国际经济学克鲁格曼中文版第4章课件.ppt

1、第四章要素与贸易：赫克歇尔-俄林模型前言两要素经济模型两要素经济体间国际贸易的效应对赫克歇尔-俄林模型的实证分析提要附录：要素价格、产品价格以及投入的选择本章结构框架前言在现实世界中,劳动生产率之间的差异可以部分地解释贸易产生的原因，而贸易的产生同样反映了国家间资源禀赋的差异。赫克歇尔-俄林理论:强调要素禀赋的差异是贸易产生的唯一动因表明比较优势是受下列因素影响的：相对要素充裕度(就国家而言)相对要素密集度(就产品而言)还被称为要素比例理论模型的假设条件一个国家生产两种产品：棉布和粮食.两种产品的生产需要投入两种有限供给的要素：劳动（L）和土地（T）。两个国家中，粮食的生产是土地密集型的，而棉

2、布的生产是劳动密集型的。所有市场是完全竞争的。两要素经济模型/生产生产1卡路里粮食卡路里粮食所有可能的投入组合所有可能的投入组合生产生产1卡路里粮食投入卡路里粮食投入的土地的土地aTF（英亩）（英亩）生产生产1卡路里粮食投入卡路里粮食投入的劳动的劳动aLF（小时）（小时）两要素经济模型图图 4-1:粮食生产的要素投入组合粮食生产的要素投入组合要素密集度要素密集度 在两产品（棉布和粮食），两要素（劳动和土地）在两产品（棉布和粮食），两要素（劳动和土地）的世界中，如果在任何给定的实际工资率条件下，的世界中，如果在任何给定的实际工资率条件下，粮食生产中所使投入的土地粮食生产中所使投入的土地-劳动比率

3、都高于棉布生劳动比率都高于棉布生产的相应比率，那么粮食的生产是劳动密集型的产的相应比率，那么粮食的生产是劳动密集型的,：TF/LF TC/LC 比如比如:如果粮食的生产使用如果粮食的生产使用80个单位劳动力和个单位劳动力和20英亩土地，而棉布的生产使用英亩土地，而棉布的生产使用20单位劳动和单位劳动和20英英亩土地，那么我们就说粮食的生产是土地密集型亩土地，那么我们就说粮食的生产是土地密集型的，而棉布的生产是劳动密集型的。的，而棉布的生产是劳动密集型的。两要素经济模型CCFF工资工资-地租地租比率比率,w/r土地土地-劳动力劳动力比率比率,T/L两要素模型图图 4-2:要素价格和投入选择要素价

4、格和投入选择要素价格要素价格斯托尔珀-萨缪尔森定理(效应):在要素供给保持不变的条件下，若产品的相对价格上升，那么无论用哪种产品衡量，生产该产品所密集使用的要素的名义和实际收入就会提高，而其它要素的名义和实际收入就会减少。.反之亦然。两要素经济模型SS棉布的相对棉布的相对价格价格,PC/PF工资工资-地租比率地租比率,w/r两要素经济模型图图 4-3:要素价格和产品价格FFCCSS土地土地-劳动劳动比率比率,T/L棉布的相对棉布的相对价格价格,PC/PF工资工资-地租地租比率比率,w/r(PC/PF)1(TC/LC)2(TC/LC)1(TF/LF)2(TF/LF)1(w/r)2(w/r)1In

5、creasingIncreasing两要素经济模型(PC/PF)2如果棉布对于粮食的相对价格PC/PF上升，那么会:提高工人收入相对于土地所有者的收入，w/r。在棉布和粮食的生产中，提高土地相对于劳动的投入比率，从而提高劳动相对于土地的边际产出。由于用两种产品衡量的实际工资的提高和实际地租的减少，增强了工人的购买力而减弱土地所有者的购买力。两要素经济模型资源和产出资源的配置是如何决定的？在棉布的相对价格和土地劳动供给给定的条件下，就可以确定如何把这两种资源分配到两种产品的生产中去。两要素经济模型LFTFLCTC粮食生产中劳动的使用量粮食生产中劳动的使用量棉布生产中劳动使用量棉布生产中劳动使用量

6、OF增加增加增加增加增加增加增加增加棉布生产中土地使用量棉布生产中土地使用量粮食生产中土地使用两粮食生产中土地使用两1FCOC两要素经济模型图图 4-5:资源的配置当经济体的要素资源发生变化时，两种产品的产出会发生怎样的变化呢？雷布津斯基定理雷布津斯基定理(效应效应):在商品价格既定的条件下，如果一种生产要素量增加(T 或L)，那么密集使用该要素的产品的供给会增加，而其他产品的供给会减少。反之亦然。两要素经济模型CL2FL2CT1FT1CF1L1FL1CT2FT2C1两要素经济模型图图 4-6:土地供给增加 粮食生产中劳动使用量粮食生产中劳动使用量棉布生产中劳动土地量棉布生产中劳动土地量增加增

