出口结构对出口的影响【外文翻译】.doc

本科毕业论文外文翻译原 文：THE IMPACT OF THE COMPOSITION OF EXPORTS ON EXPORTPERFORMANCE出 处： DE ECONOMIST 135, NR. 2, 1987 作 者： S. BRAKMAN AND C.J. JEPMA 1 .INTRODUCTION The issue of what determines countries export share in international trade has often been the subject of empirical analysis. Often such an analysis is carried out by using simple single-equation models focusing on substitution of demand. Common practice thereby is to concentrate on the calculation of the elasticity of substitution between two exporters (usually the country concerned and a group of competitors) in a third market, simply by taking the quotient of the export demand equations for the two exporters. In such a framework competitiveness is crucially linked with relative prices.Reality, however, is far more complicated. The single-equation models therefore have been subject to severe criticism for their simplicity and the a priori assumptions which have to be made. Most criticisms were of an econometric nature (starting from Orcutt, 1950); however, theoretical doubts have been expressed as well. This resulted in some extensions of the model, e.g. the introduction of supply factors, the incorporation of non-price factors, and the impact of the business cycle. A general weakness of the traditional trade models is still lack of attention to the impact of the differences in the composition of the exports between competing countries on their relative export performance. Nevertheless Tyszynski (1951) did separate the impact of the composition of exports and competitiveness on export performance; others followed, but the precise relationship between the composition of exports and competitiveness remained unclear. The major contribution to this issue has been made by Ooms (1967), but received little attention. Also hardly any attention has been given to the policy implications of the models.The present paper tries to indicate how the composition of exports is related to export performance, both directly and via the (other) factors determining the exports, and can be considered an extension of the Ooms model in some respects with an emphasis on the policy aspects. A set of trade models is presented. They differ with respect to the underlying assumptions, but generally have in common that two regions of destination are distinguished, enabling analysis of the impact of the (regional) composition of the exports on the relative export performance.2 .THE BASIC MODEL To illustrate the impact of differences in the composition of the exports on relative export performance of countries, we will start from the simple well-known substitution-of-demand model. Since the application of this model is often discussed with relation to the balance of payments, the dependent variables in the model will have a value dimension. The basic structure of the model therefore is:（q1p1/q2q2）j=fi(p1/p2) （2）where Plj(P2j) = the price of the commodity supplied by 1 (2) to market j, ql; (qzj) = the international demand from a particular market j for the commodity supplied by 1(2). The two importers will be indicated as I and II. ql(q2) represents the total volume of the exports of 1 (2). The main distinction from the usual substitution-of-demand approach is in the introduction of different markets of destination, which allows for dealing with the influence of the composition of exports on relative export performance. For explanatory reasons only two markets of destination will be distinguished; generalizations can easily be made.If it is assumed that both prices do not change, supply elasticities are infinite, suppliers do not apply price discrimination, and if also the usual assumptions with regard to income and price elasticities are made (see for example Learner and Stern, 1970, p. 60), then it follows after some manipulations that :(q1P1)-(q2p2)=(q1ip1/q1p1-q2Ip2/q2p2)MI+（q1IIp1/q1p1-q2IIp2/q2p2）MII （2）M1 and MII represent the value of import demand of the respective countries of destination; it should be noted that the two suppliers are different from the two countries of destination. A indicates the growth rate of a variable.(2) indicates that an increase in the exports of a country will be larger (smaller) than that of the other country, if the share of exports of that country going to I is larger (smaller) than that of the other countrys exports, and if at the same time the increase in Is imports is larger (smaller) than the increase in IIs imports. In other words, the only factor determining the difference in export success between both suppliers is the regional distribution of their exports.3.1 Specific Regional Preferences Until now no attention has been given to the impact of differences in the regional preferences of the importers. It has been assumed that an increase in the value of the imports of a particular market with a specific percentage will lead to the same increase in import demand in all directions. In reality, countries