關稅의 理論的 考察 = The Theoretical Study of Tariff

다국어 초록 (Multilingual Abstract)

In the course of the past fourty years prevailing opinion among economists regarding the influence of commercial policy on economic development has changed radically. The classical advocacy of free trade evolved out of Adam Smith's attack on Mercantilism. On the theoretical side it rested not only the static theory of comparative advantage, but on a broader sociological recognition of the beneficial effects of exposure to foreign competion in generating the urge for social change and economic improvement.
Besides the classical advocacy of free trade, some economists has advocated protection as a means of promoting the economic development of the relatively backward regiongs. Among the various means of protection tariff has recognized as the most important one. Tariff on final goods protects home production, that is to say it increases the final output or real income above what it otherwise would be, and decreases the import.
The imposition of tariff has seven effects. They are 1) the protective effect 2) the consumption effect 3) the revenue effect 4) the redistribution effect 5) the terms-of-trade effect 6) the employment effect 7) the balance of payment effect. The size of the protective effect, relative to agiven tariff, is evidently determineded by the elasticity of supply curve. If the supply curve in highly elastic, the protective effect will be large; if inelastic, small.
In figure 1 the elasticity of supply curve (Es) is represented by the change ratio of price, Hence,
Es=QQ_1/OQ÷PP'/OP=QQ_1/OQ×OP/PP' ……(1) OP'=(1+t)OP
where t= rate of tariff, accordingly OP/PP'=1/t ……(2)
subsitud (2) in (1) then QQ_1(Protective effect) depends upon the elasticity of supply curve.
If a country has a fair idea of the demand and supply curves involved in a partivular commodity, and if these are not particularly inelastic, there is little difference whether it imposes a tariff or a quota. If the quota is set at the volume of imports which would result from the imposition of a given tariff, the protective effect will be the same in either case, and so will the consumption and the redistribution effects. But there is a distinction between the effects of tariffs and of quotas. To change a tariff into a quota, even without reducing the existing volume of imports, may convert a potentcel domestic monopoly into a actual one. In Figure 6, the AR curve is displaced to the left by the amount of quota, TW. and a nwe marginal revenue curve, MR', drawn to the displaced curve, AR'. Both AR' and MR' have an independent existence until the former gets to the world price plus tariff(OP'). This then becomes the average revenue curve and the marignal-revenue curve until the old average revenue curve is reached, where the marginal-revenue curve returns to its original course. This volume of domestic production plus the import quota, TW, will produce a price of OP'', which is above the old world price plus tariff, OP'.
Concerning the argument between tariffs and subsidies, it may be summarized as follows; (1) the subsidy is more efficient than the tariff in securing an increase in domestic production, (2) the tariff is more efficient than the subsidy in securing a reduction in imports. In Figure 8, under free trade, domestic production would be OQ1, total consumption OQ5, and imports Q1Q2. To increase domestic output to the level OQ2, an excess production cost measured by the area A must be inqurred; this result could be securred by the granting of a subsidy on domestic production at the rate t. If instead a tariff were imposed at the same effect would be securred, but in addition to the excess production cost A the country would incure a consumption cost measured by the area B. Thus the subsidy is more efficient than the tariff in securing an increase in domestic production. Now consider the situation with the tariff in securing an increase in domestic production. Now consider the situation with the tariff in effect; imports are reduced from Q1Q5 under free trade to Q2Q4 under the tariff, at a cost in real income foregone of A+B. The same reduction of imports could be obtained by a production subsidy at the rate S sufficient to increase domestic output to OQ3, where Q2Q3=Q4Q5, the cost in real income foregone in this case is A+C+D, since Q2Q3=Q4Q5, C is necessarily greater than B and A+C+D greater than A+B, The tariff is therefore more efficient than the subsidy in securing a reduction in imports.
Supposing that a country is determinded to increase the output of a group of industries above what it would be under free trade, and has to choose protection as its means of achieving this aims. The question then arise, what tariff structure should it employ for this purpose? The answer to this question defines the second-best optimum tariff structure. The usal drescriptionof economists faced with this question is that the rate of duty should be the same for every item protected This logic is illustrated in the accompanying diagram(Figure 9 and 10)
Finally the formula for the ooptimum welfare tariff is derived as follows. The optimum welfare tariff is equal to the elasticity of the foreign reciprocal demand for exports, reduced by unity (t=E_(frd)-1) This is a basic formula, from which others can be deduced. The elasticity of reciprocal demand can be expressed in terms of the elasticity of demand curves and the result substituted in the optimum tariff formula. The reciprocal demand curve is a functional relationship of the form Y=F(X). The demand curve derived from it is of the form X=f(X/Y) and its elasticity
e_(fd)=E_(frd)/E_(frd)-1, where E_(frd)=e_(fd)/e_(fd)-1 and t=1/e_(fd)-1
That is, the optimum tariff rate is equal to the reciprocal of one less than the foreign elasticity of emand for exports as a function of the barter terms of trade.

목차 (Table of Contents)

• Ⅰ. 序 言
• Ⅱ. 關稅의 效果
• 1. 保護效果
• 2. 交易條件效果
• Ⅲ. 關稅와 割當制및 補助金制
• 1. 割當制
• 2. 補助金制
• Ⅳ. 最適關稅
• 1. 準最適關稅
• 2. 最適關稅
• Ⅴ. 結 言