Template-type: ReDif-Paper 1.0
Author-Name: Dietrich Franz 
Author-Name: List Christian 
Author-workplace-name: METEOR
Title: The impossibility of unbiased judgment aggregation
Abstract: Standard impossibility theorems on judgment aggregation over logically connected propositions either use a controversial systematicity condition or apply only to agendas of propositions with rich logical connections. Are there any serious impossibilities without these restrictions? We prove an impossibility theorem without systematicity that applies to most standard agendas: Every judgment aggregation function (with rational inputs and outputs) satisfying a condition called unbiasedness is dictatorial (or effectively dictatorial if we remove one of the agenda conditions). Our agenda conditions are tight. Applied illustratively to (strict) preference aggregation represented in our model, the result implies that every unbiased social welfare function with universal domain is effectively dictatorial.
Keywords: mathematical economics; 
Series: Research Memoranda
Creation-Date: 2007
Number: 022
File-URL: http://digitalarchive.maastrichtuniversity.nl/fedora/objects/guid:f5563bdf-39d5-47f0-9f75-fcacc656cc1b/datastreams/ASSET1/content
File-Format: application/pdf
File-Size: 198908
Handle: RePEc:unm:umamet:2007022