In the minimum cost spanning tree model we consider decentralized pricing rules, i.e. rules that cover at least the efficient cost while the price charged to each user only depends upon his own connection costs. We define a canonical pricing rule and provide two axiomatic characterizations....

In river systems, costly upstream pollution abatement creates downstream welfare gains. Absent adequate agreement on how to share the gains, upstream regions lack incentives to reduce pollution levels. We develop a model that makes explicit the impact of water quality on production benefits and...

In river systems, costly upstream pollution abatement creates downstream welfare gains. Absent adequate agreement on how to share the gains, upstream regions lack incentives to reduce pollution levels. We develop a model that makes explicit the impact of water quality on production benefits and...

This paper deals with the issue of how to allocate greenhouse gas emission permits to nations in the long run. The so-called "equitable" rules to allocate such permits under a global agreement (per capita or grandfathering allocation rules for instance) do not necessarily ensure stability in the...

We discuss the welfare effects of bundling two products offered by two symmetric firms. We first show that, in terms of welfare, a monopoly does better than a duopoly in which each firm sell its good and that a monopoly selling the bundle does better than if it sells the bundle and the two goods...