have particular regional preferences, due to, among other things, former colonial relations, cultural and political ties, similar languages, etc. These preferences may cause changes in import demand to differ between different suppliers of competing goods. At the product level these special preferences can be the result of differences in style, fashion, delivery conditions, etc. These factors are the more relevant, if, in empirical applications of the model, the commodity in the model actually consists of a commodity bundle which may be typical for the exporter under consideration. Therefore, it seems realistic to allow for differences in import elasticities betweenimporters (assuming a constant relationship between imports and the abovementioned variables).Another criticism is that supply elasticities are assumed to be infinite. Thisassumes constant returns to scale and the ability of the exporter to expand his supply according to the international demand for its products. Several factors may cause this assumption to be unrealistic. First, the supply of individual exporters is usually small compared with total demand at the international market, so the capacity to expand the output without increasing the marginal costs will be limited. Second, empirical results (Gregory, 1971) indicate that even if export prices virtually stay the same during a business cycle - conform- able with expectations if constant returns to scale are present - non-price factors such as delivery times, guarantee conditions, etc. may substantially have changed, indicating decreasing returns to scale.Both criticisms can be dealt with by extending the model with income elasticities of importers which vary across suppliers, and by explicitly introducing the supply side. By doing so the export prices and the trade flows are determined simultaneously.The former observation, again, can be important from a policy point of view, because it illustrates that even if the composition of the exports of a particular country and the relative prices of its exports do not threaten its relative export performance, yet its market share can decline due to the fact that the importers for several reasons (see above) do not expand their demand proportionally in all directions. Further, the result illustrates that one might distinguish between two kinds of competitiveness: price competitiveness and what one might call non-price competitiveness. The latter form of competitiveness aims at changes in the special preferences of importers.3.2 The Influence of the Supply Side on Export Performance The question now arises what the implications are for the development of market shares when supply factors are incorporated into the model so that prices and trade flows can be determined simultaneously. To answer this question, it is supposed that the quantities supplied by country 1 and 2, q1s and q2s, are an increasing function of: a) the export prices of their respective products, Pl and P2, relative to the prices that can be received if the products are sold in the home market, bl and b2 respectively; b) the capacity available for the exports to I, G.c) the capacity available for the exports to II, CH.The distinction between b and c has been made to express the possibility that any change in the export capacity of a supplier may give rise to a change in supply biased towards any of the countries of destination. The ratio behind this could be that differences in size of markets of destination may lead to a situation in which, for instance due to scale factors, the regional distribution of a marginal increase in the exports of a particular exporter deviates from the average distribution.4. ILLUSTRATIONS To illustrate what the implications of the different models are for policy measures with respect to relative export performance, some examples will be given. The goal is to demonstrate that a too narrow perception of the factors which determine relative export performance may lead to biased and possibly wrong policy measures. The models described in the former section will be classified in the following as models a to f.Model a is described by (1). In this model the composition of exports is not dealt with in any way; the size of export flows are assumed to be determined by demand factors only, and they are only a function of relative export prices. This model specification is not only usually applied in the standard illustration of subsitution-of-demand models in textbooks (cf. Leamer and Stern, 1970); also numerous estimates have been carried out to assess the values of demand lasticities in international trade having basically the concept of this model in mind. Model b is described by (2). This model differs from model a because here attention is given to the impact of the composition of exports on relative export performance. In the specification, for the sake of convenience, only the regional distribution of the exports is dealt with. The model