国际贸易理论与实务（英文）

nullInternational Trade Theory and PolicyInternational Trade Theory and PolicySchool of Economics, Yunnan University Zhang Jianhua and Zhang LinChap. 1 IntroductionChap. 1 IntroductionOne. Course Outline Basic theory in Economics ( Analysis of commodity and factor mobility in open Macro economy by tools Microeconomics Contents: Pure Theory in International Trade ( Reason and Influence of International Trade) Policy of International Trade （Policies aiming at limiting imports while encouraging exports） Institutions for International Trade（WTO Institutions ）Two Basic Concepts Two Basic Concepts balance of trade Trade Surplus（Exports＞Imports，Favorable Balance of Trade） Trade Deficit （Exports＜Imports，Unfavorable Balance of Trade） Trade Balance （Exports ＝ Imports） Trade Structure Commodity Structure Geographical Structure Dependency of Trade2004、2005年 中国的贸易收支2004年中国对外贸易依存度 接近70%2005年中国主要进出口商品Chap. 3 Comparative Cost and Classical Trade TheoremChap. 3 Comparative Cost and Classical Trade TheoremIn this chapter, we introduce theorem of international trade. We start such introduction looking at causes of international trade and its influences in the economy ( in Chap 3, 4, 5 and 6), then we will analyze the influences of economics in trade. One, Theory of Absolute CostTheory of absolute cost It is a theoretical explanation to the cause of international trade Introduced by Adam Smith in his “ Wealth of Nations”Graph of Absolute CostGraph of Absolute CostEach country produces goods absolutely low in cost, in exchange for other countries’ goods absolutely low in costTrade based on division of laborReason of trade is because of differences in absolute costCould countries have trade without absolute differences in cost?Chap 3. 2. Comparative CostChap 3. 2. Comparative CostDavid Ricardo，1817 Background谷物法Cultivation of wheat expands, land of grass shrinks, and price of wool goes up小麦价格上涨Labor is more expansiveFood expend increases, end goods expend decreasesRevenge from other countries, export of end products decrease损害了资产阶级的利益要求自由贸易Case of Ricardian ModelCase of Ricardian ModelAssumptions： Two nations, two products, one factor, fixed productivity, sufficient employment, perfect competition, non-mobility of factor, barter, no technological improvement, no transportation costThe absolute costs of both products in Britain is lower than that in Portugal, why is there still trade between these two countriesA necessary condition of international trade: Comparative cost differenceA necessary condition of international trade: Comparative cost differenceA sufficient condition of international trade: international exchange rate is between domestic exchange rates in both countries.There is benefit from tradeLimitation：Why there is comparative cost？Chap3. 3. Classical trade model based on comparative costChap3. 3. Classical trade model based on comparative costUsed to explain：Reasons and influences of trade ( Price, Production, Consumption and Welfare. 1, Analysis Tools1) Production Possibility Curve The maximum production when factors are fully employed. A（0，100）B（100，0）OXYC（X1，Y1）Property of Production Possibility CurveProperty of Production Possibility CurveSlope of PPC is equal to marginal opportunity costAB5434OXYThe cost of giving up one benefit for getting anotherMaximum cost may not be optimum production. We have to introduce indifference curve in order to get optimum production.2, Indifference Curve2, Indifference CurveThe different products combination that can bring same satisfaction to consumers.OXYA（10，40）B（25，15）UA=UBProperty of Indifference Curve: There are many indifference curve Further from origin means more utility level Never cross with each other Concave Negative SlopeThe combination of PPC and Indifference Curve: Equilibrium( Optimum ) Production and ConsumptionThe combination of PPC and Indifference Curve: Equilibrium( Optimum ) Production and ConsumptionOXYEACBU0U2U1ineffectiveImpossibleMaximum production, but