n an infinite horizon optimal control problem, the Hamiltonian vanishes at the infinite horizon, when the differential equation is autonomous. The integrand in the integral criterion may contain the time explicitly, but it has to satisfy certain integrability conditions. A generalization of...

Piecewise deterministic control problems are problems involving stochastic disturbance of a special type. In certain situations, in an otherwise deterministic control system, it may happen that the state jumps at certain stochastic points of time. Examples are sudden oil finds, or sudden...

US shale gas production is generally expected to continue its fast rise. However, a cautious evaluation is needed. Shale gas resource estimates are potentially overoptimistic and it is uncertain to which extent they can be produced economically. Moreover, the adverse environmental effects of...

We present a medium-term market equilibrium model of the North American crude oil sector via which we develop a scenario analysis to investigate strategies to mitigate the environmental and public-safety risks from crude-by-rail transportation across the United States. The model captures crude...

Coal consumption and production have sharply declined in recent years in the U.S., despite political support. Reasons are mostly unfavorable economic conditions for coal, including competition from natural gas and renewables in the power sector, as well as an aging coal- fired power plant fleet....

In this paper we examine the role of mortgage equity withdrawal in explaining the decline of the US saving rate, since when house prices rise and mortgage rates are low, homeowners have an incentive to withdraw housing equity and this may affect the saving rate. We estimate a Vector Error...

We use Norwegian register data from 1989 to 2002 to estimate the causal effects of programme participation on the transition rate from unemployment to employment,by means of a dependent risks hazard rate model. The separate roles of causality and unobserved heterogeneity are non-parametrically...

Based on a combined register database for Norwegian and Swedish unemployment spells, we use the ‘between-countries-variation’ in the unemployment insurance systems to identify causal effects. The elasticity of the job hazard rate with respect to the benefit replacement ratio is around -1.0...

Building on register data describing monthly labour market status for the whole Norwegian population 1992-95, we estimate grouped competing risk hazard rate models for transitions between employment, unemployment and non-participation. The models impose no parametric restrictions on either...

We use Norwegian micro-data to identify the driving forces behind unemployment spells following temporary- and permanent dismissals. The duration of unemployment spells for permanently dismissed workers is primarily explained by individual resources and economic incentives, while spell-duration...