复旦大学国际贸易International Trade课件英文原版(5)

1、To Accompany , Sixth Editionby Paul R. Krugman and Maurice ObstfeldCopyright 2003 Pearson Education, Inc.Slide 5-2Chapter OrganizationIntroductionA Standard Model of a Trading EconomyInternational Transfers of Income: Shifting the RD CurveTariffs and Export Subsidies: Simultaneous Shifts in RS and R

2、DSummaryAppendix: Representing International Equilibrium with Offer CurvesCopyright 2003 Pearson Education, Inc.Slide 5-3IntroductionPrevious trade theories have emphasized specific sources of comparative advantage which give rise to international trade:Differences in labor productivity (Ricardian m

3、odel)Differences in resources (specific factors model and Heckscher-Ohlin model)The standard trade model is a general model of trade that admits these models as special cases.Copyright 2003 Pearson Education, Inc.Slide 5-4A Standard Model of a Trading EconomyThe standard trade model is built on four

4、 key relationships:Production possibility frontier and the relative supply curveRelative prices and relative demandWorld relative supply and world relative demandTerms of trade and national welfareCopyright 2003 Pearson Education, Inc.Slide 5-5A Standard Model of a Trading EconomyProduction Possibil

5、ities and Relative SupplyAssumptions of the model: Each country produces two goods, food (F) and cloth (C) Each countrys production possibility frontier is a smooth curve (TT)The point on its production possibility frontier at which an economy actually produces depends on the price of cloth relative

6、 to food, PC/PF.Iso-value lines Lines along which the market value of output is constantCopyright 2003 Pearson Education, Inc.Slide 5-6Figure 5-1: Relative Prices Determine the Economys OutputQIsovalue linesTTA Standard Model of a Trading Economy Cloth production, QCFood production, QFCopyright 2003

7、 Pearson Education, Inc.Slide 5-7Figure 5-2: How an Increase in the Relative Price of Cloth Affects Relative SupplyQ1VV1(PC/PF)1Q2VV2(PC/PF)2A Standard Model of a Trading EconomyTT Cloth production, QCFood production, QFCopyright 2003 Pearson Education, Inc.Slide 5-8Relative Prices and DemandThe val

8、ue of an economys consumption equals the value of its production:PCQC + PFQF = PCDC + PFDF = VThe economys choice of a point on the isovalue line depends on the tastes of its consumers, which can be represented graphically by a series of indifference curves.A Standard Model of a Trading EconomyCopyr

9、ight 2003 Pearson Education, Inc.Slide 5-9Indifference curves Each traces a set of combinations of cloth (C) and food (F) consumption that leave the individual equally well off They have three properties: Downward sloping The farther up and to the right each lies, the higher the level of welfare to

10、which it corresponds Each gets flatter as we move to the rightA Standard Model of a Trading EconomyCopyright 2003 Pearson Education, Inc.Slide 5-10TTFigure 5-3: Production, Consumption, and Trade in the Standard Model Cloth production, QCFood production, QFQDIndifference curvesFood importsCloth expo

11、rtsA Standard Model of a Trading EconomyCopyright 2003 Pearson Education, Inc.Slide 5-11If the relative price of cloth, PC/PF , increases, the economys consumption choice shifts from D1 to D2. The move from D1 to D2 reflects two effects: Income effect Substitution effect It is possible that the inco

12、me effect will be so strong that when PC/PF rises, consumption of both goods actually rises, while the ratio of cloth consumption to food consumption falls.A Standard Model of a Trading EconomyCopyright 2003 Pearson Education, Inc.Slide 5-12TTFigure 5-4: Effects of a Rise in the Relative Price of Cl

13、othQ1VV1(PC/PF)1Q2VV2(PC/PF)2D2D1A Standard Model of a Trading Economy Cloth production, QCFood production, QFCopyright 2003 Pearson Education, Inc.Slide 5-13The Welfare Effect of Changes in the Terms of TradeTerms of trade The price of the good a country initially exports divided by the price of th

14、e good it initially imports. A rise in the terms of trade increases a countrys welfare, while a decline in the terms of trade reduces its welfare.A Standard Model of a Trading EconomyCopyright 2003 Pearson Education, Inc.Slide 5-14Determining Relative PricesSuppose that the world economy consists of

15、 two countries: Home (which exports cloth) Its terms of trade are measured by PC/PF Its quantities of cloth and food produced are QC and QF Foreign (which exports food) Its terms of trade are measured by PF/PC Its quantities of cloth and food produced are Q*C and Q*FA Standard Model of a Trading Eco

16、nomyCopyright 2003 Pearson Education, Inc.Slide 5-15To determine PC/PF , one must find the intersection of world relative supply of cloth and world relative demand. The world relative supply curve (RS) is upward sloping because an increase in PC/PF leads both countries to produce more cloth and less

17、 food. The world relative demand curve (RD) is downward sloping because an increase in PC/PF leads both countries to shift their consumption mix away from cloth toward food.A Standard Model of a Trading EconomyCopyright 2003 Pearson Education, Inc.Slide 5-16Figure 5-5: World Relative Supply and Dema

18、ndRSRDRelative priceof cloth, PC/PFRelative quantityof cloth, QC + Q*C QF + Q*FA Standard Model of a Trading Economy(PC/PF)11Copyright 2003 Pearson Education, Inc.Slide 5-17Economic Growth: A Shift of the RS CurveIs economic growth in other countries good or bad for our nation? It may be good for ou

