A Study On Supply Chain Credit Risk Contagion And Prevention Based On Scale-Free Network Theory

In the context of economic globalization,enterprises face more intense market competition and more complex and varied internal and external environments.Their partners and competitors are no longer confined to one area,but gradually expand globally.In this process,the supply chain system composed of upstream and downstream enterprises gradually replaced a single enterprise becoming a competitive entity.And along with companies in different supply chains are related by funds,business,information and etc,the relationship of cooperation and competition of supply chains is no longer limited to a single supply chain.Simultaneously,in recent years,With the increasing frequency of credit risks,the stability of the supply chain has been severely challenged.Moreover,different supply chains form a supply chain network due to the relationship between enterprises,which further increases the contagion range and influence level of credit risk.For example,in 2016,LeTV broke out credit risk and caused a huge impact on its creditors,suppliers and agents.Then credit risk spread along the relationship chain between.Ultimately,it had a huge impact on the entire supply chain network,and leaded to a large number of enterprises breaking out credit risks and even closing down.It can be seen that the supply chain network node enterprises not only have to face the credit risk contagion of upstream and downstream enterprises,but also need to face the cross-contagion of credit risks of other related enterprises in the supply chain network,which leads to the credit risk prevention and control of credit risks becoming more complicated and difficult.Therefore,measuring and analyzing credit risk contagion from the perspective of supply chain network,and proposing a credit risk prevent and strategy based on this,will have certain theoretical and practical value.Firstly,this paper summarizes the mechanism,influencing factors,ways,strengths of supply chain credit risk contagion and scale-free network theory and network characteristics.Secondly,this paper analyzes the credit risk contagion of partial supply chain network,which is that the credit risk in the supply chain network only has one-way infection and one indirect infection(that is only one intermediate enterprise in the process of infection),and theoretically deduce the credit risk measurement model of partial supply chain network by using the simplified model of J Yu and combining with the scale-free characteristics of the supply chain network.Then analyzing the probability of credit risk outbreak of related enterprises when the credit risk occurs in enterprises on the part supply chain network,and the impact of different supply chain structure on credit risk contagion.Third,the research on supply chain credit risk contagion is extended to the general supply chain network,which is that there is dynamic and feedback infection of credit risk in the supply chain network.This paper combines the scale-free network theory with the SEIRS infectious disease model in the medical field,constructing the credit risk infection model of the supply chain network,and then,analyzing the situation of the status of the supply chain network node enterprises and factors affecting credit risk transmission in the process of credit risk infection.Then,this paper use Matlab to simulate the credit risk contagion model,and use the way Quantitative analysis to study the impact of preexisting prevention and control capabilities of credit risk of supply chain network node enterprises,the network average degree of supply chain networks and the scale of supply chain networks on the credit risk contagion of supply chain networks.Finally,the simulation results are tested by an example.Research results of credit risk contagion in partial supply chain networks indicate: compared to that there is only direct infection,when there is indirect infection between enterprises,related enterprises are more easier affected by credit risk and the probability of credit risk outbreak is higher.And there are some factors that are positively related to the probability of credit risk outbreak of related enterprises,which are the direct contagion factors and indirect contagion factors of credit risk among related enterprises and the average degree of supply chain network nodes.Matlab simulation was carried out on the general supply chain network credit risk contagion model,and it was found that the network characteristics of supply chain would affect credit risk contagion: When the average degree of supply chain network nodes is k>80,it is positively correlated with the infection rate and scale of supply chain credit risk;When the average degree is k?80,the supply chain network has the strongest ability to prevent and control credit risk and can effectively control the infection of credit risk.When the supply chain network size N?13000,N is negatively correlated with the infection rate and scale of supply chain credit risk;When the supply chain network size is N?13000,the infection rate and scale of supply chain credit risk do not change with the change of N.This shows that when N=13000,the scale of the supply chain network is optimal,and at this time,it has the strongest resistance to supply chain credit risk.And,the results of the example test are consistent with the results of the Matlab simulation.In addition,the node enterprise adopts effective credit risk prevention and control measures in advance to effectively reduce the its own impact of credit risk contagion and enhance its immunity to credit risk infection.Finally,this paper proposes practical strategies to supply chain credit risk prevention and control for supply chain network node enterprises and supply chain network systems.The main contributions of this article are:(1)Applying the scale-free network theory to the credit risk contagion research of supply chain network,it highlights the scale-free characteristics of the supply chain network and is more in line with the characteristics of supply chain credit risk contagion.(2)The SEIRS infectious disease dynamics model in the medical field was applied to the supply chain network credit risk contagion research.It accurately depicts the complexity of supply chain credit risk contagion dynamics,interaction,feedback,etc.,and the impact of the scale of the supply chain network and the network average on credit risk contagion was analyzed from the global rather than the local.