한국의 양자 무역비용이 수출에 미치는 영향: 산업별‧소득수준별 이질효과

A Study on the Effects of Bilateral Trade Costs on Korea’s Exports: Sectoral and Income-Level Heterogeneity

Purpose - This study quantifies how bilateral trade costs shape Korea’s exports and how the effects vary by cost type (tariff vs. non-tariff), sector (manufacturing vs. agriculture), and destination income level. Design/methodology/approach - Using the UN ESCAP-World Bank bilateral trade cost index for 73 partner countries, 2004-2020, we estimate PPML-HDFE gravity models with partner and year fixed effects. Trade-cost variables enter with a one-period lag; interactions identify sectoral and income-group heterogeneity. We report policy-relevant semi-elasticities as percentage changes in exports for a 10% reduction in costs. Findings - Total trade costs significantly depress exports overall and in manufacturing, but not in agriculture. A 10% reduction in total costs raises exports by about 64% to low/lower-middle-income markets, 45.6% to upper-middle-income, and 21.7% to high-income destinations; in manufacturing the corresponding effects are 56.0%, 34.1%, and statistically insignificant for high-income markets. Decompositions show both tariff and non-tariff components are significant for total exports and manufacturing, with non-tariff effects often comparable in magnitude; effects are strongest toward lower-income destinations. Research implications or Originality - By drawing total, tariff, and non-tariff trade-cost measures from a single source within one PPML-HDFE framework, the study reduces measurement mismatch and delivers directly comparable policy elasticities. The results prioritize trade-cost reduction—especially via trade facilitation alongside tariff cuts—in developing markets.