An economy faces an unknown individual risk, such as the health effects of a recently discovered environmental hazard. Opinions may be widely different about the distribution of risks across the population. We study financial markets that suffice to reach efficient allocations in this situation....

We study paths which involve optimal use of a renewable resource under several alternative definitions of optimality, including the discounted utilitarian, Chichilnisky's, the Rawlsian and the green golden rule. Initially we consider an economy where the only good is the resource: subsequently,...

We address the problem of optimal use of renewable resources under a variety of assumptions both about the nature of the economy in which these resources are embedded and about the objective of that economy. In this second respect, we are particularly interested in investigating the consequences...

We study a growth model with an environmental asset which is a source of utility and an input to consumption and production. The stock of this asset follows its own ecological dynamics, which are affected by economic activity. We study the implications of an approach to ranking sequences of...

We study a growth model with an environmental asset which is a source of utility and an input to consumption and production. The stock of this asset follows its own ecological dynamics, which are affected by economic activity. We study the implications of an approach to ranking sequences of...

New risks seem to be an unavoidable in a period of rapid change. The last few decades have brought us the risks of global warming, nuclear meltdown, ozone depletion, failure of satellite launcher rockets, collision of supertankers, AIDS and Ebola. A key feature of a new risk, as opposed to an...

A single condition, limited arbitrage, is shown to be necessary and sufficient for the existence of a competitive equilibrium and the core in economies with any number of markets, finite or infinite, with or without short sales. This extends earlier results of Chichilnisky for finite economies....