utility less than EEquilibrium point： Maximum production, maximum utility3, Exchange Rate ( Comparative price and Trade condition3, Exchange Rate ( Comparative price and Trade conditionOYXABCDE1X = 1Y1X = 2Y3X = 3Y ★The exchange rate is equal to the slope of the line ★The key of exchange rate line is its slope, not the position. For example, AB and DE is in different position but has same slope二、贸易前均衡二、贸易前均衡开展国际贸易前，一国国内的生产和消费状况YXOBAT生产可能性曲线 边际机会成本为1X = 1Y交换比率线 交换比率为1X = 2YX产量扩大X价格下跌，比如： 1X = 1.5Y国内均衡时，生产可能性曲线与交换比率线重合，实现完全专业化生产根据生产可能性曲线的斜率 判断一国的比较优势根据生产可能性曲线的斜率 判断一国的比较优势YXOBAYXOB1A1A国B国1X = 1Y 相对于B国而言，X成本更低1X = 3Y 相对于A国而言，X成本更高，Y成本更低Three, Classical Trade Model ( One Factor )Three, Classical Trade Model ( One Factor )YXOABYXOCDTT1X = 1Y1X = 3YPrice of X falls in international market, and Price of Y also falls, finally reaches an equilibrium price, say, T(1X=2Y)National ANational BInfluence of International TradeInfluence of International TradeYXOABYXOCDTTEJU0U1U0U1FMPrice: X ( more comparative advantage ) raisedProduction：Production of X expanded ( Perfect specialization )Consumption: consumption combination is in higher-position indifference curve, better trade offX in Nation A: Production OB, Consumption OX0, Surplus X0B( Export ) Y in Nation A: Production: 0, Consumption OY0 ( imports)X0Y0X in nation B Production 0, consumption OX1( Imports) Y in nation Production OC, Consumption OY1, surplus Y1CX1Y1Chap. 4, Mutual Demands TheoryChap. 4, Mutual Demands TheoryUsed to explain how exchange rate is fixed, and how it varies.One, Terms of TradeT=PXPMPrice Index of exportsPrice Index of ImportsT：Improvement of trade condition: each unit of export can exchange for more importsT：Deterioration of trade condition: each unit of export exchanges for less importsChanges in Terms of TradeChanges in Terms of TradeYXOT0T1T2T3X0Y0Y1Y2Y3Improvement of Trade Condition in AYXOT3T2T1T0Y0X0X1X2X3Improvement of Trade Condition in BOffer CurveOffer CurveOXXYT0T1T2U0U1U2CABEFGLMNX0X1X2Y0Y1Y2T0：Export LA（= OX0），Import EL（= OY0）T1： Ex MB（= OX1），Im FM（= OY1）T2： EX NC（= OX2），Im GN（= OY2）T2T1T0Offer CurveEach point along offer curve means the equilibrium import and export in certain exchange rateGeneral Equilibrium in International TradeGeneral Equilibrium in International TradeOXYABTT1A1X0X1Y0Y1Equilibrium international exchange rateImprovement of trade condition for （That of B fixed）Offer Curve of A moves leftExports decrease greatly, but exchanged imports stay unchangedChap 5, Factor EndowmentChap 5, Factor EndowmentUsed to solve problems left behind by Ricardo: Reasons for comparative cost difference Put forward by Swedish Economists Heckscher and Ohiler, so it is also call the Heckscher-Ohlin model, or H-O model, also known as factor endowment theory. It offers good explaining to international trade, so still works as main stream theory in international trade.Chap5. 1. Heckscher-Ohlin ModelChap5. 1. Heckscher-Ohlin ModelOne, Assumptions1. Two nations, two products, two factors ( L and K ), 2× 2×2 model. 2. Fixed Endowment, free mobility of factor domestically, non-mobility internationally.3.Same technical level between two nations ( Same production function, same endowment for same products in two nations)Two, NotionsFactor intensityFactor abundance三、 Heckscher-Ohlin Theorem三、 Heckscher-Ohlin TheoremEach country exports the good intensive in the country's abundant factor, and imports the good intensive in the country’s scarce factor.