Socially structured games

We generalize the concept of a cooperative non-transferable utility game by introducing a socially structured game. In a socially structured game every coalition of players can organize themselves according to one or more internal organizations to generate payoffs. Each admissible internal organization on a coalition yields a set of payoffs attainable by the members of this coalition. The strengths of the players within an internal organization depend on the structure of the internal organization and are represented by an exogenously given power vector. More powerful players have the power to take away payoffs of the less powerful players as long as those latter players are not able to guarantee their payoffs by forming a different internal organization within some coalition in which they have more power.we introduce the socially stable core as a solution concept that contains those payoffs that are both stable in an economic sense, i.e., belong to the core of the underlying cooperative game, and stable in a social sense, i.e., payoffs are sustained by a collection of internal organizations of coalitions for which power is distributed over all players in a balanced way. The socially stable core is a subset and therefore a refinement of the core. We show by means of examples that in many cases the socially stable core is a very small subset of the core.we will state conditions for which the socially stable core is non-empty. In order to derive this result, we formulate a new intersection theorem that generalizes the kkms intersection theorem. We also discuss the relationship between social stability and the wellknown concept of balancedness for ntu-games, a sufficient condition for non-emptiness of the core. In particular we give an example of a socially structured game that satisfies social stability and therefore has a non-empty core, but whose induced ntu-game does not satisfy balancedness in the general sense of billera

An accelerated interval method for global optimisation.

Many optimisation problems in Chemical and Process Engineering are nonconvex resulting in multiple local solutions. A modified interval algorithm for obtaining global minimisers is presented. The modifications accelerate the convergence of the interval algorithm and identify minimisers lying on constraints to provide a single rigorous globally optimal point to a general optimisation problem. The results of application to test problems indicate that a substantial performance increase is obtained when solving multiextremal problems

Pollution abatement with limited enforcement power and citizen suits

Federal environmental laws in the U.S. can be enforced by government agencies or by private parties through citizen suits against polluters. Here, I extend the standard enforcement model to examine the role played by citizen suits. The main results from the paper suggest that in a model with limited enforcement power and citizen suits the regulator fully exercises his enforcement power when the expected penalty from a citizen suit is low, but increases his reliance on citizen suits as the expected penalty rises. Whether an enforcement regime that allows private enforcement is efficient depends not only on the relative costs of private and agency enforcement, but also on the changes in inspection costs that may be caused by private enforcement and the expected penalty from losing a citizen suit. These results suggest that in practice private enforcement may lower social costs as long as relatively inexpensive agency enforcement options, such as administrative proceedings, do not preclude citizen suits. Copyright Springer Science+Business Media, LLC 2007Pollution control, Environmental regulation, Compliance, Self-reporting, Enforcement, Citizen suits, D62, L51, K32, K42, Q25,