The theory of judgment aggregation: an introductory review

  title={The theory of judgment aggregation: an introductory review},
  author={Christian List},
  • C. List
  • Published 1 July 2012
  • Economics
  • Synthese
This paper provides an introductory review of the theory of judgment aggregation. It introduces the paradoxes of majority voting that originally motivated the field, explains several key results on the impossibility of propositionwise judgment aggregation, presents a pedagogical proof of one of those results, discusses escape routes from the impossibility and relates judgment aggregation to some other salient aggregation problems, such as preference aggregation, abstract aggregation and… 
Judgment Aggregation: A Primer
This Synthesis Lecture aims at presenting the key motivations, results, abstractions and techniques underpinning judgment aggregation, as a unifying paradigm for the formalization and understanding of aggregation problems.
A Pooling Approach to Judgment Aggregation
The literature has focused on a particular way of aggregating judgments: Given a set of yes or no questions or issues, the individuals’ judgments are then aggregated separately, issue by issue.
Rethinking the Neutrality Axiom in Judgment Aggregation
It is argued that for scenarios in which agents are asked to judge very diverse kinds of propositions, the classical neutrality axiom is much too strong, and a family of weaker neutrality axioms are proposed, parametrised by binary relations between the propositions.
Judgment Aggregation with Abstentions under Voters' Hierarchy
This paper investigates how the judgment from each individual judge affects the group judgment in an oligarchic environment and designs a feasible judgment aggregation rule based on the agents’ hierarchy that satisfies the desirable conditions.
A Modal Logic on Judgment Aggregation
A preference aggregation logic system JAL(L) is constructed using the language of the first-order logic using the basis of the judgment aggregation modal logic JAL analyzed, so that the generality of the judge aggregation model is highlighted.
Cowles Foundation for Research in Economics at Yale University Cowles Foundation Discussion Paper No . 1753 INTRODUCTION TO JUDGMENT AGGREGATION
This introduces the symposium on judgment aggregation. The theory of judgment aggregation asks how several individuals’judgments on some logically connected propositions can be aggregated into
Research on Judgment Aggregation Based on Logic
Preference aggregation and judgment aggregation are two basic research models of group decision making. And preference aggregation has been deeply studied in social choice theory. However, researches
A Hierarchical Approach to Judgment Aggregation with Abstentions
An aggregation rule based on the hierarchy of individuals is developed and it is revealed that with abstentions, oligarchic aggregation is not necessary to be a single‐level determination but can be a multiple‐level collective decision making, which partially explains its ubiquity in the real world.
Counting votes for aggregating judgments
It is shown that this is the case of the systematicity condition that prevents from electing issues with more votes than others, and a neutrality condition and a swap optimality condition are promoted.
Judgment Aggregation with Rationality and Feasibility Constraints
A model of judgment aggregation that allows for an explicit distinction between rationality and feasibility constraints is introduced and it is shown how it can be used to simulate several common voting rules in a simple and elegant manner.


Arrow’s theorem in judgment aggregation
The main aim is to identify the analogue of Arrow’s theorem in judgment aggregation, to clarify the relation between judgment and preference aggregation, and to illustrate the generality of the judgment aggregation model.
Judgment aggregation: (im)possibility theorems
Aggregation of binary evaluations
Aggregating Sets of Judgments: An Impossibility Result
Suppose that the members of a certain group each hold a rational set of judgments on some interconnected questions. And imagine that the group itself now has to form a collective, rational set of
Judgment aggregation in general logics
This methodological paper presents a generalised model of judgment aggregation, in which most realistic decision problems can be represented, and proves an impossibility theorem, which generalises earlier results.
Belief merging and the discursive dilemma: an argument-based account to paradoxes of judgment aggregation
This paper introduces a new aggregation procedure inspired by an operator defined in artificial intelligence in order to merge belief bases and shows that paradoxical outcomes arise only when inconsistent collective judgments are not ruled out from the set of possible solutions.
Judgment aggregation: A survey
Judgment aggregation is the subject of a growing body of work in economics, political science, philosophy and related disciplines. Although the literature on judgment aggregation has been in‡uenced
Group deliberation and the revision of judgments : an impossibility result
While a large social-choice-theoretic literature discusses the aggregation of individual judgments into collective ones, there is relatively little formal work on the revision of individual judgments
A generalised model of judgment aggregation
This methodological paper presents a simple unified model of judgment aggregation in general logics, and shows how many realistic decision problems can be represented in it and proves impossibility results that generalise earlier theorems.
Combining Probability Distributions: A Critique and an Annotated Bibliography
A taxonomy of solutions is presented which serves as the framework for a survey of recent theoretical developments in the area and a number of current research directions are mentioned and an extensive, current annotated bibliography is included.