Do trading countries also collaborate in R&D? This is the question that, facing with a number of methodological problems, here it is dealt with. Studying and comparing the international trade network and the R&D collaboration network of European countries in the aerospace sector, social network analysis offers a wide spectrum of methods and criteria either to make them comparable or to evaluate its similarity. International trade is a 1-mode directed and valued network, while the EU-subsidized R&D collaboration is an affiliation (2-mode) undirected and unvalued network, and the elementary units of this latter are organizations and not countries. Therefore, to the aim to make these two networks comparable, this paper shows and discusses a number of methodological problems and solutions offered to solve them, and provides a multi-faceted comparison in terms of various statistical and topological indicators. A comparative analysis of the two networks structures is made at aggregate and disaggregate level, and it is shown that the common centralization index is definitively inappropriate and misleading when applied to multi-centered networks like these, and especially to the R&D collaboration network. The final conclusion is that the two networks resemble in some important aspects, but differ in some minor traits. In particular, they are both shaped in a core-periphery structure, and in both cases important countries tend to exchange or collaborate more with marginal countries than between themselves.
TopTheoretical Background
It is unlikely that a country is self-sufficient in any industry, because an industry is diversified in many different products, and a country’s industry can hardly produce all of them, no matter how developed or specialized that country is. Moreover, it’s practically impossible that a country can produce all the components and raw materials for a given industry, and in the required amount. International trade theory made these points clear since long (Bowen et al., 2012; Ethier et al., 1995; Feenstra, 2003; Feenstra & Taylor, 2010; Milberg & Winkler, 2013). More recently, evolutionary economic geography (Boschma & Frenken, 2006; Boschma & Lambooy, 1999; Boschma & Martin, 2007; Essletzbichler & Rigby, 2007; Frenken & Boschma, 2007; Martin & Sunley, 2007), and more particularly the theoretical perspectives of global value chain (Gereffi, 1999; Gereffi et al., 2005; Humphrey, 1995; Humphrey & Schmitz, 2002), and of international knowledge networks (Cappellin & Wink, 2009; Gross Stein et al., 2001; Lundan, 2002; Maxwell & Stone, 2007) have underlined that industry’s trade patterns depend not only on trade barriers, transportation costs, labor costs and other traditional variables investigated by international economics. They depend also – and in some cases, like high-tech industries, primarily – on the dynamics of international innovation diffusion, technological trajectories, and the like. Hence, it could be reasonably wondered to what extent, in a given sector, international trade patterns resemble R&D collaboration patterns and, when differ, in which ways they do. In this work we deepen this issue, evidencing conceptual and methodological issues related to this comparison.