《国际经济学讲义》PPT课件(32页PPT)

1、 Why Counties Trade（the classical model of international trade）第1页，共32页。Chapter OrganizationIntroductionTrade Based on Absolute AdvantageTrade Based on Comparative AdvantageTrade Based on Opportunity CostsThe Production Possibilities Frontier and Constant CostsThe Terms of TradeTrade Under Increasin

2、g Opportunity CostsDynamic Gains from Trade第2页，共32页。IntroductionIn this chapter, we first discuss international trade based on Adam Smiths theory of absolute advantage. Then, we explain the pattern of trade and the gains from trade based on David Richards theory of comparative advantage. We also exp

3、lain the theory of comparative advantage in terms of opportunity cost. Finally, we describe the gains from trade that are difficult to quantify and occur over time.第3页，共32页。International Trade Versus Interregional TradeInternational trade and Interregional trade are similar. international means betw

4、een two or more countries. Inter-regional (domestic trade) means between two or more regions, where a region is a part of a country. Benefits of Trade: -specialization and trade makes total world output of goods and services larger than it would be without trade第4页，共32页。Difference between internatio

5、nal trade and interregional tradeNational currency; Trade policy; Market development; Culture and customs; law, etc第5页，共32页。1.Three basic questions about international tradeWhy do countries export and import certain goods?At what price are products exchanged in world market?What are the gains from i

6、nternational trade In terms of production and consumption?第6页，共32页。2.The Mercantilism and its standpointsDuring 1500-1700,the doctrine of mercantilism domin-ated political and economic thought .The premise: a country can promote its self-interest by discouraging imports and encouraging exports ;a co

7、untry wealth was precious metal, gold and silverA favorable trade balance: a surplus of exports over imports.Mercantilists advocating: tariffs, quotas, and other trading protectionism policies.David Humes price-specie-flow doctrine: a favorable trade balance was possible only in the short run, for o

8、ver time it would automatically be eliminated.Video 3 video 2第7页，共32页。3.Adam Smiths theory of absolute advantageAdam Smith: The Wealth of Nations ,1776International trade is not a zero-sum game.The gains from trade are the increase in world output that results from each country specializing its prod

9、uc-tion according to absolute advantage (absolute cost).Absolute advantage is the ability of a country to use fewer resources to produce a good than other countries.第8页，共32页。assumption :the labor theory of valueLabor is the only factor of production and is homo-geneous.The cost or the price of a goo

10、d depends exclusively on the amount of labor第9页，共32页。 a example about absolute advantageAssumption:2-nation:the U.S. and India, 2-product:machine and cloth,1-factor:labor ;technology (constant) ; transportation cost (zero) ;free trade . Absolute advantage is the ability of a country to use fewer res

11、ources to produce a good than other countries. The U.S. has an absolute advantage in machine production, while India has an absolute advantage in cloth production.第10页，共32页。 countrymachinescloth U.S.5 machines10 yards of clothIndia2 machines15 yards of clothTable 1 autarky (a closed economy) One per

12、son per day of labor ProductsTable 2 open economy countrymachinescloth U.S.+5 machines-10 yards of clothIndia-2 machines+15 yards of clothChanging in world output+3 machines+ 3 yards of cloth第11页，共32页。The theory of absolute advantageIn a two-nation, two-product world , international trade and specia

13、lization will be beneficial when one nation has an absolute cost advantage in one good and the other nation has an absolute cost advantage in the other good. 第12页，共32页。4.David Ricardos theory of comparative advantageAn unanswered question: why would trade occur betw-een two countries if one country

14、had an absolute adv-antage in the two goods?countrymachinesCloth relative costU.S.5 machines15 yards of cloth 1M=3CIndia1 machines5 yards of cloth 1M=5C U.S.the degree of absolute advantage: machine 5-to-1,cloth 3-to-1.the U.S. has a comparative advantage in machine. India has a comparative advantag

15、e in cloth.第13页，共32页。 countrymachinescloth U.S.+5 machines-15 yards of clothIndia-3 machines+15 yards of clothChanging in world output+2 machines 0 yards of clothFree trade according comparative advantage the gain from specialization and trade is the increase in world output that results from each c

16、ountry specializing its production according to its comparative advantage.第14页，共32页。The theory of Comparative advantage The more efficient nation should specialize in and export the goods in which it is re-latively more efficient. The less efficient nation should specialize in and export the goods i

17、n which it is relatively less in-efficient. 第15页，共32页。5.General Trade theories: Based on Opportunity CostsOpportunity cost: opportunity cost is the amount of a goodmachine-that must be given up to release enough resources to produce another good-cloth.countrymachinesCloth opportunity costU.S.5 machi

18、nes15 yards of cloth 1M=3CIndia1 machines5 yards of cloth 1M=5C Marginal rate of transformation (MRT): The MRT shows the amount of one good that a country must sacrifice to get one additional unit of another good. MRT=Cloth/Machine第16页，共32页。5.1 The gains from trade with opportunity costFor profitabl

