Les marchés physiques et l'organisation des marchés

Abstract

[eng] In France today, in the case of four groups of farm commodities (fruits and vegetables, flowers and ornemental plants, live animals and fish) physical markets remain the basis of price formation and the locus of effective competition. They are aforum for operators, provide a sensitive index of the state of supply and demand detect domination effects and are a springboard for entry into the field. They constantly remind firms, organizations and governments about economic reality. For perishables of varying quality and fluctuating supply physical markets are not likely to disappear. Their modernization is linked with the level of global regulation of the economy. [fre] Aujourd'hui en France, les marchés physiques, soit sous leur forme traditionnelle de gré à gré ou de vente à la criée, soit sous leur forme modernisée d'enchères électroniques, sont toujours la base de laformation des prix et le support privilégié d'une concurrence effective rabotant les rentes, dans quatre secteurs de l'économie agricole (fruits et légumes, fleurs et plantes, animaux vivants et poissons). Forum des opérateurs, baromètre de la conjoncture, révélateurs des effets de domination, pistes d'entrée dans les branches, ils rappellent sans cesse les entreprises et les pouvoirs publics à la réalité économique. Détecteurs de la vérité des prix, ils signalent les dérapages bureaucratiques. Pour les produits périssables à qualité variable et à offre fluctuante, la disparition des marchés physiques est improbable, mais leur modernisation imperative, car liée à l'évolution de la régulation économique générale.

An analysis of price formation in the Dutch mussel industry

“…Individual producers inform the PO 48 h in advance of the tonnage of their cargo, which constitutes an auction lot, where it is from and the day of delivery to the auction This information is made available to all buyers Before the auction, samples are taken from each shipload to ensure they meet certain minimum quality standards For the 1991/92 season these were a minimum 35% of mussels larger than 50 mm and a minimum meat content of 16% Those lots which do not meet the reqmred criteria are taken back by the producer or bought at a withdrawal price by the PO Thin product m rela]d on sea-beds and m sold at the end of the marketing season The withdrawal price m fixed by the PO and financed by a levy on the producers Prices are formed through a decreasing-price auction where there is no collusion between either suppliers or buyers A decreasing-price auchon starts at the highest price, which is gradually reduced until someone bids Thin bidder is allocated the lot Sales are conducted in the order of the arrival of boats and are carried out by electronic bidding by buyers The single highest offer wins the lot and this bid m made public with all other bids remaining secret This method of setting the price prowdes a price very close to a competitive price (Lauret and Soufflet, 1985, Naegelen, 1985, Opstelten, 1985 Naegelen (1985) uses game theory analysis to study the Dutch auction market properties She compares a decreasing auction to a non-cooperatwe game Assuming risk-averse behavlour amongst buyers, which is fairly likely with perishable goods, the resulting price m shown to be the most compehhve price for the actual supply-anddemand situation A buyer is faced with a trade-off between mm]mlzmg the buying price and maximizing the probability of obtaining the lot The higher the bid, the more likely the buyer is to gain the auctioned lot However, the lower he bids, the more he is maximizing the difference between the maximum price he is prepared to pay and the actual price he does pay Naegelen shows that a rink-averse buyer is likely to interrupt the fall m price at their personal maximum paying price, thereby mammlzmg the probabdlty of obtaining the lot…”