International Trade, Global value chains, Quantitative trade modeling, Development economics.

Publications in refereed journals

Are African exports that weak ? A trade in value-added approach

(The World Economy)Working paper version, Online Appendix

African countries are known to export less than any other group of countries in the world. Many studies have advanced that the main reason for this is the high level of transport costs due to the poor quality of transport infrastructures on the African continent. We first show that, depending on the estimator used, African countries as an aggregate do not necessarily trade a lower volume of gross exports than other countries on average, even though they clearly underperform in exports of final goods. This underperformance, reflected by the greater impact of bilateral trade costs such as distance on African exports of final goods compared to other countries, is not observed for African intermediate goods flows. Second, we formulate a model for trade in value-added by adapting the standard gravity equation to take into account the structure of value-added exports. The proposed model points up the importance of the indirect trade costs of third countries via which a country of origin’s value-added transits before reaching its final destination. When we control for these indirect trade costs in the value-added trade estimation, the additional impact of the bilateral trade costs observed for African countries’ final goods exports is six times lower.

Working papers

Trade in value-added and the welfare gains of international fragmentation (Submitted) 

Job market paper Latest draft, Infer Young Economist Award

It is notorious in the literature that international fragmentation substantially increases the welfare gains of trade which are, as well known, inversely proportional to the shares of domestic trade in intermediates and final goods. Most calculations, however, implicitly assume that a shutdown of trade in intermediate goods would leave the share of domestic trade in final goods fixed, which overestimates the results. The varieties of goods available in a country would likely change if local firms lost access to intermediate inputs required to produce their final goods. The share of domestic trade in final goods should, therefore, vary following a shutdown of international fragmentation. A simple mechanism describes how this share changes following the shock. The shutdown would create a substitution between intermediate goods and final goods imports. The loss of access to foreign intermediate inputs by a country’s local producers would be compensated by an increase in final goods imports using these inputs, which would attenuate the initial impact of the shutdown. Using this mechanism, we calculate that international fragmentation represents on average approximately 20 % of the total welfare gains of trade, while it would represent at least 50 % without this adjustment.

Import substitution revival and the Welfare Gains of International Fragmentation

First draft

This study investigates the welfare effects of a trade shock resulting from a complete shutdown of trade in intermediate inputs. We derive novel insights into the implications of this shock on consumption possibilities. The analysis is conducted within the framework of a model that incorporates endogenous quality and substitution between intermediate inputs and final goods (endogenous technology). We first demonstrate that a shutdown of trade in intermediate inputs does not affect countries' revenues or nominal wages conditionally on the constancy of the share of value added in production. Building upon this insight, we quantify the welfare gains from trade following the shutdown, considering special cases where technology and quality are alternatively endogenous and exogenous, and demonstrate how they relate to welfare formulas already derived in the literature. Our main result shows that the loss of access to foreign intermediate inputs by a country's local producers would increase the price of final goods, but this increase would be partially offset by an increase in imports of final goods that utilize previously imported inputs. Thus, our study emphasizes the significance of considering the substitution between intermediate and final goods when evaluating the consequences of a shutdown of international fragmentation. This research contributes to a deeper understanding of the welfare effects of trade shocks and provides valuable insights for policymakers and stakeholders in assessing the potential consequences of disruptions in global supply chains.

Import processing zones, tools for regional integration ?  The case of the free trade zone of Manaus (Brazil)

Working paper

We examine in this article whether the challenging goal of connecting the isolated Amazonian region of Brazil to the distant economic centre of the country has been accomplished despite its low-quality transport infrastructures and whether the creation of a Free Trade Zone (FTZ) in the region could have played a role in the process. Using a gravity model to assess each Brazilian state's trade performance and level of trade costs, we found that the two entities representing the state of Amazonas which hosts the FTZ were among the most effective intra-national exporters in Brazil in 2008 despite facing the highest level of trade costs in the country. These counter-intuitive findings indicate a potential impact of the FTZ.

Work in progress

The impact of financial constraints on African exports

Draft coming soon

In 2019, according to the World Bank, the domestic credit-to-GDP ratio was 144% for OECD countries, while it was only 44% for Sub-Saharan African countries. Therefore, the latter are facing strict financial constraints that hinder their economic performance in various areas. In particular, these financial constraints impede African enterprises' access to essential equipment necessary to improve the quality and competitiveness of their products, as well as their overall access to advanced economies' markets due to high entry costs. These financial constraints have the potential to limit the export performance of Sub-Saharan African countries, especially when it comes to final goods. Indeed, these goods require additional investments in terms of packaging and marketing, for example. In this article, I demonstrate that African countries export significantly fewer final goods compared to intermediate goods, relative to other countries, and that their financial constraints explain at least 50% of the difference in export performance compared to other countries. It follows that improving access to credit in African countries could significantly enhance their trade performance. 

Product-based cultural change, Migration and Trade joint with  N. Touré

Draft coming soon