In the global economy, crude oil is among the most important strategic goods that affects the performance of local and international markets. Prediction of the oil price has always been an important challenging topic in the global economy and producers and consumers have constantly been trying to improve their roll in the oil price changes and for many years OPEC has been one of the key players...

We study monopolistic competition under indirect additivity of preferences. This is dual to the Dixit-Stiglitz model, where direct additivity is assumed, with the CES case as the only common ground. Other examples include (perceived) demand functions that are exponential or linear. Our equilibrium results are generally in contrast with those received by the literature. An increase of the number...

Since the publication of Chamberlin's book [The Theory of Monopolistic Competition (1933)], there has been sorne controversy about what is implied by adopting the Monopolistic Competition point of view [see for example Stigler (1968, p. 320) vs. Samuelson (1958)]. The first formal model of Monopolistic Competition is due to Spence (1976). He showed that if the utility function of the sole consu...

Oil sector is the most effective sector in these countries. Oil is the most important product that world industries use as the cheapest energy. The price of oil depends on the world’s supply and demand and many economic, political and geographical variables. This is the reason why the price of oil has fluctuations. The fluctuations in oil price lead to fluctuate in the oil revenues of the membe...