A constant social discount rate cannot reflect both a reasonable opportunity cost of public funds and an ethically defensible concern for generations in the distant future. We use a model of hyperbolic discounting that achieves both goals. We imbed this discounting model in a simple climate...

Low probability catastrophic climate change can have a signifcant influence on policy under hyperbolic discounting. We compare the set of Markov Perfect Equilibria (MPE) to the optimal policy under time-consistent commitment. For some initial levels of risk there are multiple MPE; these may...

We study water regulation for a schematic water economy representing a wide range of real world situations. A water policy has inter- and intra-temporal components. The first determines the limits on extractions from the naturally replenished sources, given the stochastic nature of recharge...

Exploitation diminishes the capacity of renewable resources to with-stand environmental stress, increasing their vulnerability to extreme conditions that may trigger abrupt changes. The onset of such events depends on the coincidence of extreme environmental conditions (environmental threat) and...

Democracy tends to cultivate short-sighted politicians, for whom the horizon extends more or less till next election. This feature gives rise to a discrepancy between the time rate of discount of a country’s polity and the interest rates at which the country borrows. I show how this...