Considerable efforts have been made in recent years to produce detailed topologies of the Internet. Although Internet topology data have been brought to the attention of a wide and somewhat diverse audience of scholars, so far they have been overlooked by economists. In this paper, we suggest that such data could be effectively treated as a proxy to characterize the size of the "digital economy" at country level and outsourcing: thus, we analyse the topological structure of the network of trade in digital services (trade in bits) and compare it with that of the more traditional flow of manufactured goods across countries. To perform meaningful comparisons across networks with different characteristics, we define a stochastic benchmark for the number of connections among each country-pair, based on hypergeometric distribution. Original data are thus filtered by means of different thresholds, so that we only focus on the strongest links, i.e., statistically significant links. We find that trade in bits displays a sparser and less hierarchical network structure, which is more similar to trade in high-skill manufactured goods than total trade. Lastly, distance plays a more prominent role in shaping the network of international trade in physical goods than trade in digital services.
Diversification of global food trade partners increased inequalities in the exposure to shock risks
Institute for Biocomputation and Physics of Complex Systems (BIFI), University of Zaragoza, Spain（萨拉戈萨大学复杂系统生物计算与物理研究所）；Department of Theoretical Physics, University of Zaragoza, Spain（萨拉戈萨大学理论物理系）；Sustainability Research Institute, School of Earth, Environment and Sustainability, University of Leeds, UK（利兹大学地球、环境与可持续发展学院可持续发展研究所）
Queen Mary University of London（伦敦大学皇家玛丽学院）；Università di Siena（锡耶纳大学）；Sorbonne Université, Paris Brain Institute (ICM), CNRS UMR7225, INRIA Paris, INSERM U1127, Hôpital de la Pitié-Salpêtrière, AP-HP（索邦大学，巴黎脑研究所（ICM），CNRS UMR7225，INRIA巴黎，INSERM U1127，皮蒂埃-萨尔佩特里埃尔医院，AP-HP）；Dipartimento di Fisica ed Astronomia, Università di Catania, and INFN Catania（卡塔尼亚大学物理与天文系及INFN卡塔尼亚分部）；Complexity Science Hub Vienna（维也纳复杂性科学中心）
