The Scaled Model of Error has gained considerable popularity during the past ten years as a device for computing probabilistic population forecasts of the cohort-component type. In this report we investigate how sensitive probabilistic population forecasts produced by means of the Scaled Model...

A system of regression equations (SURE) for analyzing panel data with random heterogeneity in intercepts and coefficients, and unbalanced panel data is considered. A Maximum Likelihood (ML) procedure for joint estimation of all parameters is described. Since its implementation for numerical...

Applications of the DEA models show that inadequate results may arise in some cases, two of these inadequacies being: a) too many efficient units may appear in some DEA models; b) a DEA model may show an inefficient unit from the point of view of experts as an efficient one. The purpose of this...

The two fund separation property of the elliptical distributions is extended to the skew-elliptical and by adding a number of funds equalling the rank of the skewness matrix. Some elements of the generalization to singular extended skew-elliptical distributions are covered.

Measuring productive efficiency is an important research strand within fields of economics, management science and operations research. One definition of efficiency is the proportional scaling needed for observations of an inefficient unit to be projected onto an efficient production function...

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...

The pseudo-isotropic multivariate distributions are shown to satisfy Ross’ stochastic dominance criterion for two-fund monetary separation. The classical case of separation under abence of risk-free investment opportunity, admits a few particular generalizations to k-fund separation 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...