could be expanded, however, by also dealing with the impact of its commodity composition (see also he following). In contrast with the former model, the assumption has been made that relative prices do not change and therefore have no impact on the changes in the market shares. This is in agreement with the well-known law of one price which is often believed to hold for countries exporting mainly commodities, the prices of which are determined on the world market.Model c is described by (3). Here the assumption is made that both the com-position of exports and the relative prices matter. This conforms with the starting point of the well-known constant-market-shares analysis, according to which the change in a countrys exports can be broken down into parts which can be attributed to the (given) composition of a countrys exports and a residue (usually also comprising the second-order effect) which represents the impact of relative competitiveness. The flows (again) are determined by demand factors only.Model d is described by (13). In contrast with model c, model d recognizes that an importer may have different preferences with respect to the goods offered by suppliers from different countries. This is particularly plausible if the commodities in the model have the character of a commodity bundle. However, all kinds of noneconomic factors also can bias the preferences in bilateral trade. An important limitation of the former models is that no attention has been given to the commodity dimension of the trade flows. In reality the commodity composition of exports can differ widely between exporting countries, and, according to the results of several decomposition analyses, may be expected to have an impact on relative export performance as well. Therefore, the application of the former models has been repeated by using data for two commodity groups: agricultural and industrial commodities respectively (SITC 0 + 1, and 5-9). The results are determined as the weighted averages for both categories of commodities, using trade shares as weights. The latter is based on an assumption which more or less coincides with the well-known Armington assumption made in international trade modelling, namely that an importer first takes a decision on the commodity composition of its imports, and only thereafter and independently from the former decision, decides on the regional distribution of imports.5. CONCLUSION With the help of a set of different trade models using two suppliers and two regions of destination it is shown that the composition of the exports not only directly influences the relative performance of the total exports, but may also indirectly have a strong influence. The reason is that the composition of exports also influences the sensitivity of total exports for changes in the variables which determine and exporters competitiveness. Therefore, the composition of exports will constitute an integral part of competitiveness. An implication is that if in an analysis of export performance no attention is given to this phenomenon, the results may be severely biased leading to the wrong policy conclusions with respect to the possible success or failure of (general) price policies such as exchange rate policies. A simple application with export data of France and Germany towards the USA and Japan and the relevant elasticities derived from the literature served to illustrate the case. 译 文：出口结构对出口的影响一、 简介实证分析的主题往往是国家的出口份额是由什么决定的。经常进行这样的分析使用简单的模型去替代集中的命令。常用的方法是两个出口国通过简单的出口需求方程集中的计算替代两个出口国在第三市场中的份额。在这样一个框架中竞争力与至关重要地相对价格联系在一起。然而，实际上更为复杂。单方程模型是因为他们简单的和必须要做的假设已经受到严厉的批评。大多数的批评是针对计量经济学性质，然而对理论也已经表示了怀疑。这也导致了模型的扩张问题例如:引进的供给因素，非价格因素和商业周期。对传统贸易模式仍然缺乏重视，表现在对他们的国家出口结构的相对竞争表现。然而Tyszynski把他们表是成影响出口的组成和竞争力的出口业绩，其他的是次要，但是出口和竞争力两者之间的确切关系仍不确定。对这个问题Ooms模型已经取得了重大贡献，但很少受到关注，所以模型的含义也几乎没有得到重视。本文试图说明出口业绩和出口组成有关，包括直接的和间接的出口因素，并且可以被认为是Ooms模型的扩充部分尤其是政策方面。一套贸易模型被提出，他们的基本假设方面不同，但是一般有共同的目标使他们分析地区的出口组成因素的表现。二、 基本模型为了说明各国出口结构对出口表现的影响，我们将从简单的知名需求替代模型开始。由于该模型常被用来讨论国际收支平衡，在因变量模型中有个价值维度。该模型的基本结构是：（q1p1/q2q2）j=fi(p1/p2) （2）其中Plj(P2j)等于通过1（2）来提供市场j的价格，qlj (q2j)等于从一个特定国际市场需求的商品供应1（2）。这两个进口商将被表示为I和II，ql(q2)代表1（2）的出口总额。主要区别是替代需求方法是通过介绍不同的市场允许处理出口因素。为了说明原因可以很容易的概括区别两个目标市场。如果假定这两个价格不变化，供应弹性是无限的，供应商不用价格歧视，通常的假设关于收入，价格弹性那么它的一些操作是：(q1P1)-(q2p2)=(q1ip1/q1p1-q2Ip2/q2p2)MI+（q1IIp1/q1p1-q2IIp2/q2p2）MII （2）MI和MII代表各自国家的进口需求值，它应该指出的是两个进口商是不同的目的地国的，表示一个变量的增长速度。（2）表明一个国家的出口增长比其他国家的快（慢），如果一个国家的出口额是I要比其他国家的多（少），如果在同一时间I的进口幅度比II的大（小）。换句话说，决定供应商成功与否的决定因素是出口的地区发布数据。三、区域出口业绩的喜好和供给因素影响3.1特定的区域偏好到现在为止都没有考虑到该地区进口商偏好差异的影响，认为增加某一特定市场的进口值将导致一个特定的进口需求的升华。在现实中各国具有特殊的区域性偏好，如前殖民地的关系，文化和政治的关系以及语言等。这些偏好可能会导致进口需求的变化使进口商之间竞争的商品有所不同。这些偏好的产品可以在时尚，款式，交易条件等方面有所差异。这些因素是更为相关的，如果在应用的实际模型中这个“商品”可能是典型的。另一项受到评论的是供给弹性是无限的假设，假设规模报酬和出口能力不变，扩大其国际需求的供应。有几个因素可能会导致假设的不成立。第一，个别出口商与国际市场总需求比特别小，虽然在扩大输出边缘但能力不够。第二，实证结果（格雷戈里，1971）表明即使出口价格停留在同一个商业周期，如果预期的规模报酬不变，非价格因素如交货时间，保证因素等。有可能大幅改变这表明规模报酬递减。这两种评价的方式是通过扩大进口商的不同点，并通过供应商进行，这样的出口价格和贸易流动是同时进行的。从政策角度而言最重要的是表明即使某一特定的出口国家和出口相对价格不威胁到它的相对出口表现，但其相对市场份额可能下滑