7、加增加增加增加增加增加增加腹胀生产中土地使用量腹胀生产中土地使用量粮食生产中土地使用量粮食生产中土地使用量F2O1FO2F2OCTT1TT2粮食产粮食产出出,QF棉布产棉布产出出,QC切线斜率切线斜率=-PC/PF切线斜率切线斜率=-PC/PF2Q2FQ2C1Q1FQ1C两要素经济模型图图 4-7:要素和生产可能性土地（劳动）供给的增加，会使生产可能性边界向偏于粮食或棉布生产的方向扩张。资源供给的变动对生产可能性边界的偏向性效应是理解资源差异如何导致国际贸易的关键。一个国家如果生产密集使用该国相对充裕要素的产品会更有效率。两要素经济模型赫克歇尔-俄林模型的假设:两个国家（本国和外国）有着:相同

8、的偏好相同的技术不同的资源禀赋本国劳动-土地比率高于外国每个国家使用两种生产要素，有着相同的生产函数国际贸易对两要素经济的影响相对价格与贸易模式要素充裕度 当且仅当本国可获得的劳动总量与土地总量的比率高于外国的对应比率时，即：L/T L*/T*就可以说相对外国而言，本国是一个劳动力充裕的国家（相对本国而言，外国是一个土地充裕的国家）例如:如果美国有8000万劳动力和2亿英亩土地，而英国有2000万劳动力和2以英亩土地，那么英国是劳动充裕的而美国是土地充裕的。.在这种情况下，本国的稀缺资源是土地，而外国的稀缺资源是劳动。国际贸易对两要素经济的影响当本国与外国相互贸易时，它们的价格会趋同。本国棉布

9、的相对价格会提高，外国棉布的相对价格会降低。在本国，棉布相对价格的提高会带来棉布生产的增加和相对消费的减少，所以本国成为棉布的出口方和粮食的进口方。相反地，外国棉布相对价格的下降会使外国成为棉布的进口方和粮食的出口方。国际贸易对两要素经济的影响RDRSRS*123国际贸易对两要素经济的影响图图 4-8:贸易使相对价格趋同棉布的相对棉布的相对价格价格,PC/PF棉布的相对棉布的相对产量产量,QC+Q*C QF+Q*F赫克歇尔赫克歇尔-俄林定理俄林定理:一个国家会出口密集使用该国充裕要素的产品，进口密集使用该国稀缺要素的产品。国际贸易对两要素经济的影响贸易和收入分配贸易导致相对价格趋同。对两个国家

10、，相对价格的改变对劳动和土地的相对收入会有重要影响：在本国,棉布的相对价格上升 劳动力所有者的福利状况改善而土地所有者的福利状况恶化。在外国，棉布的相对价格下降，相反的情形就会发生:劳动力所有者的福利状况恶化而土地所有者的福利状况改善国内充裕要素的所有者从贸易中获利，而稀缺要素的所有者因贸易而受损。国际贸易对两要素经济的影响特定要素模型与赫克歇尔-俄林模型在收入分配效应方面存在差异：生产要素对某个产业的特定性通常是一个短期问题例如:棉布的生产商不会一夜之间成为计算机生产商,但是只要有足够的时间，美国经济可以使衰落产业部门的工人转移到新兴产业部门中去。相反，贸易对土地、劳动和资本收入分配的影响基

11、本上是长期且持久的。.国际贸易对两要素经济的影响要素价格均等化在没有贸易的情况下，本国的劳动力的收益会比国外的劳动力的收益少，而本国土地的收益会比国外土地的收益多。要素价格均等化定理:国际贸易会使国家间同类要素的相对和绝对收益实现完全均等化。这意味着国际贸易可替代要素的国际流动性。国际贸易对两要素经济的影响在现实世界中，国家贸易已经使不同国家间同类要素的价格实现均等化了吗？随意考察一下就可清楚表明回答是否定的。例如:医生、工程师、技术人员、机械师以及劳动力所有者的工资在美国和德国与在韩国和墨西哥相比要高。在这样的情况下，与其说国际贸易完全消除了，还不如说国际贸易减弱了国家间同类要素收益的差异来

