Complex Systems and Networks: from Graph Theory to the World Trade Web

The modern science of networks has brought significant advances to our understanding of complex systems. The World Trade Web (WTW) is the complex network representation of the international trade system that allows an analysis at the large scale from an interdisciplinary approach. Countries are represented as nodes and commercial relations between them as links. The network representation offers a new level of description that goes beyond the country-specific analyses used in more traditional economic studies of trade. In this line of research, several tools and methodologies - recently developed in the framework of network science - can be exploited to extract information from the WTW, and to discriminate which properties signal a nontrivial structural organization and which are likely originated by chance or structural constraints. Recent network-inspired models that succeed in explaining the observed complexity of the WTW at a topological level will be discussed, together with some open questions for future research.