The export price index with the effect of variety and an empirical analysis

The standard international trade models predict that economic growth induces decreasing export prices. Korea has recorded sustainable economic and export growth, and its export prices have been deteriorating over the last decades. Unlike the standard assumption of one good per country, the new theoretical approach by Krugman Krugman, P. (1980) ‘Scale Economies, Product Differentiation, and Pattern of Trade’. American Economic Review 70, 950–959, Krugman, P. (1989) ‘Differences in income elasticities and trends in real exchange rates’. European Economic Review, 33, 1055–1085.], and Helpman and Krugman Helpman, E. and Krugman, P. (1985), Market structure and foreign trade: increasing returns, imperfect competition, and international economy, The MIT Press, Cambridge, MA.] takes into account varieties of goods produced in each country. And many studies suggest that traditional estimates without variety effect have been rather under-stated. Therefore this paper develops a proper modeling for quantifying the impact of export variety on an exact export price index. Throughout the period (1984–2000), the conventional export price index without variety effect leads to under-state Korea's export price by 89.3%. This paper shows that the fall in Korean export prices has been offset by the effect of export variety. This paper emphasizes the effect of export variety on international trade.