title: A network analysis of countries' export flows: firm grounds for the building blocks of the economy.
abstract: In this paper we analyze the bipartite network of countries and products from UN data on country production. We define the country-country and product-product projected networks and introduce a novel method of filtering information based on elements' similarity. As a result we find that country clustering reveals unexpected socio-geographic links among the most competing countries. On the same footings the products clustering can be efficiently used for a bottom-up classification of produced goods. Furthermore we mathematically reformulate the "reflections method" introduced by Hidalgo and Hausmann as a fixpoint problem; such formulation highlights some conceptual weaknesses of the approach. To overcome such an issue, we introduce an alternative methodology (based on biased Markov chains) that allows to rank countries in a conceptually consistent way. Our analysis uncovers a strong non-linear interaction between the diversification of a country and the ubiquity of its products, thus suggesting the possible need of moving towards more efficient and direct non-linear fixpoint algorithms to rank countries and products in the global market.
authors.affiliation: IMT-Institutions Market Technology, Lucca, Italy.
authors.forename: Guido
authors.initials: G
authors.lastname: Caldarelli
authors.forename: Matthieu
authors.initials: M
authors.lastname: Cristelli
authors.forename: Andrea
authors.initials: A
authors.lastname: Gabrielli
authors.forename: Luciano
authors.initials: L
authors.lastname: Pietronero
authors.forename: Antonio
authors.initials: A
authors.lastname: Scala
authors.forename: Andrea
authors.initials: A
authors.lastname: Tacchella