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Are qualified majority rules special?


This essay provides a formal justification for qualified majority rules. Specifically, within an uncertain dichotomous choice framework, in which individual preferences are identical but actual judgments may differ, special majority rules emerge as decision rules that maximize the probability of making correct decisions. The main result specifies the optimal special majority as a function of a priori bias in favor of the status quo, ability, and size of the decision-making body. The analysis of the relationships among these three variables in generating certain common qualified majority rules is then pursued.

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We would like to acknowledge the particularly helpful suggestions of Peter Aranson. We are also indebted to the anonymous referees for their comments.

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Nitzan, S., Paroush, J. Are qualified majority rules special?. Public Choice 42, 257–272 (1984).

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  • Decision Rule
  • Public Finance
  • Majority Rule
  • Individual Preference
  • Correct Decision