两国要素禀赋不同，导致两国要素价格不同要素价格差异导致生产成本差异生产成本差异导致同种产品在两国的价格差异同种产品在不同国家价格的差异导致国际贸易发生两国要素密集度和要素丰 裕度的差异形成了不同产 品的比较优势Trade influence and benefitsTrade influence and benefitsProduction Possibility curve in case of two factorsYXOTUEDue to diminishing substitution of factors, marginal opportunity cost will increase, thus production possibility curve is concave.Its slope is the opportunity cost in point E. Equilibrium in E means marginal opportunity cost in E. Domestic equilibrium is equal to domestic price ratio.equilibriumX0Y0Trade influences : 1) priceTrade influences : 1) priceYXOEDomestic equilibrium pre trade. T is domestic exchange rateTT1After trade, the country export X, and its domestic supply of X decreases, and price X rises. TT1ATrade Influences 2) productionTrade Influences 2) productionYXOETT1SX0Y0X1Y1Since the international price of X is higher than that of domestic, production of X will increase, therefore, production of Y must decrease. Production combination will move to S.Since in S, the international exchange rate is equal to domestic marginal opportunity cost, the country’s production of X will not increase. With the increase of marginal opportunity cost, there will not be perfect specialization.ATrade Influences 3) ConsumptionTrade Influences 3) ConsumptionYXOETT1SAU0U1CAfter trade, consumers in the nation will be able to consume at international price T1, as budget constraint moves to U1, consumption combination moves to C. U1 is higher than U0, so consumers are better off. EquilibriumEquilibriumYXOETT1SU0U1CX1X2Y1Y2X： OX1-OX2=X2X1：ExY： OY1-OY2=Y1Y2：ImBenefit from TradeBenefit from TradeTrade makes a nation’s consumers better off, but have different influences to producers.Export ProducersDXSXQXPXOEQ0P0HGFP1Ex△HEP0： The export producers’ surplus pre trade△HGP1： The export producer’s surplus after trade. Difference：P1GEP0 Trade will benefit export producers. Influence to import competitive producersInfluence to import competitive producersDYSYQYPYOEP0P1FHImK△P1FK： Producer’s surplus after trade△P0EK： Producers’ surplus before tradeDifference：P0EFP1 Trade will harm the import competitive producers Chap. 5. 2. An empirical study of H-O modelChap. 5. 2. An empirical study of H-O model1, Leontif Paradox According to the statistical analysis of Leontif, he found out that U.S.A., which is a capital abundant country, imports more captial-intensive products, while exports more labor intensive goods. This is a paradox to H-O model. 2, Explain the Paradox Inverse of resource intensity Trade barriers Human resource Natural ResourcesH-O模型并没有错Chap5.3., Expansion of H-O modelChap5.3., Expansion of H-O modelInternational trade affects price production and consumption, but will it also affect the factor payoff and price? Basing on H-O model, we solve problems of trade to income distribution. Stolper-Samuelson TheoremFactor Payoff= Price（P）×Marginal products of factors（MP）Value of marginal products （VMP）W = P×MPLR = P×MPKShort term: Factor non-mobilityShort term: Factor non-mobilityBecause of non-mobility, trade will only affect price出口产品（X）价格上涨W = PX×MPLW increasesR = PX×MPKR increasesAll export producers’ payoffs increase进口产品（Y）价格下跌W = PY×MPLW DecreasesR = PY×MPKR DecreasesAll import producers’ payoffs decreaseLong term: Because factors are mobile, trade not only affects price, but also the marginal products.Long term: Because factors are mobile, trade not only affects price, but also the marginal products.劳动密集行的出口行业报酬提高资本密集型的进口竞争行业的要素向出口行业流动进口竞争行业流出的资本比劳动多出口行业需要的劳动比资本多资本相对过剩，价格降低 劳动相对稀缺，价格提高各行业投入更多资本，资本/劳动比率提高劳动生产率提高，资本生产率下降劳动的边际产品增加，资本的边际产品减少ContinueContinue出口行业W = PX×MPLPX上涨，MPL增加W提高R = PX×MPKPX上涨，MPK减少R？进口竞争行业W = PY×MPLPY下跌，MPL增加W？R = PY×MPKPY下跌，MPK减少R下降Payoff of the factor intensively used by exporters will increasePayoff of the factor intensively used by importers will decreaseContinueContinueLabor market is in equilibrium before tradeWX = WY，RX = RYFactor market will also form equilibrium after tradeWX increases，WY also increases； RX decreases，RY also decreasesIn long term, after trade, Payoff of the factor intensively used by exporters will increase, and Payoff of the factor intensively used by importers will decrease, this is try in any industry. Factor price equalization theoryFactor price equalization theoryExplains the influence of trade among countries to the factor price in two countries. A国贸易前W低R高贸易后W提高R降低B国贸易前W高R低贸易后W降低R提高均等Chap 6, New Trade TheoryChap 6, New Trade TheoryChanges in international Trade Increase of Intra-industry