We axiomatically study voting rules without making any assumption on the ballots that voters are allowed to cast. In this setting, we characterize the family of ''endorsement rules", which includes approval voting and the plurality rule, via the imposition of three normative conditions. The...

We axiomatically study voting rules without making any assumption on the ballots that voters are allowed to cast. In this setting, we characterize the family of “endorsement rules,” which includes approval voting and the plurality rule, via the imposition of three normative conditions. The...

We provide an axiomatic characterization of the core of games in effectiveness form. We point out that the core, whenever it applies to appropriate classes of these games, coincides with a wide variety of prominent stability concepts in social choice and game theory, such as the Condorcet...

The “Coase theorem” is made of the efficiency and the neutrality theses. Using cooperative game theory, we show that these two theses are not compatible: there exist only two types of rights assignments that guarantee a nonempty core. Thus, the efficiency thesis holds – there exist (two...