This paper considers a sequence of discrete-time random walk markets with a single risky asset, and gives conditions for the existence of arbitrage opportunities or free lunches with vanishing risk, of the form of waiting to buy and selling the next period, with no shorting, and furthermore for...

Professor Leif Johansen (1930 – 1982) made significant contributions to a large number of fields in economics. A short survey of his contributions is presented. The main focus in the paper is on his growth – production program constituting an important part of his research. The key concepts...

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...

The RAINS model is used to calculate cost minimising abatement policies subject to European-wide spatial restrictions on pollution. The principle for choosing environmental targets for the 1994 Oslo Protocol was closing a gap between benchmark- and critical loads for each grid with a uniform...

Benchmarking by means of applying the DEA model is appearing as an interesting alternative for regulators under the new regimes for electricity distributors. A sample of large electricity distribution utilities from Denmark, Finland, Norway, Sweden and the Netherlands for the year 1997 is...

A structural dynamic programming model is applied for modeling labour market transitions among older age workers in Norway in 1992-2003. Special attention is given to early retirement pensiion and disability pension as two major exit routes from the labour force. Health status is represented by...

In an in_nite horizon optimal control problem, the Hamiltonian vanishes at the in_nite horizon, when the di_erential 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...

The contributions of the paper are threefold: i) compare with mathematical rigour the Charnes, Cooper, and Rhodes DEA model and the Farrell model exhibiting constant returns to scale, ii) reinterpret the contribution of Farrell and Fieldhouse that extended the analysis to variables returns to...

This paper simulates a set of proposed policies from the Norwegian pension reform within a structural dynamic model of health and retirement estimated on the Norwegian labour market data. The paper focuses on the two main elements of the reform, namely the new pension entitlement accrual rules...