Piggins, Ashley and Duddy, Conal (2016): Oligarchy and soft incompleteness.

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Abstract
The assumption that the social preference relation is complete is demanding. We distinguish between “hard” and “soft” incompleteness, and explore the social choice implications of the latter. Under soft incompleteness, social preferences can take values in the unit interval. We motivate interest in soft incompleteness by presenting a version of the strong Pareto rule that is suited to the context of a [0, 1]valued social preference relation. Using a novel approach to the quasitransitivity of this relation we prove a general oligarchy theorem. Our framework allows us to make a distinction between a “strong” and a “weak” oligarchy, and our theorem identifies when the oligarchy must be strong and when it can be weak. Weak oligarchy need not be undesirable.
Item Type:  MPRA Paper 

Original Title:  Oligarchy and soft incompleteness 
Language:  English 
Keywords:  Oligarchy; Gibbard’s theorem; Incompleteness; Maxstar transitivity 
Subjects:  D  Microeconomics > D7  Analysis of Collective DecisionMaking > D71  Social Choice ; Clubs ; Committees ; Associations 
Item ID:  72392 
Depositing User:  Dr Ashley Piggins 
Date Deposited:  07 Jul 2016 19:27 
Last Modified:  29 Sep 2019 04:37 
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URI:  https://mpra.ub.unimuenchen.de/id/eprint/72392 