A Kopel duopoly model for competition in advertisement is developed, and it is found that the advertising behavior of enterprises may result in the instability or even chaos of the market.

With the development of China deploying the third generation mobile telecommunication, more latent entrant will entry into China mobile market which is now composed with duopoly mobile operations, China Mobile and China Unicom.

It is shown that under a certain hypothesis of market, the slope of reaction function in duopoly model is between - 1 and 0, which leads to possible unstability for Cournot equilibrium.

Then it considers two types of oil market structure:Cournot duopoly (F and M set their oil supply or price simultaneously) and perfect competition.

Option games model of firm′s investment strategy in oligopoly;

The Impact of Competitor Information on the Equilibrium of Cournot Oligopoly:An Experimental Study;

Oligopoly and Initiate Allocation of Emission Right;

In the time of knowledge economy, oligarch monopoly induced by technological monopoly is happened in China market, but it s multinational corporations who take up the oligarch place and get the large profit.

Chinese insurance industry is an oligarch monopoly industry.

Analysis on Duopoly under Nonlinear Pricing to Product;

Duopoly,Nonlinear Pricing and Asymmetrical Equilibrium

The influence of the first kind of market authority,namely permitting price operation on emissions trading plan is discussed under the conditions of duopoly.