If a previously unpaid activity (donating blood) is paid then we often observe that this activity is reduced. In this paper, it is hypothesised that the price offered is taken as a proxy for the "market value" of the activity. Depending on how the actor valued the activity previously,...

Shifting the responsibility for a necessary but costly action to someone else is often called Passing the Buck. Examples of such behavior in politics are environmental and budget problems which are left to future generations. Small group examples are (not) washing the dishes or (not) dealing...

The launch of a public project requires support from "enough" members of a group. Members (players) are differently important for the project and have different cost/benefit relations. There are players who profit and players who suffer from the launch of the project. Examples are the Kyoto...

In a two-stage oligopoly, with investment in the first stage and quantity or price competition in the second stage, there is a kind of Folk Theorem: We find (i) over-investment if the goods are substitutes and competition is in strategic substitutes, (ii) under-investment if we have either...