有关移民涌入对接收移民国家影响的实证研究：一项调查

This paper provides a survey of empirical studies that examine the impact of immigration inflows on host-country economies. We first discuss existing studies analyzing how immigration affects labor-market outcomes such as wages, employment, and unemployment rates. Although an increase in labor supply due to immigration may, in the short run, put downward pressure on wages and raise unemployment, this article documents that existing empirical results do not necessarily support the theoretical result. We also review studies that highlight the mechanism of “task specialization,” in which native workers adjust their occupations in response to immigration by moving into tasks where they hold a comparative advantage, thereby limiting wage declines. In addition, we discuss existing studies investigating the effects of immigration on internal migration and human capital accumulation. The discussion covers both research focusing on Japan and other countries. Finally, we summarize the shift–share instrumental variable approach and outline its methodological challenges.