Power index research has been a very active field in the last decades. Will this continue or are all the important questions solved? We argue that there are still many opportunities to conduct useful research with and on power indices. Positive and normative questions keep calling for...

There are many situations in which different groups make collective decisions by committee voting, with each group represented by a single person. A natural question is what voting system such a committee should use. Concepts based on voting power provide guidelines for this choice. The two most...

We study the effect of public information on collective decision-making in a committee with members of both common and conflicting interests. We show that the set of preferences that allow for the existence of an informative voting equilibrium can be heavily restricted by the presence of a...

We study the effect of public information on collective decision-making in committees, where members can have both common and conflicting interests. In the presence of public information, the simple and efficient vote-your-signal strategy profile no longer constitutes an equilibrium under the...

Interest groups are introduced in a spatial model of electoral competition between two political parties. We show that, by coordinating voting behavior,these interest groups increase the winning set, which is defined as the set of policy platforms for the challenger that will defeat the...

We study the interdependence of optimal tax and expenditure policies. An optimal policy requires that information on preferences is made available. We first study this problem from a general mechanism design perspective and show that efficiency is possible only if the individuals who decide on...

When making collektive desicions, principals (voters or districts) typically benefit by strategically delegating their bargaining and voting power to representatives different from themselves. There are conflicting views in the literature, however, of whether such a delegate should be...

Interest groups are introduced in a spatial model of electoral competition between two political parties. We show that, by coordinating voting behavior, these interest groups increase the winning set, which is defined as the set of policy platforms for the challenger that will defeat the...

We set up a model of elections or referendums with two alternatives to study how voter turnout and election outcomes are affected by the publication of exit polls on election day. We find that the introduction of an exit poll influences the incentive to vote both before and after the poll is...