Since then, I have extended this model further, especially in collaboration with Franz Dietrich. We have proved several impossibility and possibility theorems, generalizing earlier results in social choice theory, including Arrow's impossibility theorem, Sen's theorem on the impossibility of a 'Paretian liberal', a variant of the Gibbard-Satterthwaite theorem on strategic manipulation, a variant of a median voter theorem, and Sen's possibility theorem on majority voting on restricted domains.

More recently, we have studied problems of general attitude aggregation as well as probabilistic opinion pooling. I've also applied ideas from judgment-aggregation theory to the problem of the transformation of judgments in group deliberation.

Highlights

Probabilistic Opinion Pooling Generalized -- Part One: General Agendas (with F. Dietrich), Social Choice and Welfare 48(4): 747-786, 2017

Probabilistic Opinion Pooling Generalized -- Part Two: The Premise-based Approach (with F. Dietrich), Social Choice and Welfare 48(4): 787-814, 2017

Probabilistic opinion pooling [an introductory review] (with F. Dietrich), Oxford Handbook of Probability and Philosophy, 2016

Aggregating Causal Judgements (with R. Bradley and F. Dietrich), Philosophy of Science 81: 491-515, 2014

Propositionwise judgment aggregation: the general case (with F. Dietrich), Social Choice and Welfare 40(4): 1067-1095, 2013

The theory of judgment aggregation: An introductory review, Synthese 187(1): 179-207, 2012

The Logical Space of Democracy, Philosophy and Public Affairs 39(3): 262-297, 2011

Group Communication and the Transformation of Judgments: An Impossibility Result, Journal of Political Philosophy 19(1): 1-27, 2011

The aggregation of propositional attitudes: towards a general theory (with Franz Dietrich), Oxford Studies in Epistemology 3, 2010

Majority voting on restricted domains (with Franz Dietrich), Journal of Economic Theory 145(2): 512-543, 2010

A liberal paradox for judgment aggregation (with Franz Dietrich), Social Choice and Welfare 31: 59-78, 2008

Arrow's theorem in judgment aggregation (with Franz Dietrich), Social Choice and Welfare 29(1): 19-33, 2007

Strategy-proof judgment aggregation (with Franz Dietrich), Economics and Philosophy 23(3): 269-300, 2007

Aggregating Sets of Judgments: An Impossibility Result (with Philip Pettit), Economics and Philosophy 18: 89-110, 2002 (see also companion paper in Synthese 2004)

Introductory papers

[non-technical] Judgment aggregation: a short introduction, in U. Maki (ed.), Handbook of the Philosophy of Economics, Amsterdam (Elsevier)

[non-technical] The Discursive Dilemma and Public Reason, Ethics 116(2): 362-402, 2006

[non-technical] Group knowledge and group rationality: a judgment aggregation perspective, Episteme: A Journal of Social Epistemology 2(1): 25-38, 2005

[slightly more technical] Judgment aggregation: a survey (with Clemens Puppe), in P. Anand, C. Puppe and P. Pattanaik (eds.), Oxford Handbook of Rational and Social Choice, Oxford (Oxford University Press), 2009

[more technical] Introduction to judgment aggregation (with Ben Polak), Journal of Economic Theory 145(2): 441-466, 2010 

Other papers  

Probabilistic Opinion Pooling Generalized -- Part One: General Agendas (with F. Dietrich)

Probabilistic Opinion Pooling Generalized -- Part Two: The Premise-based Approach (with F. Dietrich)

(these two papers draw on the earlier working paper Opinion pooling on general agendas, with F. Dietrich, 2007/2008)

When to defer to supermajority testimony -- and when not, in J. Lackey (ed.), Essays in Collective Epistemology, Oxford (Oxford University Press) (forthcoming)

Judgment aggregation with consistency alone (with Franz Dietrich), 2007

The impossibility of unbiased judgment aggregation (with Franz Dietrich), Theory and Decision 68(3): 281-299, 2010

Collective wisdom: a judgment aggregation perspective, in Hélène Landemore and Jon Elster (eds.), Collective Wisdom: Principles and Mechanisms (forthcoming)

Judgment aggregation under constraints (with Franz Dietrich), in T. Boylan and R. Gekker (eds.), Economics, Rational Choice and Normative Philosophy, London (Routledge), 2008

Judgment aggregation without full rationality (with Franz Dietrich), Social Choice and Welfare 31: 15-39, 2008

Which worlds are possible? A judgment aggregation problem, Journal of Philosophical Logic 37: 57-65, 2008

Judgment aggregation by quota rules: majority voting generalized (with Franz Dietrich), Journal of Theoretical Politics 19(4): 391-424, 2007

The Probability of Inconsistencies in Complex Collective Decisions, Social Choice and Welfare 24(1): 3-32, 2005

A Model of Path-Dependence in Decisions over Multiple Propositions, American Political Science Review 98(3): 495-513, 2004

Aggregating Sets of Judgments: Two Impossibility Results Compared (with Philip Pettit), Synthese 140(1-2): 207-235

A Possibility Theorem on Aggregation over Multiple Interconnected Propositions, Mathematical Social Sciences 45(1): 1-13 (important correction)