Aggregation of correlated votes and Condorcet's Jury Theorem

This paper proves two theorems for homogeneous juries that arise from different solutions to the problem of aggregation of dichotomous choice. In the first theorem, negative correlation increases the competence of the jury, while positive correlation has the opposite effect. An enlargement of the jury with positive correlation can be detrimental up to a certain size, beyond which it becomes beneficial. The second theorem finds a family of distributions for which correlation has no effect on a jury's competence. The approach allows us to compute the bounds on a jury's competence as the maximum and minimum probability of it being correct for a given individual competence and dependence structure.