12、的更实际一点。国际贸易对两要素经济的影响国际贸易对两要素经济的影响表表 4-1:各国工资率的比较(美国=100)以下三个对预期要素价格均等化至关重要的前提假设在现实中是不成立的:两个国家同时生产两种相同的产品两个国家的 生产技术相同贸易使两个国家的产品价格相同要素价格均等化定理没有说明的一点是国际贸易会消除或减少单位资本收入的国际间差异。国际贸易对两要素经济的影响国际贸易对两要素经济的影响表表 4-2:发展中国家的制成品出口 (占进口国收入的百分比)对赫克歇尔-俄林模型的检验美国数据美国数据 里昂惕夫悖论里昂惕夫悖论 里昂惕夫发现，虽然美国是世界上资本最充裕的国家，但是美国的出口产品的资本密集

13、度要低于美国进口产品的资本密集度。全球数据全球数据 波文、利莫、斯维考斯克斯的一项研究利用大量国家的数据检验了赫克歇尔-俄林模型。.该项研究在世界范围证实了里昂惕夫悖论。对赫克歇尔-俄林模型的实证检验表表 4-3:1962年美国进出口产品包含的要素对赫克歇尔-俄林模型的实证检验对赫克歇尔-俄林模型的实证检验表表 4-4:检验赫克歇尔-俄林模型（美国=100）南北贸易的考察南北贸易的考察 尽管国际贸易的整个并不能很好的由模式赫克歇尔-俄林模型来解释，但南北制造品贸易看来比较符合这一理论。丢失贸易的情况 特拉夫勒1995年的一项研究表明样本国家间的技术差异是非常巨大的。对赫克歇尔-俄林模型的实证检

14、验对赫克歇尔-俄林模型的实证检验表表 4-5:1992年美国与韩国之间贸易额（单位：百万美元）对赫克歇尔-俄林模型的实证检验表表 4-6:估计技术效率，1983（美国=1）实证检验的含义通过对赫克歇尔-俄林模型的实证检验我们可以得出结论：该理论没能如人所愿成功地解释现实中的国际贸易模式。但该理论是一个分析贸易对收入分配影响的有效工具。对赫克歇尔-俄林模型的实证检验 赫克歇尔-俄林模型，是一个两产品、两要素的模型，它强调了资源禀赋在贸易中起到的作用。劳动密集型产品相对价格的上升会使收入分配急剧地向有利于劳动工人的方向转变。不论对哪种产品，即劳动的实际工资会上升而土地所有者的实际收入会减少。提要在

15、任何给定的产品价格下，生产要素的增加会使密集使用该要素的产品供给增加，而使其它不密集使用该要素的产品供给减少。赫克歇尔-俄林模型预期会出现以下的贸易模式:一个国家会出口密集使用该国充裕要素的产品，会进口密集使用该国稀缺要素的产品。提要提要一国充裕要素的所有者会从贸易中获益，而稀缺要素的所有者会因贸易而受损。在现实世界中，由于各国之间资源禀赋、生产技术上的巨大差异以及贸易壁垒的存在，要素价格的完全均等化是不存在的。对赫克歇尔-俄林模型的实证检验结论不统一大多数研究者认为，单以资源禀赋的差异不能很好的解释国际贸易的模式或世界要素价格。./生产生产1卡路里粮食投卡路里粮食投入的土地入的土地,aTF生

16、产生产1卡路里粮食投入卡路里粮食投入的劳动的劳动,aLF1等成本线等成本线附录：要素价格、产品价格以及投入选择图图 4A-1:选择最佳的土地-劳动比率/12附录：要素价格、产品价格以及投入选择图图 4A-2:改变工资-地租比率带来的影响生产生产1卡路里粮食投卡路里粮食投入的土地入的土地,aTF生产生产1卡路里粮食投入卡路里粮食投入的劳动的劳动,aLF斜率斜率=-(w/r)2斜率斜率=-(w/r)1FFCC斜率斜率=-(w/r)附录：要素价格、产品价格以及要素投入比率选择图图 4A-3:决定工资-地租比率土地投入量土地投入量劳动投入量劳动投入量FFCC1斜率斜率=-(w/r)1CC2斜率斜率=-

17、(w/r)2附录：要素价格、产品价格以及要素投入比率选择图图 4A-4:棉布价格上升的影响土地投入量土地投入量劳动投入量劳动投入量Chapter 4Resources and Trade:The Heckscher-Ohlin ModelIntroductionA Model of a Two-Factor EconomyEffects of International Trade Between Two-Factor EconomiesEmpirical Evidence on the Heckscher-Ohlin ModelSummaryAppendix:Factor Prices,Go

