比較利益、異質生產者與內生彈性

COMPARATIVE ADVANTAGE, HETEROGENEOUS FIRMS AND ENDOGENOUS ELASTICITY

徐則謙(Tsechien Hsu)

《經濟論文》 47卷1期 (2019/03) Pp. 125-162

摘要

結合Heckscher-Ohlin與Melitz（2003）的模型特性，Bernard et al.（2007）（BRS）指出，在僅有部份生產者出口的前提下，貿易自由化透過要素的重新分配，會改變產業間之相對生產力，進而放大稟賦差異所產生的比較利益，BRS將之稱為放大效果（magnification effect）。然而實證上研究比較利益如何隨時間改變的文獻，有些呈現各國間比較利益逐漸放大，有些呈現逐漸縮小的結果。本文指出，若考量競爭對加價的影響，當兩產業之要素密集度差異低於一門檻值時，此放大效果隨貿易自由化非單調（non-monotonically）地變動，反之則單調（monotonic）地變動。數值例子顯示，若是非單調地變動，在自由化程度較低時，進一步自由化強化放大效果，但在程度較高時，該效果隨自由化減弱，並在市場完全融合後消失；反之則放大效果隨自由化逐漸下降並消失。此結果呼應實證發現分歧的現象。雖然BRS亦隱含放大效果之減弱，但此結果伴隨所有生產者出口以及絕對生產力逐漸下降至封閉水準，不符過往實證之發現，因此作者並未加以討論。本模型可在產生非單調關係的同時，在此兩點上滿足過去實證的結果。

關鍵字

異質生產者 ； 內生加價 ； 產業平均生產力 ； 比較利益 ； 產業內貿易 ； Heckscher-Ohlin模型

並列摘要

Bernard et al. (2007) (BRS) combine the Heckscher-Ohlin model and the mechanism of Melitz (2003) to show that if not all firms export, trade changes relative industrial productivity and magnifies the Heckscher-Ohlin comparative advantage through factor reallocation. This paper shows that depending on the difference in factor intensity between industries, the magnification effect changes monotonically or non-monotonically with trade liberalization when the mechanism comes from the increase in markup. BRS also mention the possibility of non-monotonicity. However, the decrease in magnification effect accompanies the decrease in industrial productivity and the result that all firms export, which does not coincide with empirical findings. In this paper, the non-monotonicity is not based on firms' export decision, and industrial productivity increases during trade liberalization. The ambiguous relationship between liberalization and comparative advantage also coincides with the recent empirical findings.

並列關鍵字

Heterogeneous firms ； Endogenous markup ； Industrial average productivity ； Comparative advantage ； Intra-industry trade ； Heckscher-Ohlin model

參考文獻

Arkolakis, C., A. Costinot, and A. Rodriguez-Clare (2010), “Gains from Trade under Monopolistic Competition: A Simple Example with Translog Expenditure Functions and Pareto Distributions of Firm-Level Productivity,” Mimeo, Yale University.

Aw, B. Y., S. Chung, and M. J. Roberts (2000), “Productivity and Turnover in the Export Market: Micro-Level Evidence from the Republic of Korea and Taiwan (China),” World Bank Economic Review, 14, 65–90.

Badinger, H. (2007), “Has the EU’s Single Market Programme Fostered Competition? Testing for a Decrease in Mark-Up Ratios in EU Industries,” Oxford Bulletin of Economics and Statistics, 69, 497–519.

Bellone, F., P. Musso, L. Nesta, and F. Warzynski (2014), “Productivity, Trade and Endogenous Mark-Ups: Testing Some Micro-Level Implications of the Melitz-Ottaviano Model,” Mimeo, University of Nice Sophia Antipolis.

Bernard, A. B. and J. B. Jensen (1999), “Exceptional Exporter Performance: Cause, Effect, or Both?” Journal of International Economics, 47, 1–25.