In this paper we study hedonic games where each player views every other player either as a friend or as an enemy. Two simple priority criteria for comparison of coalitions are suggested, and the corresponding preference restrictions based on appreciation of friends and aversion to enemies are...

The present stalemate in climate negotiations has led policy analysts and economists to explore the possible emergence of alternative climate regimes. This paper explores the idea of replacing international cooperation on greenhouse gas emission control with international cooperation on...

We examine the formation of networks among a set of players whose payoffs depend on the structure of the network. We focus on games where players may bargain by promising or demanding transfer payments when forming links. We examine several variations of the transfer/bargaining aspect of link...

We study a game theoretic model of a parliamentary democracy under proportional representation where `citizen candidates' form parties, voting occurs and governments are formed. We study the coalition governments that emerge as functions of the parties' seat shares, the size of the rents from...

We define the canonical form of a cost spanning tree problem. The canonical form has the property that reducing the cost of any arc, the minimal cost of connecting agents to the source is also reduced. We argue that the canonical form is a relevant concept in this kind of problems and study a...

This paper analyses stability of coalitions for greenhouse gas abatement for different sharing rules applied to the gains from co-operation. We use a 12-regions model designed to examine internal and external stability of coalitions (STACO). We compare different sharing rules like, for example,...

We consider a simple dynamic model of environmental taxation that exhibits time inconsistency. There are two categories of firms, Believers, who take the tax announcements made by the Regulator to face value, and Non-Believers, who perfectly anticipate the Regulator's decisions, albeit at a...

Nowadays, a process can be observed in Germany where electricity producing and trading firms react to the electricity market liberalisation by merging market shares, since the year 2000, which reduces the number of suppliers and influences production and consumer prices. This paper discusses...

We study the group stability of collective decision making when society is organized according to a non directed graph, and groups' payoff possibilities are given by a partition function. We focus on the stability properties of hierarchical organizations, formally described by minimally...

Much of the literature on international environmental agreements uses static models, although most important transboundary pollution problems involve stock pollutants. The few papers that study IEAs using models of stock pollutants do not allow for the possibility that membership of the IEA may...