Dietrich, Franz and Spiekermann, Kai (2010): Epistemic democracy with defensible premises.

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Abstract
The contemporary theory of epistemic democracy often draws on the Condorcet Jury Theorem to formally justify the `wisdom of crowds'. But this theorem is inapplicable in its current form, since one of its premises  voter independence  is notoriously violated. This premise carries responsibility for the theorem's misleading conclusion that `large crowds are infallible'. We prove a more useful jury theorem: under defensible premises, `large crowds are fallible but better than small groups'. This theorem rehabilitates the importance of deliberation and education, which appear inessential in the classical jury framework. Our theorem is related to Ladha's (1993) seminal jury theorem for interchangeable (`indistinguishable') voters based on de Finetti's Theorem. We prove a more general and simpler version of such a theorem.
Item Type:  MPRA Paper 

Original Title:  Epistemic democracy with defensible premises 
Language:  English 
Keywords:  Condorcet Jury Theorem, dependence between voters, common causes, interchangeable voters, de Finetti's Theorem 
Subjects:  D  Microeconomics > D7  Analysis of Collective DecisionMaking > D71  Social Choice; Clubs; Committees; Associations D  Microeconomics > D7  Analysis of Collective DecisionMaking > D70  General C  Mathematical and Quantitative Methods > C0  General D  Microeconomics > D8  Information, Knowledge, and Uncertainty 
Item ID:  40135 
Depositing User:  Franz Dietrich 
Date Deposited:  18. Jul 2012 20:49 
Last Modified:  15. Feb 2013 21:24 
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URI:  http://mpra.ub.unimuenchen.de/id/eprint/40135 