It is known that majority voting among several individuals on logically interconnected propositions may generate irrational collective judgments. We generalize majority voting by considering quota rules, which accept each proposition if and only if the number of individuals accepting it exceeds...

In the theory of judgment aggregation on connected propositions, an important question remains open: Which aggregation rules are manipulable and which are strategy-proof? We define manipulability and strategy- proofness in judgment aggregation, characterize all strategy-proof aggregation rules,...

This paper studies a class of judgment aggregation rules, to be called `scoring rules' after their famous counterpart in preference aggregation theory. A scoring rule delivers the collective judgments which reach the highest total `score' across the individuals, subject to the judgments having...

This article gives a brief and informal introduction to the theory of judgment aggregation and to the discursive dilemma, focusing on methodology and interpretation.

This paper studies a class of judgment aggregation rules, to be called `scoring rules' after their famous counterpart in preference aggregation theory. A scoring rule delivers the collective judgments which reach the highest total `score' across the individuals, subject to the judgments having...

The contemporary theory of epistemic democracy often draws on the Condorcet Jury Theorem to formally justify the `wisdom of crowds'. But this theorem is inapplicable in its current form, since one of its premises -- voter independence -- is notoriously violated. This premise carries...

This paper studies a class of judgment aggregation rules, to be called 'scoring rules' after their famous counterpart in preference aggregation theory. A scoring rule delivers the collective judgments which reach the highest total 'score' across the individuals, subject to the judgments having...

When individual judgments ('yes' or 'no') on some propositions are aggregated into collective judgments, the agenda setter can sometimes reverse a collective judgment by changing the set of propositions under consideration (the agenda). I define different kinds of agenda manipulation, and...

This review article introduces and evaluates various ways to aggregate probabilistic opinions of different individuals. For each of these three ways, an axiomatic characterization result is presented (a new one in the case of multiplicative pooling). The three ways satisfy different axioms and...

How can different individuals' probability assignments to some events be aggregated into a collective probability assignment? Classic results on this problem assume that the set of relevant events -- the agenda -- is a σ-algebra and is thus closed under disjunction (union) and conjunction...