Epistemic democracy with defensible premises

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

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
• Language: English
• Keywords: Condorcet Jury Theorem, dependence between voters, common causes, interchangeable voters, de Finetti's Theorem
• Subjects: D - Microeconomics > D7 - Analysis of Collective Decision-Making > D71 - Social Choice ; Clubs ; Committees ; Associations; D - Microeconomics > D7 - Analysis of Collective Decision-Making > D70 - General; C - Mathematical and Quantitative Methods > C0 - General; D - Microeconomics > D8 - Information, Knowledge, and Uncertainty

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