Trade liberalization and wage inequality: Evidence from Korea

This paper investigates the heterogeneous income distribution effects of trade liberalization using Korean survey data from years of 2000–2015. Following the Stolper-Samuelson theorem most of previous research studying the effects of trade liberalization on wage differences focus on workers’ characteristics (e.g., skilled or unskilled) while heterogeneity within the same worker group has not been yet substantially investigated. To fill this gap, this paper provides empirical evidence of wage inequality across firms within the same group of workers caused by trade liberalization, potentially implied in the new-new trade models with firm heterogeneity. Employing a difference-in-differences (DID) specification, we find that the wages of unskilled workers in Korea have increased since its FTAs with more advanced countries, such as members of EU and the US, came into effect, while the effects on the wages of skilled workers are negative but not statistically significant. We also show that wage effects are heterogeneous across firms within unskilled and skilled worker groups, while the positive effects are statistically significant and largest for unskilled workers in medium-large sized firms. These findings are in line with both traditional and new-new trade models.