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...

Interest groups are introduced in a spatial model of electoral competition between two political parties. We show that the presence of these interest groups increases the winning set, which is the set of policy platforms for the challenger that will defeat the incumbent. Therefore interest...

In the reported experiment different payment schemes are examined on their incentive effects. Payment based on individual, team an d relative performance are compared. Subjects conducted computerized tasks that required substantial effort. The results show that individual and team payment...

The formation of social ties is examined in an experimental study of voluntary public good provision. The experimental design consists of three parts. In the first part the value orientation (attitude to a generalized other) is measured. In the second part couples play a multi-period public good...