A capacitated commodity trading model with market power

Abstract

In this paper we consider the problem of a trader who purchases a commodity in one market and resells it in another. The trader is capacitated: the trading volume is limited by operational constraints, e.g., logistics. The two markets quote different prices, but the spread is reduced when trading takes place. We are interested in finding the optimal trading policy across the markets so as to obtain the maximum profit in the long-term, taking into account that the trading activity influences the price processes, i.e., market power. As in the no-market-power case, we find that the optimal policy is determined by three regions, where 1) move as much as possible from one market to the other; 2) the same in the opposite direction; or 3) do nothing. Finally, we use the model to analyze kerosene price differences between New York and Los Angeles.commodity trading; price processes; inventory management;