18、ods Prices,and Input ChoicesChapter OrganizationIntroductionIn the real world,while trade is partly explained by differences in labor productivity,it also reflects differences in countries resources.The Heckscher-Ohlin theory:Emphasizes resource differences as the only source of tradeShows that comp

19、arative advantage is influenced by:Relative factor abundance(refers to countries)Relative factor intensity(refers to goods)Is also referred to as the factor-proportions theoryAssumptions of the ModelAn economy can produce two goods,cloth and food.The production of these goods requires two inputs tha

20、t are in limited supply;labor(L)and land(T).Production of food is land-intensive and production of cloth is labor-intensive in both countries.Perfect competition prevails in all markets.A Model of a Two-Factor Economy/Input combinations that produce one calorie of foodUnit land input aTF,in acres pe

21、r calorieUnit land input aLF,in hours per calorieA Model of a Two-Factor EconomyFigure 4-1:Input Possibilities in Food ProductionFactor Intensity In a world of two goods(cloth and food)and two factors(labor and land),food production is land-intensive,if at any given wage-rental ratio the land-labor

22、ratio used in the production of food is greater than that used in the production of cloth:TF/LF TC/LC Example:If food production uses 80 workers and 200 acres,while cloth production uses 20 workers and 20 acres,then food production is land-intensive and cloth production is labor-intensive.A Model of

23、 a Two-Factor EconomyCCFFWage-rental ratio,w/rLand-laborratio,T/LA Model of a Two-Factor EconomyFigure 4-2:Factor Prices and Input ChoicesFactor Prices and Goods PricesStolper-Samuelson Theorem(effect):If the relative price of a good increases,holding factor supplies constant,then the nominal and re

24、al return(in terms of both goods)to the factor used intensively in the production of that good increases,while the nominal and real return(in terms of both goods)to the other factor decreases.The reverse is also true.A Model of a Two-Factor EconomySSRelative price ofcloth,PC/PFWage-rentalratio,w/rA

25、Model of a Two-Factor EconomyFigure 4-3:Factor Prices and Goods PricesFFCCSSLand-labor Ratio,T/LRelativeprice ofcloth,PC/PFWage-rentalratio,w/r(PC/PF)1(TC/LC)2(TC/LC)1(TF/LF)2(TF/LF)1(w/r)2(w/r)1IncreasingIncreasingA Model of a Two-Factor EconomyFigure 4-4:From Goods Prices to Input Choices(PC/PF)2A

26、n increase in the price of cloth relative to that of food,PC/PF,will:Raise the income of workers relative to that of landowners,w/r.Raise the ratio of land to labor,T/L,in both cloth and food production and thus raise the marginal product of labor in terms of both goods.Raise the purchasing power of

27、 workers and lower the purchasing power of landowners,by raising real wages and lowering real rents in terms of both goods.A Model of a Two-Factor EconomyResources and OutputHow is the allocation of resources determined?Given the relative price of cloth and the supplies of land and labor,it is possi

28、ble to determine how much of each resource the economy devotes to the production of each good.A Model of a Two-Factor EconomyLFTFLCTCLabor used in food productionLabor used in cloth productionOFIncreasingIncreasingIncreasingIncreasingLand used in cloth productionLand used in food production1FCOCA Mo

29、del of a Two-Factor EconomyFigure 4-5:The Allocation of ResourcesHow do the outputs of the two goods change when the economys resources change?Rybczynski Theorem(effect):If a factor of production(T or L)increases,then the supply of the good that uses this factor intensively increases and the supply

30、of the other good decreases for any given commodity prices.The reverse is also true.A Model of a Two-Factor EconomyCL2FL2CT1FT1CF1L1FL1CT2FT2C1A Model of a Two-Factor EconomyFigure 4-6:An Increase in the Supply of LandLabor used in food productionLabor used in cloth productionIncreasingIncreasingInc

31、reasingIncreasingLand used in cloth productionLand used in food productionF2O1FO2F2OCTT1TT2Output offood,QFOutput ofcloth,QCSlope=-PC/PFSlope=-PC/PF2Q2FQ2C1Q1FQ1CA Model of a Two-Factor EconomyFigure 4-7:Resources and Production PossibilitiesAn increase in the supply of land(labor)leads to a biased

32、expansion of production possibilities toward food(cloth)production.The biased effect of increases(decreases)in resources on production possibilities is the key to understanding how differences in resources give rise to international trade.An economy will tend to be relatively effective at producing

