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 M II 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 country's exports, and if at the same time the increase
in I's imports is larger (smaller) than the increase in II's 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 country's exports can be broken down into parts which can be attributed to
the (given) composition of a country's 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，因为进口商不断扩大其需求比例。结果表明人们可能会区分两种竞争力：价格竞争力和非价格竞争力，后一种形式的竞争力是旨在改变进口商的特殊偏好。
3.2出口业绩对供应的影响
现在的问题是什么影响了市场份额的发展，是供应因素纳入模型使价格和贸易流动可以同时进行。要回答这个问题应该由国家提供的数据1和2，q1s 和 q2s不断增加的功能：
a) 他们各自产品的出口价格，P1和P2，如果相对价格可以在国内市场被接受分别是b1和b2。
b) 可为出口提供I 和C1。
c) 可为出口提供II 和CII 。
对B 和C 之间做出了明确的可能性，改变任何一个供应能力都有可能使供应商改变目的国。这个比例背后目的地市场规模差异可能会导致一种情况，例如由于规模因素，在一个特定区域发布的出口国出口略有增长偏离平均分配。
三、 例证
为了说明在不同模型下相关出口表现力的政策措施的影响，给予以下例子。我们的目标是要证明一个狭隘的因素是以确定相对出口业绩而可能会导致的错误和偏见的政策措施。在前一节所描述的模型a 将被归类到f 。
模型a 描述的是（1）。在这模型中的出口结构不以以下任何方式处理; 出口流量的大小仅仅被认为是需求因素的影响，他们只是函数的相对出口价格。这种模型不仅采用规范教科书上的替代模型标准图（参见Leamer 和Stern ，1970）；还有众多的进行了价值评估的需求函数，在国际贸易中具有了弹性的基本概念。
模型b 描述的是（2）。这个模型与模型a 是不同的，因为在这模型中注释了出口结构对出口影响的性能。为了方便在规划分布区可以办理出口。该模型可以扩大，但也可以处理商品结构。与前面模型相比，假设已经提出，但是相对价格没有改变因此不会影响市场中份额的变化。因为同意法律条款议价，所以通常被认为是坚持商品主要出口国家，价格在世界市场被确定。
模型c 描述的是（3）。这里的假设是由双方的出口和相对价格组成。这符合著名的恒定市场份额分析的出发点，根据其中一个国家出口结构的变化，格局可以被打破，可归结为一个国家出口的组成代表了国家竞争力的影响力。流动是觉得需求的唯一因素。
模型d 描述的是（13）。在与模型c 和模型d 比较下，这可能是进口商由不同偏好不同地区的供应商提供。这是特别合理的，如果模型中的商品有一种捆的特征，然而，所有的非经济因素也可以在双边贸易中存在偏好。该模型以后将被用于与实际有联系的长期数据。法国与德国已经被选为出口国，因为这些国家一方面有可观的经济规模，在贸易政策方面是会员政策，有远处的目的地市场还有大到足够稳定出口的模式。同时，这些国家的数据所表明的显著差异，说明他们适合现在的应用。此外，目的地国家将是美国和日本，因为这些市场都非常大，从这个时期的不同发展的这些市场需求来看，1960到1970的数据是十分明显的，因为这些数据适应于贫穷的非经合组织国家。应该强调的是程序的目标只是为了说明不同模型的含义。该数据的可靠性是否如此可以声称它本身所具有的价值。
前面模型的一个重要限制是没有注意贸易流动的方向。实际上，商品的出口结构在不同的出口国家大相径庭，并且根据结果分析可以预期出口业绩将被影响。因此，以前模型运用的两个被重复使用的商品数据分别是农业产品和工业产品。结果是确定了这两类商品的加权平均数并以此作为贸易份额的重点。后者的一个假设或多或少是基于与著名的Armington 国际贸易模型假设相吻合的，即进口商首先要对进口商品结构做个决定，在这之后要从另一方面决定进口区域的分布。
四、 结论
借助于贸易模型，使用两个不同的供应商和目的地其结果表明出口的组成不仅仅直接影响总出口的相对表现，而且可能间接拥有强大的影响力。其原因是出口组成也影响变量变化的灵敏度，出口总额的确定及出口商的竞争力。因此出口组成将构成竞争力的组成部分。其涵义是如果一个出口分析没有注意到这个现象，其结果可能是严重偏离导致的错误的政策结论将使成功或失败（一般）的错误的价格政策作为汇率政策。简单的运用法国和德国的出口数据对应美国和日本的弹性函数，从文献中有助于说明情况。
