Study Of Game Model Based On Different Expectation Rules In Natural Gas Supply Market

Oligopoly exists in many countries.There are many oligopolistic industries in our country,such as energy industry,communications industry,tobacco industry,important transportation industry,news industry.There are two reasons for this situation,on the one hand,China is a country with extensive resources and large population,so it's easier to form oligopoly in the natural monopoly industry.On the other hand,in the early days China implemented planned economy,in which government controlled the production and supply of goods and the production of each commodity is franchise.Since the reform and opening,China's market economy construction has made great achievements but the competition is still not enough in many areas.Especially government is still absolutely controlled many industries which related to the people's livehood and has high industries barriers and low competition.In recent years,China has accelerated the market-oriented reform of electricity,oil and natural gas in the traditional natural monopoly industries,and government promulgated a lot of policies which will reduce industry barriers and enhance competition,but it cannot thoroughly change the situation of industry oligopoly in a short time.From the micro-level analysis,the more competitive the market structure is,the greater the consumer surplus and the total social surplus(social welfare)will be,thus competition can improve the efficiency of resources.On the contrary,the higher barriers the industries is,the lower consumer surplus will be.Studying the competition and decision-making mechanism of oligopoly enterprises has great significance to the market-oriented reform of oligopoly industry.Since Cournot put forward the famous Cournot duopoly game model,many scholars have developed the model to the three oligarchs,four oligarchs and other oligopolies on this basis or they introduce new elements into the model such as dynamic competition,incomplete information etc to further study the oligarchy game.However,these models are still too simple and the results are also more one-sided for the complex real economic system.The development of nonlinear science provides new methods and tools for scholars to study the oligopoly in the social economy,and it makes the research of the oligarchy game model more realistic.What's more,it can not only more accurately and comprehensively describe the behavior of oligarchy in reality,and also be a more profound explanation of the internal mechanism of oligarchy and the nature of competition.In practice,a good economic model should be able to correctly and comprehensively reflect the actual economic operation,to help the economic master to grasp the law and the nature of economic development,and to provide theoretical basis for the decision-makers in the enterprise.An oligopoly dynamic game model based on different expectation rules were established in natural gas supply market in the paper.The system equilibrium was calculated by nonlinear dynamical system theory and then analyzed the stability of the system.In the end,analyzing the system behavior deduced by the change of main-parameters by the numerical simulation method and analyzing the rationality of the model by comparing with adopting consistent strategy.The results showed that the game model has a very complicated dynamic characteristics.And fast changing of bounded rationality parameter can make the chaos occur in advance.It is good for the system stability if the self-adaption is properly adjusted.