This paper contributes to the existing empirical investigation of Japan-Korea international trade by providing new evidence of intraindustry trade between Korea and Japanese sub-regions. Taking advantage of a Japanese international trade dataset disaggregated by sub-regions, we calculate the Grubel-Lloyd intra-industry trade index for 41 regions of Japan with respect to Korea for the period between 1988 and 2006. By restricting the flows of intra-industry trade to sub-regions, the Grubel-Lloyd index is more likely to capture the effect of the fragmentation of production than the traditional index, which is based on the national level. By using the Japanese prefecture international trade data, it is revealed that intra-industry trade is still pervasive even when it is restricted to trade flows between prefectures and Korea. In intra-industry trade regression models, we introduce extensive and intensive margins of prefecture exports as new explanatory variables. We find that a rise in intra-industry trade is driven by the introduction of a new variety of exports, while intra-industry trade is discouraged by an increase in the trade value of products already exported.

Executive Summary

I. Introduction

II. The Measurement of Intra-Industry Trade and Export Variety
1. Grubel-Lloyd Index for Intra-Industry Trade
2. Hummels-Klenow Indices for Export Margins

III. Overview of International Trade of Japan with Korea in the Last Twenty Years
1. Exports and Imports
2. Japanese FDI into Korea
3. Intra-Industry Trade Between Japan and Korea

IV. Disaggregation of Japan-Korea Trade by Sub-regions
1. Prefecture Intra-Industry Trade
2. Prefecture Extensive Margins and Intensive Margins

V. A Deepening of Existing Trade or a Growth in Variety?
1. The Traditional Determinants of IIT
2. Extensive Margin and Intensive Margin on IIT
3. The Transformation of the IIT Index
4. The Data
5. The Empirical Results

VI. Discussion and Conclusion

References