Research On Project Portfolio Risk Model Based On The Interaction Effect

In order to maintain the competitive advantage and sustainable growth,coordinating the management of multiple projects has become a common corporate behavior.The problem of project portfolio management come into being. How to accurately depict the project portfolio risk has important significance for the project portfolio management.Different from the single project risk, the project portfolio risk study must consider the risk interaction effect. With the gradual expansion of the application scope of the population ecosystem model, at present, few researchers have studied the project portfolio risk based on the similarity between the project reliability(risk inverse) and the population trend growth of the mutual benefit system model. In this thesis, three kinds of project portfolio risk system based on different factors are established. The content is as follow:Firstly, by the aid of ecological model with stage structure, the single project risk model having the characteristics of stage structure and sparse effect is established. Global stability of equilibrium point of the model are given by using the qualitative and stability theory of differential equation and a Lyapunov function. The risk degree and trend of the project are presented, which provides a theoretical basis for the effective identification and avoidance of project risk.Secondly, to research the project portfolio risk with stage structure under the interaction effect, project portfolio risk model with stage structure is established under the interaction effect by means of biological population dynamics theory, then, the sufficient conditions for the global stability of the equilibrium point of the system and the corresponding persistence are obtained, and the real-time characterization of project portfolio risk system is achieved. Meanwhile, the validity of the method is verified through the numerical simulation.Finally, based on the interaction of three project portfolio risk model is established.By using the qualitative and stability theory of differential equation, the research about characterization and trend analysis of project portfolio risk real-time are studied. It lays the foundation for further research about multiple portfolio risk model.From the view of theory, the results from the point of single point are extended to continuous time. At the same time, the quantitative methods of the interaction of three project portfolio risk characterization are provided. From the view of the application, theapplication range of population ecology system is extended to project portfolio risk, the corresponding theory and method for controlling the risk for decision maker are given. Of course, there are certain limitations, for example considering of stochastic factors, time lag and other factors, the multiple project portfolio risk system model need to be further studied by researchers.