I. Introduction
The current economic crisis illustrates a critical need for a new and fundamental understanding of the structure and dynamics of economic systems [1]– [3]. The global economic system, as any other complex systems, reflects a dynamic interaction of a large number of economic entities [4]. To facilitate policy designs that reduce conflict between individual interests and global efficiency, it is necessary to address the systemic complexity in the economic systems, in which the dynamics of financial contagion is one of the most important problems attracting attentions.