This paper formulates a Condorcet Jury Theorem and emphasizes the necessity of the condition of boundedness away from one-half or staying away from fair coins. <!--ID="" Acknowledgement. This paper was presented at the 1996 European Public Choice Meeting, Tiberias, Israel and benefited from the helpful comments of the participants, especially those of Hannu Nurmi. The author also acknowledges the helpful comments of Daniel Berend and an anonymous referee.-->

This paper provides first the condition under which the majority of an odd number of jurists is more likely to choose the better of two alternatives than a single jurist selected at random from the jurists, given that each jurist has a probability larger than one half of choosing correctly, and...

According to Condorcet, the larger the team of decision-makers using the simple majority rule, the more likely they are to reach correct decisions. This paper examines the validity of this claim under the condition of reduced team competence with size. Determining committee size always involves...

This paper derives optimal decision rules for fixed-size committees in polychotomous choice situations. Earlier studies focus on the dichotomous choice model and thus the present extension broadens the scope of applications of the theory of collective decision making.

Existing proofs of Condorcet's Jury Theorem formulate only sufficient conditions for its validity. This paper provides necessary and sufficient conditions for Condorcet's Jury Theorem. The framework of the analysis is the case of heterogeneous decisional competence, but the independence...