In the main duopoly models such as that of Cournot, Bertrand and Dixit, the products are homogeneous and the price of one producer is expressed as a function of variables such as the output or the price of the other producer. However, in the real world, products are differentiated and price...

The ongoing debate between proponents of free trade and protectionism stems from the lack of the free trade and protectionism dividing line in manufacturing industries, upon which countries can agree. In this paper, we determine from a duopoly model of differentiated products this trade line,...

Following Smith's advocacy of free trade and competition, David Ricardo attempts to strengthen his theory of absolute advantage, which excludes from international trade countries which have no advantages over others, by eliminating this weakness. To do so, Ricardo introduces to the economics...