2013年-世界发展银行全球_Wage_Effects_of_High-Skilled_Migration___International_Evidence_23页_207kb

Summary of "Wage Effects of High-Skilled Migration: International Evidence"

Core Content

This paper investigates the wage effects of high-skilled migration between countries, focusing on how migration impacts the relative wages of skilled workers in destination and source economies. It also explores the broader productivity and economic implications of such migration, including changes in GDP per capita and total factor productivity (TFP).

Main Views and Key Findings

1. Theoretical Framework

• The migration of high-skilled workers can have productivity effects at the macro level, leading to:
  • Wage increases for skilled workers in the host country.
  • Wage decreases for skilled workers in the source country.
• The paper develops a theoretical model to analyze how migration affects TFP and wage levels, considering:
  • Learning spillovers and human capital externalities.
  • Endogeneity issues arising from wage differences influencing migration decisions.
• The model predicts that:
  • An increase in high-skilled emigration raises relative TFP in the destination country.
  • The effect on relative skilled wages is ambiguous unless TFP effects are strong.

2. Empirical Analysis

• The study uses bilateral migration data to examine the effects of skilled migration on:
  • Log differences in GDP per capita.
  • TFP.
  • Wage income of skilled workers.
• To address endogeneity, the authors propose instrumentation strategies, including:
  • Using past migration stocks as instruments.
  • Controlling for lagged low-skilled migration rates.
• The empirical model is specified as:
  $$
  \log \left(\frac{y_{j,t}}{y_{i,t}}\right) = \beta_0 + \beta_1 SMig_{ij,t} + \beta_2 UMig_{ij,t-1} + x_{ij,t-1}'\beta_x + u_{ij}
  $$
  where:
  • $SMig_{ij,t}$ is the high-skilled emigration rate from country $i$ to $j$.
  • $UMig_{ij,t-1}$ is the lagged low-skilled emigration rate.
  • $x_{ij,t-1}$ includes other controls such as relative school enrollment rates, investment rates, and urban population shares.

3. Key Results

• The paper finds that:
  • High-skilled migration is associated with positive wage effects in the destination country.
  • Negative wage effects in the source country.
  • Relative TFP increases in the destination due to the presence of more skilled workers.
  • Complementarity between high- and low-skilled labor implies that an increase in low-skilled migration can also benefit high-skilled workers in the destination.
• The external productivity effects of skilled migration are likely to dominate over internal effects, suggesting a net positive impact on destination countries.

4. Robustness and Policy Implications

• The authors conduct robustness checks using different wage measures (e.g., assuming that high-skilled workers earn the median wage abroad).
• The results support the "brain gain" hypothesis, where the destination country gains more from skilled migration than the source country.
• The findings are consistent with previous studies on single-country wage effects of high-skilled immigration, such as those by Borjas (2003), Dustmann, Fabbri, and Preston (2005), and Friedberg (2001).

Conclusion

The paper concludes that the wage effects of high-skilled migration are not uniform across countries and are influenced by productivity externalities and migration patterns. It emphasizes that destination countries generally benefit more from skilled immigration than source countries, and that the net effect on wages is positive in the destination and negative in the source. The study provides international evidence for the theoretical possibility of positive wage effects in host countries and underscores the importance of instrumental variables in addressing endogeneity concerns.