33、goods that are intensive in the factors with which the country is relatively well-endowed.A Model of a Two-Factor EconomyAssumptions of the Heckscher-Ohlin model:There are two countries(Home and Foreign)that have:Same tastes Same technology Different resources Home has a higher ratio of labor to lan

34、d than Foreign doesEach country has the same production structure of a two-factor economy.Effects of International Trade Between Two-Factor EconomiesRelative Prices and the Pattern of TradeFactor Abundance Home country is labor-abundant compared to Foreign country(and Foreign is land-abundant compar

35、ed to Home)if and only if the ratio of the total amount of labor to the total amount of land available in Home is greater than that in Foreign:L/T L*/T*Example:if America has 80 million workers and 200 million acres,while Britain has 20 million workers and 20 million acres,then Britain is labor-abun

36、dant and America is land-abundant.In this case,the scarce factor in Home is land and in Foreign is labor.Effects of International Trade Between Two-Factor EconomiesWhen Home and Foreign trade with each other,their relative prices converge.The relative price of cloth rises in Home and declines in For

37、eign.In Home,the rise in the relative price of cloth leads to a rise in the production of cloth and a decline in relative consumption,so Home becomes an exporter of cloth and an importer of food.Conversely,the decline in the relative price of cloth in Foreign leads it to become an importer of cloth

38、and an exporter of food.Effects of International Trade Between Two-Factor EconomiesRDRSRS*123Effects of International Trade Between Two-Factor EconomiesFigure 4-8:Trade Leads to a Convergence of Relative PricesRelative price of cloth,PC/PFRelative qualityof cloth,QC+Q*C QF+Q*FHeckscher-Ohlin Theorem

39、:A country will export that commodity which uses intensively its abundant factor and import that commodity which uses intensively its scarce factor.Effects of International Trade Between Two-Factor EconomiesTrade and the Distribution of IncomeTrade produces a convergence of relative prices.Changes i

40、n relative prices have strong effects on the relative earnings of labor and land in both countries:In Home,where the relative price of cloth rises:Laborers are made better off and landowners are made worse off.In Foreign,where the relative price of cloth falls,the opposite happens:Laborers are made

41、worse off and landowners are made better off.Owners of a countrys abundant factors gain from trade,but owners of a countrys scarce factors lose.Effects of International Trade Between Two-Factor EconomiesDifference between the specific factors model and the Heckscher-Ohlin model in terms of income di

42、stribution effects:The specificity of factors to particular industries is often only a temporary problem.Example:Garment makers cannot become computer manufactures overnight,but given time the U.S.economy can shift its manufacturing employment from declining sectors to expanding ones.In contrast,eff

43、ects of trade on the distribution of income among land,labor,and capital are more or less permanent.Effects of International Trade Between Two-Factor EconomiesFactor Price EqualizationIn the absence of trade:labor would earn less in Home than in Foreign,and land would earn more.Factor-Price Equaliza

44、tion Theorem:International trade leads to complete equalization in the relative and absolute returns to homogeneous factors across countries.It implies that international trade is a substitute for the international mobility of factors.Effects of International Trade Between Two-Factor EconomiesHas in

45、ternational trade equalized the returns to homogeneous factors in different countries in the real world?Even casual observation clearly indicates that it has not.Example:Wages are much higher for doctors,engineers,technicians,mechanics and laborers in the United States and Germany than in Korea and

46、Mexico.Under these circumstances,it is more realistic to say that international trade has reduced,rather than completely eliminated,the international difference in the returns to homogeneous factors.Effects of International Trade Between Two-Factor EconomiesEffects of International Trade Between Two

47、-Factor EconomiesTable 4-1:Comparative International Wage Rates(United States=100)Three assumptions crucial to the prediction of factor price equalization are in reality untrue:Both countries produce both goods Both countries have the same technologies in production Both countries have the same pric

48、es of goods due to tradeOne thing the factor-price equalization theorem does not say is that international trade will eliminate or reduce international differences in per capita incomes.Effects of International Trade Between Two-Factor EconomiesEffects of International Trade Between Two-Factor Econo

49、miesTable 4-2:Composition of Developing-Country Exports (Percent of Total)Testing the Heckscher-Ohlin ModelTests on U.S.Data Leontief paradox Leontief found that U.S.exports were less capital-intensive than U.S.imports,even though the U.S.is the most capital-abundant country in the world.Tests on Gl

50、obal Data A study by Bowen,Leamer,and Sveikauskas tested the Heckscher-Ohlin model using data for a large number of countries.This study confirms the Leontief paradox on a broader level.Empirical Evidence on the Heckscher-Ohlin ModelTable 4-3:Factor Content of U.S.Exports and Imports for 1962Empiric