規模報酬與最適貿易政策

Production Function and Optimal Trade Policy

楊雅博(Ya-Po Yang) ； 吳世傑(Shih-Jye Wu) ； 黃鴻(Hong Hwang)

《經濟論文》 30卷1期 (2002/03) Pp. 1-27

https://doi.org/10.29628/AEP.200203.0001

摘要

一般探討垂直相關產業之貿易政策的文獻，大都假設生產函數為固定比率(fixed proportion)。此一假設雖然可以使模型大為簡化，但會對結論造成重大影響。實務上，許多產業的生產技術亦非屬固定比率。本文建立一個生產技術函數為變動比率(variable proportion)的上下游模型，假設本國廠商自國外進口中間原料，生產最終財並將此最終財悉數出口至第三國，並藉以分析規模報酬對政府最適貿易政策的影響。本文發現當規模報酬趨小時，政府的最適進口政策會由進口課稅變為進口補貼；政府的最適出口政策亦會由出口課稅變為出口補貼。此外，本文亦比較進口政策與出口政策的福利水準，發現在規模報酬遞增（不變）時，最適進口政策的福利水準高於（等於）最適出口政策的福利水準；若生產函數屬規模報酬遞減，最適進口政策很可能會隨著規模報酬變小轉而優於最適出口政策。

關鍵字

垂直相關產業 ； 進口關稅 ； 出口補貼 ； 貿易政策

並列摘要

When modeling vertically related markets, most literature on trade and industrial organization assume a fixed-coefficient technology. This paper shows that optimal policies may be reversed if the fixed-coefficient technology assumption is relaxed. The model is based on three countries whereby the home country imports an intermediate good from a foreign monopolistic supplier, manufactures the entire final product at home, and then exports it to another foreign market in which it has monopoly power. When the technology is of a Cobb-Douglas type, exhibiting a strong diminishing return to scale, it is shown that the optimal trade policy is one that subsidizes either the import of the intermediate good or the export of the final good. Moreover, the welfare level under the optimal import policy is higher than (equivalent to) that under the optimal export policy when the technology in question exhibits increasing (constant) returns to scale, while the welfare ranking is, in general, reversed, when the returns to scale are diminishing.

並列關鍵字

Vertically related markets ； Returns to scale ； Import tariffs ； Export subsidies

參考文獻

Bernhofen, D. M.(1997).Strategic Trade Policy in a Vertically Related Industry.Review of International Economics.5

Bhagwati, J. N.(1971).Trade, Balance of Payments, and Growth: Papers in International Economics in Honor of Charles P. Kindelberger.Amsterdam:North-Holland.

Brander, J. A.(1981).Intra-Industry Trade in Identical Products.Journal of International Economics.11

Brander, J. A., Krugman, P. R.(1983).A 'Reciprocal Dumping' Model of International Trade.Journal of International Economics.15(3/ 4)

Brander, J. A., Spencer, B. J.(1984).Trade Warfare: Tariffs and Cartels.Journal of International Economics.16