Abstract. Global value chains (GVCs) emerged as the paradigm for the international organization of production. For most goods and services production is nowadays vertically fragmented across different countries and this reality gave rise to a significant new strand of research in international trade. This article starts by discussing the major driving forces of GVCs in recent decades. Next, it surveys the main measures of GVCs, accounting for their different scopes and required data sets. The article highlights the timing of the contributions to the literature, signalling their sequential nature and the trend toward more accurate and data-demanding indicators.

This paper investigates a specific aspect of international production linkages that, following Hummels et al. (2001), is commonly designated as vertical specialization (VS) -the use of imported inputs to produce goods that are afterwards exported. We propose a relative measure of VS-based trade that combines information from Input-Output matrices and international trade data, producing results for a large sample of individual countries and geographical areas with a detailed product breakdown over the 1967-2005 period. This measure identifies a country's trade flow as associated with VS activities when the share of exports of a good relatively to the world average is above a given threshold and it is accompanied by a relative share of imports of a related intermediate product that is also above the threshold. The quantification of VS-based trade for each country/product pair in each period is made in a relative and conservative manner, since it includes only the value of intermediate imports that surpasses what is implied by the chosen international threshold. The detailed results can be subsequently added up to get any product or geographical breakdown desired. We illustrate this measure by showing the evolution of VS activities at the world level over the last four decades using a product breakdown by technological intensity and a geographical breakdown by main areas. The results point to a substantial increase of VS in high-technology products over the last two decades. There is also empirical evidence on the sharp increase of VS activities in East Asia.

Expansion into foreign markets is a major decision for a firm and it involves choices about which countries to approach and which products to export. We use a new database that covers the universe of export transactions for firms located in Portugal for the period 1996-2005 in order to examine the joint decision of where and what to export. We find that multi-product and multi-destination firms are crucial in explaining the dynamics of export over time. The exporters' portfolio is very diversified in terms of sectors and product tenure and it is frequently modified over time. We show that, while continuing firms exporting continuing products to continuing destinations are fundamental in explaining the year-to-year growth rate of aggregate exports, the contribution of gross entry and exit of both destinations and products is, in absolute value, as important as the contribution of gross entry and exit of firms. Moreover, growth dynamics of new exporters proceeds along lines that are different from those characterizing the representative incumbent firm. The destination extensive margin is almost as important as the destination intensive margin and almost one-third of the latter is due to product switching (the product extensive margin). Firms access new destinations mostly by exporting new products, i.e. products that were not previously sold anywhere else by the firm. Products already exported by the firm to other destinations are an important but not the primary way to enter new destinations.

Standard-Nutzungsbedingungen:Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch gespeichert und kopiert werden.Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich machen, vertreiben oder anderweitig nutzen.Sofern die Verfasser die Dokumente unter Open-Content-Lizenzen (insbesondere CC-Lizenzen) zur Verfügung gestellt haben sollten, gelten abweichend von diesen Nutzungsbedingungen die in der dort genannten Lizenz gewährten Nutzungsrechte. Global Value Chains (GVCs) became the paradigm for the production of most goods and services around the world. Hence, interconnections among countries can no longer be adequately assessed through standard bilateral gross trade flows and new methods of analysis are needed. In this paper, we compute measures of network analysis and apply visualisation tools to value added trade flows in order to understand the nature and dynamics of GVCs. The paper uses data on the bilateral foreign value added in exports for the period 1995-2011 and, in each year, GVCs are represented as directed networks of nodes (countries) and edges (value added flows). The analysis is extended beyond total trade flows to discuss the distinct roles of goods and services in GVCs. Moreover, the differences between Germany, the US, China and Russia as major suppliers of value added in GVCs are also examined. Terms of use: Documents in Non-technical summaryIn recent decades, the rise of Global Value Chains (GVCs) has dramatically changed the organisation of world production of goods and services, making a deep and lasting impact on international trade and investment patterns, as well as on labour and product markets.As GVCs spread worldwide, the concept of "country of origin" becomes increasingly difficult to apply, because a country may stand as a large exporter of a specific good without adding much value to it. Hence, the analysis of gross trade flows has to be complemented with the analysis of trade in value added, tracking down the original source country of the value added. Even if GVCs are a complex phenomenon, it is essential that policy-analysis takes on board their impacts on the quantification and interpretation of traditional trade and competitiveness indicators and on the forecasting of macroeconomic developments.The expansion of GVCs has also strongly increased the economic interdependence between countries. In this context, since exports increasingly embody a sizeable share of foreign value added, important questions about the interconnections among countries arise, notably in relation to the impact and propagation of economic shocks. For example, the significant role of specific countries in the functioning of GVCs poses questions regarding the resilience of the world trade system if they are hit by large shocks. All these aspects have a bearing on monetary policy decisions.The measurement of trade in value added, breaking down gross trade flows along sources and destinatio...