Judgment aggregation and agenda manipulation

Abstract: When individual judgments (‘yes’or ‘no’) on some propositions are aggregated into collective judgments, outcomes may be sensitive to the choice of propositions under consideration (the agenda). Such agenda-sensitivity opens the door to manipulation by agenda setters. I de…ne three types of agenda-insensitivity (‘basic’, ‘full’, and ‘focal’) and for each type axiomatically characterize the aggregation procedures satisfying it. Two axioms turn out to be central for agenda-insensitivity: the familiar independence axiom, requiring propositionwise aggregation, and the axiom of implicit consensus preservation, requiring the respect of any (possibly implicit) consensus. As the paper’s second contribution, I prove a new impossibility theorem whereby these two

• Type: Journal
• Year: 2016
• Where: GEB
• Authors: Franz Dietrich
• Keywords: GEB 2016