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 M II 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 country's exports, and if at the same time the increase
in I's imports is larger (smaller) than the increase in II's 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 country's exports can be broken down into parts which can be attributed to
the (given) composition of a country's 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，因为进口商不断扩大其需求比例。结果表明人们可能会区分两种竞争力：价格竞争力和非价格竞争力，后一种形式的竞争力是旨在改变进口商的特殊偏好。
3.2出口业绩对供应的影响
现在的问题是什么影响了市场份额的发展，是供应因素纳入模型使价格和贸易流动可以同时进行。要回答这个问题应该由国家提供的数据1和2，q1s 和 q2s不断增加的功能：
a) 他们各自产品的出口价格，P1和P2，如果相对价格可以在国内市场被接受分别是b1和b2。
b) 可为出口提供I 和C1。
c) 可为出口提供II 和CII 。
对B 和C 之间做出了明确的可能性，改变任何一个供应能力都有可能使供应商改变目的国。这个比例背后目的地市场规模差异可能会导致一种情况，例如由于规模因素，在一个特定区域发布的出口国出口略有增长偏离平均分配。
三、 例证
为了说明在不同模型下相关出口表现力的政策措施的影响，给予以下例子。我们的目标是要证明一个狭隘的因素是以确定相对出口业绩而可能会导致的错误和偏见的政策措施。在前一节所描述的模型a 将被归类到f 。
模型a 描述的是（1）。在这模型中的出口结构不以以下任何方式处理; 出口流量的大小仅仅被认为是需求因素的影响，他们只是函数的相对出口价格。这种模型不仅采用规范教科书上的替代模型标准图（参见Leamer 和Stern ，1970）；还有众多的进行了价值评估的需求函数，在国际贸易中具有了弹性的基本概念。
模型b 描述的是（2）。这个模型与模型a 是不同的，因为在这模型中注释了出口结构对出口影响的性能。为了方便在规划分布区可以办理出口。该模型可以扩大，但也可以处理商品结构。与前面模型相比，假设已经提出，但是相对价格没有改变因此不会影响市场中份额的变化。因为同意法律条款议价，所以通常被认为是坚持商品主要出口国家，价格在世界市场被确定。
模型c 描述的是（3）。这里的假设是由双方的出口和相对价格组成。这符合著名的恒定市场份额分析的出发点，根据其中一个国家出口结构的变化，格局可以被打破，可归结为一个国家出口的组成代表了国家竞争力的影响力。流动是觉得需求的唯一因素。
模型d 描述的是（13）。在与模型c 和模型d 比较下，这可能是进口商由不同偏好不同地区的供应商提供。这是特别合理的，如果模型中的商品有一种捆的特征，然而，所有的非经济因素也可以在双边贸易中存在偏好。该模型以后将被用于与实际有联系的长期数据。法国与德国已经被选为出口国，因为这些国家一方面有可观的经济规模，在贸易政策方面是会员政策，有远处的目的地市场还有大到足够稳定出口的模式。同时，这些国家的数据所表明的显著差异，说明他们适合现在的应用。此外，目的地国家将是美国和日本，因为这些市场都非常大，从这个时期的不同发展的这些市场需求来看，1960到1970的数据是十分明显的，因为这些数据适应于贫穷的非经合组织国家。应该强调的是程序的目标只是为了说明不同模型的含义。该数据的可靠性是否如此可以声称它本身所具有的价值。
前面模型的一个重要限制是没有注意贸易流动的方向。实际上，商品的出口结构在不同的出口国家大相径庭，并且根据结果分析可以预期出口业绩将被影响。因此，以前模型运用的两个被重复使用的商品数据分别是农业产品和工业产品。结果是确定了这两类商品的加权平均数并以此作为贸易份额的重点。后者的一个假设或多或少是基于与著名的Armington 国际贸易模型假设相吻合的，即进口商首先要对进口商品结构做个决定，在这之后要从另一方面决定进口区域的分布。
四、 结论
借助于贸易模型，使用两个不同的供应商和目的地其结果表明出口的组成不仅仅直接影响总出口的相对表现，而且可能间接拥有强大的影响力。其原因是出口组成也影响变量变化的灵敏度，出口总额的确定及出口商的竞争力。因此出口组成将构成竞争力的组成部分。其涵义是如果一个出口分析没有注意到这个现象，其结果可能是严重偏离导致的错误的政策结论将使成功或失败（一般）的错误的价格政策作为汇率政策。简单的运用法国和德国的出口数据对应美国和日本的弹性函数，从文献中有助于说明情况。