25 November 2011, Computational Social Choice Seminar, Irem Bozbay

Abstract

We analyse the problem of aggregating judgments over multiple issues from the perspective of efficient aggregation of voters' private information. While new in judgment aggregation theory, this perspective is familiar in a different body of literature about voting between two alternatives when voters' disagreements stem (fully or partly) from conflicts of information rather than interests. Combining the two literatures, we consider a simple judgment aggregation problem and model the private information underlying voters' judgments. We analyse the resulting strategic incentives and determine which voting rules lead to collective judgments that efficiently use all private information, assuming that voters share a preference for true collective judgments. We find that in many, but not all cases a quota rule should be used, which decides on each issue according to whether the proportion of `yes' votes exceeds a particular quota. This is joint work with Franz Dietrich and Hans Peters

For more information, see http://www.illc.uva.nl/~ulle/seminar/ or contact Ulle Endriss (ulle.endriss at uva.nl).