Vertical Price Leadership on Local Maize Markets in Benin

This paper considers vertical price relationships between wholesalers and retailers on five local maize markets in Benin. We show that if the common factor and the long-run disequilibrium error are not explicitly taken into account in testing the channel model, one can easily be wrong about how restrictions on the error-correction structure must be interpreted in terms of economic power in the channel. The empirical results show interesting differences between markets and reveal that retailers play a more prominent role in the price formation process than generally assumed in the literature. Retailers in the two major towns do not allow wholesalers to behave as vertical price leaders, but in the two larger rural centers, wholesalers involved in arbitrage among urban markets are able to influence price formation.