under the correlation-robust rule than under simple majority rule and less competent under simple majority rule than a single juror alone. The jury is always less competent than a single juror under unanimity rule.


Dichotomous choice Condorcet’s Jury Theorem Correlated votes 


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Copyright information

© Springer Science+Business Media, LLC. 2009

Authors and Affiliations

  1. 1.Austrian Institute of Economic Research (WIFO)ViennaAustria
  2. 2.Faculty of Mathematics and Computer ScienceNicolaus Copernicus UniversityToruńPoland

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