Trade Development of trade within developed countriesTrade between goods with similar or same endowmentsH-O cannot explainAmendments of assumptions of H-O model, develops to new trade theoryGeneral points of new trade theoriesGeneral points of new trade theoriesImperfect Competition Differentiated products (Intra-industry trade) Monopoly power ( price difference) Large – Scale Economy Internal ( enterprises) External ( Industry) Intra-industry trade and cross- industry tradeIntra-industry trade and cross- industry tradeDomestic （Rich in Capital）Foreign （Rich in labor ）productsFoodstuffCross-industry tradeIntra-industry tradeTrade due to external scale economyTrade due to external scale economyOne, in case of perfect competitionQPOD1S1P1AC1MC1P，COqq1Q1Before trade, supply and demand （S1，D1）determine equilibrium price （P1）, the MC and AC are MC1 and AC1. nullQPOD1S1P1AC1MC1P，COqq1Q1S2Enlarge of industry, supply, supply increases to S2AC2AC decreasesMeanwhile, market price falls, and trade happensQ2P2D2MC2Foreign demands increase, demand curves movesInternational price stays at P2Output from enterprises stay unchangedReason of trade is because of the price change due to external scale economy二、 Trade Equilibrium at external Scale of economy二、 Trade Equilibrium at external Scale of economyXYOProduction curve of increasing return to scale: diminishing marginal opportunity costETSuppose other conditions are same for two nations, equilibrium point is EUJHU1T1E1Suppose the production scale of two nations change, production combination moves to J and H, trade according to same exchange rate (T1) before tradeT2Trade is due to the price advantage of X when industry scale is expanded. Suppose X and Y are two products in same industryTrade due to Internal Scale of Economy: Imperfect competitive marketTrade due to Internal Scale of Economy: Imperfect competitive marketQOD1MR1MCQ1P1P，CEACSuppose marginal cost stay unchangedDue to scale of economy, average cost falls, enterprises will tradeD2MR2P2AC2Q2Demand curve and marginal income curve move right, but slope is less( more elasticity)Price （P2） in short ter is higher than average cost （AC2）, enterprise have monopoly profitNo monopoly profitLong term equilibriumLong term equilibriumQOP，CD2MR2MCQ2AC2P2ACShort term monopoly profitMR3D3Q3P3New firm enterDemand of the products decreasesExpansion of industry scale lower average cost, and competition eliminates monopoly profit.Scale of economy causes trade, which consequently increase consumer surplus( welfare improves), better specializationKrugman ModelKrugman ModelThree relations Relation of Quantity of producers and Average Cost: The bigger the quantity of producers, the less a single producer’s output, and AC is higher Relation of Quantity of producers and price: The more the producers, the more serious the competition, the lower the price. When price is higher than AC( has monopoly profit), other producers will go into the industry, while in other cases, when price is lower than AC( monopoly profit is negative), producers will go out of the industry. In graph, relation of quantity of producers and AC is CC curve( in positive relationship),; Relation of Quantity of producers and price is PP curve in the graph ( in negative relationship). In long term, quantity of producers is determined by the cross of two curves. ContinuedContinuedNP，CCCPPOEP1AC1N0N1P2AC2N2Monopoly profit exists, new producers go in, N increasesLoss, producers go out, N decreasesEquilibrium均衡Trade EquilibriumTrade EquilibriumNP，COPPCC1CC2N1N2P1P2E1E2Scale of economy lower the AC, has price advantage, exportThe lower AC makes CC curve moves right, new producers go in, N increasesMore competition means lower priceScale of economy causes lower price, bring with trade, improve consumer’s welfare, make producers specialized, scale of economy expands, and more choices for consumers. Products life cycle model ( technical transfer)Products life cycle model ( technical