Monopoly in Iranian Petrochemical Industry and its Regulatory Model through “Guarantee” Contracts

In this paper, we explore the level of monopoly in petrochemical products of Iran and the fluctuations of price using the trading data of these products in Iran Mercantile Exchange (IME). Considering the level of monopoly in this market, we are looking for a solution that lowers the gap between price and quantity of current market with those of perfect competition market. Our solution is termed “Guarantee” which is a kind of security that is issued in a quantity that equates supply to market demand in the next period. This creates a two-stage game in which we satisfy the expectations for the demand of second stage in the first stage. We develop a model and show that in this
solution, the equilibrium will have lower price and higher quantity in which only the shocks of the second stage are affecting equilibrium price and quantity. Thus, in a situation without an unexpected shock, the price and quantity of market will be equal to those of perfect competition equilibrium. Moreover, we examine the underlying prediction of this new tool by analyzing the performance of an existing security called “Salaf”. These two have the nature of future trading in common and our empirical test show that introducing “Salaf” lowers prices, as predicted by theory.