Echantillonnage représentatif optimum à probabilités inégales

In this paper the Caines-Keng-Sethi procedure is used to investigate the dynamic relationships between Rotterdam prices for the main products of animal feed. Results show that (i) Dynamic price relationships highlight substitution and complementarity relationships among the various products and results seem consistent with nutritional compositions. (ii) Corn-gluten-feed behaves as a substitute for both protein and energy rich products. (iii) The only significative influence of variations in the $-Ecu exchange rate is on the price of corn-gluten-feed.