In this paper we develop and estimate an empirical model of pricing behavio
ur for food retail firms in both a quantity-setting oligopoly engaged in th
e joint production of demand-related final goods and a quantity-setting oli
gopoly for supply-unrelated wholesale goods. The procedure consists of esti
mating an inverse demand system for the final goods, single supply function
s for the wholesale goods and the retail industry first-order profit-maximi
sation conditions, from which an estimate of the degree of imperfect compet
ition and of oligopoly-oligopsony power for the different commodities can b
e retrieved. The model is applied to the French food retail industry and th
ree commodities are distinguished: dairy products, meat products and other
food products. We strongly reject the hypothesis that French food retail fi
rms behave competitively, and more than 20 and 17 per cent of the wholesale
-to-retail price margins for dairy products and meat products, respectively
, can be attributed to oligopoly-oligopsony distortions.