19、e exchange to take place, the price machines relative to the price of cloth would have to be between 1M=3C and 1M=5C. If 1M=4CU.S.IndiaProduction at full employment100 machines0 yards of cloth0 machines300 yards of clothconsumption with trade1M=4C50 machines200 yards of cloth50 machines100 yards of

20、clothAutarkyU.S. 1M=3CIndia 1M=5C50 machines150 yards of cloth40 machines100 yards of clothGains from trade50 yards of cloth10 machines第17页，共32页。Production possibilities frontier (PPF) shows the different combinations of two goods that can be produced when all of a countrys factors of production are

21、 fully employed in their most efficient manner.Constant cost U.S.Indiamachinesclothmachinescloth100060090305050806040100709030150601202020050150102504018003003021020240102700300第18页，共32页。5.2 The Production Possibilities Frontier and Constant CostsThe opportunity cost or MRT for each country is equal

22、 to the slope of the PPF. Under perfectly competitive, Pm/Pc=3( U.S.), Pm/Pc=5(India)Slope=MRT=-3=- Pm/PcSlope=MRT=-5=- Pm/Pc第19页，共32页。Production and Consumption without specializa-tion and trade -Without specialization and trade, the U.S. and India can produce and consume at any point along their r

23、espective PPF.- Because the opportunity costs are different in the two countries ,mutually beneficial trade is possible. 第20页，共32页。 Production and Consumption with specialization and trade 1M=4C200EexportimportDF50EFDexportimportTrading triangle: EFD and EFDDG or DG is called trading possibilities c

24、urvetheThe terms of trade :1M=4CGG第21页，共32页。Production and Consumption with specialization and trade as a result of international specialization and trade, the U.S. and India can both have levels of consumption that are superior to those attainable on their production possibilities frontiers. 第22页，共

25、32页。Changes in the gains from speciation and trade as the terms of trade change (from 1M=4C to 1M=3.5C ), the trading possibilities frontier rotates for both countries. Indias consumption point moves from E to F and the U.S. consumption point moves from E to F . the closer the ratio moves toward 1M=

26、3C,the more favorable the exchange is for India.第23页，共32页。5.3 The terms of trade and distribution of the gains from tradeterms of trade: it measures the relationship between the prices a nation gets for its exports and the prices it pays for its imports. terms of trade = (exports prices index)/(impo

27、rts prices index) 100%Conclusion:an improvement in a countrys terms of trade does not necessarily reflect an improvement in a countrys overall welfare.An improvement in a countrys terms of trade resulting from a change in international conditions will enhance the country welfare.When the terms of tr

28、ade change as a result of a change in domestic economic conditions. The effect on a countrys welfare is uncertain.第24页，共32页。5.4 Demand condition and the terms of tradeThe theory of reciprocal demand (pointed out by John Stuart Mill,1921)suggests that the actual international exchange ratio at which

29、trade takes place depends on each trading partners interacting demands.the reciprocal demand theory indicates that the final international exchange ratio depends on the relative strength of each countrys demand for the other countrys product.If two countries are of unequal (population and income), i

30、t is possible that the larger countrys demand would be greater than the smaller countrys demand. As a result ,the smaller country gains from than the larger country.第25页，共32页。5.5 Constant cost 、Complete specialization and PPFComplete specialization: the use of all of a countrys resources to produce

31、only one good. Supply Curves of a Good and the Production Possibilities Frontier Under Constant Cost Conditions Constant opportunity costs lead to straight-line production possibili-ties frontiers and supply curves for goods that are horizontal.第26页，共32页。y2y1x2x1x3Y3 5.6 Increasing opportunity cost

32、and PPFIncreasing opportunity costs lead to production possibilities frontiers that are concave to the origin and supply curves for goods that are upward slopingIncreasing opportunity costY4X4machinesclothmachinespricesupply第27页，共32页。Production Possibilities Curve with Increasing Costs and the Margi

33、nal Rate of Transformation Undetr increasing cost ,the slop of the PPF at point B is equal to the slope of the tangent line DE. Similarly , the slope of the PPF at point C is equal to the slope of the tangent line FG. The tangent line DE is flatter than the tangent line FG. slopeDE =MRTDE slopeFG =M

34、RTFG 第28页，共32页。5.7 Production and consumption without specialization and tradeWithout trade, U.S decides to produce at point A. India decides to produce at point A.Opportunity cost: in the U.S. 1M=3C.In India,1M=5CComparative advantage: U.S. (Machines) India (cloth)clothclothMachinesMachinesAACD CDS

35、lope=MRT=-5Slope=MRT=-3IndiaU.S.第29页，共32页。as a result of international specialization and trade, the U.S. and India can both have levels of consumption that are superior to those attainable on their production possibilities frontiers. The U.S. can move from point A on its trading possibilities frontier to