Existing theoretical and experimental studies have established that unanimity is a poor decision rule for promoting information aggregation. Despite this, unanimity is frequently used in committees making decisions on behalf of society. This paper shows that when committee members are exposed to...

There are many situations where different groups make collective decisions by voting in an assembly or committee in which each group is represented by a single person. There is a great deal of theoretical, normative literature on the question of what voting system such an assembly should use,...

This paper examines how neutral the current EU decision-making procedures are to membership and how well they obey certain transparent general constitutional principles. The paper evaluates the performance of the procedures by strategic and classical power indices. The main emphasis in the...

In this paper we address several issues related to collective dichotomous decision-making by means of quaternary voting rules, i.e., when voters may choose between four actions: voting yes, voting no, abstaining and not turning up-which are aggregated by a voting rule into a dichotomous...

It is known that on some social choice and economic domains, a social choice function is coalition strategy-proof if and only if it is Maskin monotonic (e.g. Muller and Satterthwaite, 1977). This paper studies the foundation of those results. I provide a set of conditions which is sufficient for...

This paper examines how neutral the current EU decision-making procedures are to membership and how well they obey certain transparent general constitutional principles. The paper evaluates the performance of the procedures by strategic and classical power indices. The main emphasis in the...

A common real-life problem is to fairly allocate a number of indivisible objects and a fixed amount of money among a group of agents. Fairness requires that each agent weakly prefers his consumption bundle to any other agent's bundle. In this context, fairness is incompatible with budget-balance...

We study international free-riding-proof coalitions to solve trans-boundary environmental problems such as global warming. We show that the free-riding problem is rather serious so that a free-riding-proof coalition can consist of only a small number of countries. In the optimal coalitional...

In a matching problem between students and schools, a mechanism is said to be robustly stable if it is stable, strategy-proof, and immune to a combined manipulation, where a student first misreports her preferences and then blocks the matching that is produced by the mechanism. We find that even...

Weighted committees allow shareholders, party leaders, etc. to wield different numbers of votes or voting weights as they decide between multiple candidates by a given social choice method. We consider committees that apply scoring methods such as plurality, Borda, or antiplurality rule. Many...