If estimates of mean and variance are needed and only experts' opinions are available, the literature agrees that it is wise behaviour to ask only for their (subjective) estimates of quantiles: from these, estimates of the desired parameters are calculated.Quite a number of methods have been...

This paper proves that it is wrong to require that regressing a model's outputs on the observed real outcomes gives a 45 degrees line through the origin (unit slope, zero intercept).Therefore this paper proposes an alternative requirement: the responses of the model and the real system should...

In the past China's rural areas, home to 70% of its population, suffered energy shortages.China's indigenous energy resources are limited, with the exception of coal.The widespread use of coal requires large investments in production and transport -making it costly-, and degrades the...

n practice, it is important to evaluate the quality of research, in order to make decisions on tenure, funding, and so on. This article develops a methodology using citations to measure the quality of journals, proceedings, and book publishers. (Citations are also used by the Science and Social...

Sensitivity analysis in investment problems is an important tool to determine which factors can jeopardize the future of the investment.Information on the probability distribution of those factors that affect the investment is mostly lacking.In those situations the analysts have two options: (i)...

Nowadays, every bookkeeping system used in practice is automated. Most bookkeeping software and integrated information systems are based on databases. In this paper, we develop a new conceptual bookkeeping model which is not based on manual techniques, but which is applicable in a database...

For decision makers the variability in the net present value (NPV) of an investment project is an indication of the project's risk. So-called risk analysis is one way to estimate this variability. However, risk analysis requires knowledge about the stochastic character of the inputs. For large,...