Prix, profit et développement économique. Problèmes de l'optimum global

Résumé En

Prices, profit and economic growth prorlems of the gloral optimum Optimisation problems are now studied either in a partial equilibrium setting, or in highly abstract general theories inapplicable to economic reality. The value of the partial studies is limited by the assumptions they have to make about such things as prices and the behaviour of interest rates. Even greater problems arise if our concern is with medium or long term forecasting for the economy as a whole. If we begin from technological and sociological conditions, a wide range of equally plausible assumptions might be made about the evolution of such matters as technical development, the structure of consumption, external trade, etc. It is therefore necessary to compare the quantitative results that different assumptions ivould give, not in order to derive absolute criteria for policy but to specific questions. The author uses such a procedure to examine the optimisation problems arising, first in an economy with perfect foresight, and then in one with imperfect foresight. In neither case can a firm basis be found for choosing between the different options which any model must leave open. In particular, we are left with two general questions : what system of prices should be used to make volume comparisons ? What interest rate should be used in calculations of present value ? In addition, if forecasting is imperfect, the econometric models we can use must necessarily be very rough, and it becomes impossible adequately to restrict the range of possible assumptions about such matters as the evolution of consumption. The author concludes that it might be possible to provide a firmer basis for forecasting over say, a five-year period, by greater systematisation of technical information. For longer periods, many important decisions must involve a gamble : at best, these decisions, once taken, might themselves be treated as the basis for optimisation calculations.