2012年-世界发展银行全球_Economic_Geography_and_Economic_Development_in_Sub-Saharan_Africa_43页_541kb

Summary of "Economic Geography and Economic Development in Sub-Saharan Africa"

Core Content

This paper by Maarten Bosker and Harry Garretsen investigates the role of market access in explaining economic development in Sub-Saharan Africa (SSA) over the period 1993–2009. It builds on the New Economic Geography (NEG) theory, which emphasizes the importance of a country's relative geography in determining its access to international markets and, consequently, its economic performance.

Main Points

• Geography and Economic Performance: SSA's poor economic performance is often attributed to its physical geography, but the paper argues that relative geography—a country's position in the global system of trade—is also a critical factor.

• Market Access and Economic Development: The paper finds that market access has a robust and positive effect on GDP per worker in SSA countries. This effect has increased in importance over the last decade.

• Importance of Regional Market Access: The study reveals that access to other SSA markets is particularly significant in explaining economic development within the region. Access to markets in the rest of the world (ROW) is less impactful, even after controlling for other factors.

• Empirical Strategy: The authors follow the method introduced by Redding and Venables (2004), which uses bilateral trade data to estimate market access. They construct yearly measures of market access by analyzing manufacturing trade flows, and then use these measures to estimate the impact on economic development.

• Trade Equation and Market Access: The trade equation used is:

  $$
  \ln EX_{ijt} = \rho_{it} + \mu_{jt} + \beta \ln T_{ijt} + \varepsilon_{ijt}
  $$

  This equation captures the relationship between bilateral exports, trade costs, and market capacities.

• Trade Cost Specification: Trade costs are modeled as a multiplicative function of the following variables:

  • Bilateral distance
  • Common border
  • Common language
  • Common colonial heritage (common colonizer and colony-colonizer relationship)
  • Membership in the same African regional trade agreement

• Handling Zero Trade Flows: The paper addresses the issue of zero trade flows using a Heckman two-step estimation method, which accounts for endogenous sample selection. This approach avoids biases that could arise from simply ignoring zero observations.

• Key Findings:

  • Market access has a significant positive effect on economic development in SSA.
  • The effect of market access for manufactures is stronger in the second half of the sample period (2000–2009).
  • Access to other SSA markets is more crucial than access to ROW markets for economic development in the region.
  • The paper suggests that improving infrastructure, reducing the burden of landlocked countries, and increasing regional integration can positively affect market access and economic development in SSA.

Key Information

• Data Sources: The study uses UN COMTRADE data on bilateral manufacturing exports between SSA countries and other nations.

• Methodology: The authors construct yearly measures of market access using gravity model-based trade equations and panel data methods to control for time-invariant unobserved heterogeneity.

• Policy Implications: The paper highlights the importance of policy interventions aimed at improving market access for SSA countries, including:

  • Infrastructure development
  • Regional economic integration
  • Preferential access to European and U.S. markets

• Limitations and Considerations:

  • The study focuses on manufacturing exports, as they are more closely aligned with NEG theory.
  • Natural resource exports are excluded from the analysis due to their dominance in SSA trade and the lack of theoretical support for their role in economic development.
  • The effect of market access in SSA is lower than in other regions like Brazil, Indonesia, or China, but it has increased over time.

Conclusion

The paper concludes that economic geography, particularly market access, plays a significant role in shaping economic development in SSA. It emphasizes the importance of regional trade and market integration for the region's future economic growth. The findings support the idea that improving market access through policy reforms could be a vital tool for enhancing SSA's economic performance.