19、r nation because it means larger markets for our exports. It may mean increased competition for our exporters.Is growth in a country more or less valuable when that nation is part of a closely integrated world economy? It should be more valuable when a country can sell some of its increased producti

20、on to the world market. It is less valuable when the benefits of growth are passed on to foreigners rather than retained at home.A Standard Model of a Trading EconomyCopyright 2003 Pearson Education, Inc.Slide 5-18Growth and the Production Possibility FrontierEconomic growth implies an outward shift

21、 of a countrys production possibility frontier (TT).Biased growth Takes place when TT shifts out more in one direction than in the other Can occur for two reasons: Technological progress in one sector of the economy Increase in a countrys supply of a factor of productionA Standard Model of a Trading

22、 EconomyCopyright 2003 Pearson Education, Inc.Slide 5-19Figure 5-6: Biased GrowthTT1TT1TT2TT2A Standard Model of a Trading EconomyCloth production, QCFood production, QF(a) Growth biased toward clothCloth production, QCFood production, QF(b) Growth biased toward foodCopyright 2003 Pearson Education,

23、 Inc.Slide 5-20Relative Supply and the Terms of TradeExport-biased growth Disproportionately expands a countrys production possibilities in the direction of the good it exports Worsens a growing countrys terms of trade, to the benefit of the rest of the worldImport-biased growth Disproportionately e

24、xpands a countrys production possibilities in the direction of the good it imports Improves a growing countrys terms of trade at the rest of the words expenseA Standard Model of a Trading EconomyCopyright 2003 Pearson Education, Inc.Slide 5-21Figure 5-7: Growth and Relative SupplyRelative priceof cl

25、oth, PC/PFRelative quantityof cloth, QC + Q*C QF + Q*FRS1RD1(PC/PF)1RS2(PC/PF)22Relative priceof cloth, PC/PFRelative quantityof cloth, QC + Q*C QF + Q*FRS2RD2(PC/PF)2RS1(PC/PF)11(a) Cloth-biased growth(b) Food-biased growthA Standard Model of a Trading EconomyCopyright 2003 Pearson Education, Inc.S

26、lide 5-22International Effects of GrowthExport-biased growth in the rest of the world improves our terms of trade, while import-biased growth abroad worsens our terms of trade.Export-biased growth in our country worsens our terms of trade, reducing the direct benefits of growth, while import-biased

27、growth leads to an improvement of our terms of trade.A Standard Model of a Trading EconomyCopyright 2003 Pearson Education, Inc.Slide 5-23Immiserizing growth A situation where export-biased growth by poor nations can worsen their terms of trade so much that they would be worse off than if they had n

28、ot grown at all It can occur under extreme conditions: Strongly export-biased growth must be combined with very steep RS and RD curves. (RS上升时，由于RD较陡，故价格下降很多；RD增加时，由于RS较陡，故需求量增加很少） It is regarded by most economists as more a theoretical point than a real-world issue.A Standard Model of a Trading Eco

29、nomyCopyright 2003 Pearson Education, Inc.Slide 5-24International Transfers of Income: Shifting the RD CurveInternational transfers of income, such as war reparations and foreign aid, may affect a countrys terms of trade by shifting the world relative demand curve.Relative world demand for goods may

30、 shift because of:Changes in tastesChanges in technologyInternational transfers of incomeThe Transfer ProblemHow international transfers affect the terms of tradeCopyright 2003 Pearson Education, Inc.Slide 5-25Effects of a Transfer on the Terms of TradeWhen both countries allocate their change in sp

31、ending in the same proportions (Ohlins point): The RD curve will not shift, and there will be no terms of trade effect.When the two countries do not allocate their change in spending in the same proportions (Keyness point): The RD curve will shift and there will be a terms of trade effect. The direc

32、tion of the effect on terms of trade will depend on the difference in Home and Foreign spending patterns.International Transfers of Income: Shifting the RD CurveCopyright 2003 Pearson Education, Inc.Slide 5-26Figure 5-8: Effects of a Transfer on the Terms of TradeRelative priceof cloth, PC/PFRelativ

33、e quantityof cloth, QC + Q*C QF + Q*FRSRD2RD1(PC/PF)221(PC/PF)1International Transfers of Income: Shifting the RD CurveCopyright 2003 Pearson Education, Inc.Slide 5-27Presumptions about the Terms of Trade Effects of TransfersA transfer will worsen the donors terms of trade if the donor has a higher

34、marginal propensity to spend on its export good than the recipient.In practice, most countries spend a much higher share of their income on domestically produced goods than foreigners do. This is not necessarily due to differences in taste but rather to barriers to trade, natural and artificial.Inte

35、rnational Transfers of Income: Shifting the RD CurveCopyright 2003 Pearson Education, Inc.Slide 5-28SummaryThe standard trade model provides a framework that can be used to address a wide range of international issues and admits previous trade models as special cases.A countrys terms of trade are de

36、termined by the intersection of the world relative supply and demand curves.Economic growth is usually biased. Growth that is export-biased (import-biased) worsens (improves) the terms of trade.Copyright 2003 Pearson Education, Inc.Slide 5-29International transfers of income may affect a countrys terms of tra