In a social choice model with an infinite number of agents, there may occur “equal size” coalitions that a preference aggregation rule should treat in the samemanner.We introduce an axiom of equal treatment with respect to ameasure of coalition size and explore its interaction with common axioms of social choice. We show that, provided the measure space is sufficiently rich in coalitions of the...

Social choice rules can be used to reach group decisions in multiagent systems. We consider judgment aggregation, the problem of aggregating answers to binary logically related questions. In general ”fairness” is usually considered to be the main concern when selecting a social choice rule, however we believe that in judgment aggregation often a more relevant property is how efficient the rule ...

The literature on judgment aggregation has now been moving from studying impossibility results regarding aggregation rules towards studying specific judgment aggregation rules. Here we focus on a family of rules that is the natural counterpart of the family of Condorcetconsistent voting rules: majority-preserving judgment aggregation rules. A judgment aggregation rule is majority-preserving if ...

In [MP08] L. Marengo and C. Pasquali present a model of object construction in majority voting and show that, in general, by appropriate changes of such bundles, different social outcomes may be obtained. In this paper we extend and generalize this approach by providing a geometric model of individual preferences and social aggregation based on hyperplanes and their arrangements. As an applicat...

This paper introduces a new class of judgment aggregation rules, to be called ‘scoring rules’ after their famous counterparts in preference aggregation theory. A scoring rule generates the collective judgment set which reaches the highest total ‘score’across the individuals, subject to the judgment set having to be rational. Depending on how we de…ne ‘scores’, we obtain several (old and new) so...

Several recent articles have defined and studied judgment aggregation rules based on some minimization principle. Although some of them are defined by analogy with some voting rules, the exact connection between these rules and voting rules is not always obvious. We explore these connections and show how several well-known voting rules such as the top cycle, Copeland, maximin, Slater or ranked ...

If individual voters observe the true ranking on a set of alternatives with error, then the social choice problem, that is, the problem of aggregating their observations, is one of statistical inference. This study develops a statistical methodology that can be used to evaluate the properties of a given voting or aggregation rule. These techniques are then applied to some well-know rules.

The rank aggregation problem has been studied with varying desiderata in varied communities such as Theoretical Computer Science, Statistics, Information Retrieval and Social Welfare Theory. We introduce a variant of this problem we call distributional rank aggregation, where the ranking data is only available via the induced distribution over the set of all permutations. We provide a novel tra...

The literature on judgment aggregation has now been moving from studying impossibility results regarding aggregation rules towards studying specific judgment aggregation rules. Here we focus on a family of rules that is the natural counterpart of the family of Condorcet-consistent voting rules: majority-preserving judgment aggregation rules. A judgment aggregation rule is majority-preserving if...