Evolution of international trade and investment from a complex network perspective

In this paper, from a perspective of complex network, we investigate the international trade and investment for more than 200 countries from 2001 to 2010. Through analyzing the topological properties, we find that the average partner numbers for both trade and investment are increasing year by year, and the average volume has a significant decrease in 2008 for investment and 2009 for trade. Although the edge density is dramatically lower and the average path length is longer for the international investment network, its clustering coefficient is higher every year. Moreover, we detect community structures and rank each country according to its total trade or investment volume, which demonstrate that the partnerships for the international trade are more stable, and USA always ranks first in its community for both trade and investment.