transfer)tExImOUSA：UKChina：Trade happens due to the technical difference, explains intra-industry trade in different timeChap 7, Economic growth and international tradeChap 7, Economic growth and international tradeSolve problems of the influence of economic variation to international tradeResource of growthIncrease of factors and technical improvementsIncrease of GDPResults of growthOXYABA1B1Balanced growth and unbalanced growthBalanced growth and unbalanced growthBalanced Growth O X Y A B EA1B1E1Same Slope O X Y A BUnbalanced growth C D F Gimport replacing growthexport expansion growthEconomic growth and tradeEconomic growth and tradeGrowth and trade of small country IRG O X Y A BTTCDU0U1FGHLMN OX Y A BTU0FGHU1LMNTEEGTrade condition stay unchanged, import and export change in same ratioTrade volume does not affect international exchange rate ( Trade condition )CDRybcZynski TheoremRybcZynski Theorem OX Y BTACDTX1X2Y1Y2The scale of decrease of X’s cost is larger than that of Y, so production of X will increase till equal to marginal opportunity cost ( slope of T ), output of Y is absolutely lower. Growth and trade for Large Country大国增长与贸易Growth and trade for Large Country大国增长与贸易Import replacing growthXOYABDCT0FEGHJKT1U0U1U2T2Welfare improves, HJ＞GF, due to international market price of Y falls, trade condition improves, the certain amount of the nation’s products could exchange for more import goods. Export expansion growthExport expansion growthXOYABT0FEGU0T1KHJU1U2T2Export of X increase for large country, which causes international market price of X falls, trade condition changes. Welfare improves. JK>FE, more export products are needed in exchange for a certain amount of import goods, trade condition deteriorates. CDImmiserizing growthImmiserizing growthYOXABCDTT1U0U1Chap 8, Protectionism and PoliciesChap 8, Protectionism and PoliciesWhen free trade can make two countries better off, why should there be trade protection? One, Policies of the mercantilism只有金银才是财富任何国家金银储量都是有限的，只有靠出口赚取别国金银才能增加本国财富同时要限制或禁止本国购买别国商品支出本国金银限制或禁止进口， 同时鼓励出口Two, Protection theory of ListTwo, Protection theory of ListThere should be different trade policies in different stages of economic development.Trade protectionism of KeynesianTrade protectionism of KeynesianAggregate Demand: C ＋ I ＋ G ＋ XAggregate Supply： C ＋ S ＋ T ＋ M＝消费投资政府支出出口消费储蓄进口政府收入Equation of Aggregate Demands Y ＝ C ＋ I ＋ G ＋（X－M）Net ExportTrade MultiplierTrade MultiplierConsumption Function： C＝Ca＋bY自发消费引致消费MPC X IncomeY＝Ca＋bY＋I＋G＋（X－M）不考虑Ca、I和GY＝bY＋（X－M）Y－bY＝（X－M）Y＝1 1－b（X－M）Let1 1－b＝k，Y＝k（X－M）In order to increase Y, needs to increase (X—M), or the exports, and decrease imports, then Y is increased by K times. New Trade protectionismNew Trade protectionismStrategic Trade policyPrisoner’s dilemmaABconfessNot confess confessNot confess5，510，11，100，0Nash equilibriumStrategic Trade policiesStrategic Trade policiesBoingAir busProduceNot produceProduceNot produce－5，－50，100100，00，0BoingAir busproduceNot ProduceProduceNot Produce－5，200，125100，00，0政府可以采取措施帮助本国企业获得战略性优势Other reasons for trade protectionOther reasons for trade protectionProtect young industries Protect industries whose average cost not higher than that of international market price in future Cost should be lower than the income of the industry in future Industry must be free join an exit Promote capital formation and industry multilateral Improve trade conditions and international balance of payments Increase employment and sustain high salary Promote economic development of developing countries.Chap 9, Trade management theories and policiesChap 9, Trade management theories and policiesLimited importTariffNon-tariff BarriersQuantity limitationsPrice limitationsPurchase controlFinancial controlTBTImprove exportExport creditNational Guarantee of export creditExport subsidyDumpingTariffTariffBasic Ideas（P.113~116）ERPERP＝V ’ －VVV ’ ＝（Final price of exports +Duty)– price of Imported materialV＝ price of foreign end products—foreign m