In many industrialized countries, the grocery-retailing sector exhibits a strong and increasing market concentration. Hence, it is important to understand retail pricing for many questions related to market power in the marketing chain and to agricultural and food policies. We analyze...

We analyse a stylized model of the world grain market characterized by a small oligopoly of traders with market power on both the supply and demand side. Crops are stochastic and exporting countries can impose export tariffs to protect domestic food prices. Our first result is that export...