THEORY AND PRACTICE OF THE INTENSITY OF USE METHOD OF MINERAL CONSUMPTION FORECASTING (MINERAL, ECONOMICS).

摘要

The intensity of use of a mineral is traditionally defined as the consumption (production plus net imports) of the mineral divided by gross national product. It has been proposed that this ratio of raw material input to gross economic output is a predictable function of per capita income and that the relationship is based on economic theory. Though the theory has never been clearly defined, the intensity of use method has been used to make long term forecasts. This dissertation formulates a theoretical model of the consumption of minerals and the resulting intensity of use which is used to test the validity of the traditional intensity of use measure and its forecasting ability. Previous justifications of the intensity of use hypothesis state that changes in technical efficiency, substitution rates among inputs, and demands are explained by per capita income, which, as it grows, produces a regular intensity of use pattern. The model developed in this research shows that the life of the goods in use, foreign trade of raw and final goods, prices, consumer preferences, technical innovations, as well as the above factors fully explain economic use, which is not simply a function of per capita income. The complete model is used to restate the traditional theory of intensity of use and to examine the sensitivity of traditional measures to changes in the explanatory variables which are commonly omitted. The full model demonstrates the parameters that must be examined when making a long term forecast. Regular intensity of use patterns are observed for many minerals in many nations. Setting aside the theoretical questions, the intensity of use method is often used to make long term projections based on these trends in intensity of use as well as the trends in population and gross national product. This dissertation examines the forecasting ability of the traditional intensity of use method and finds that it is not necessarily an improvement over naive consumption time trend forecasts. Furthermore, it is unstable for very long term projections.