1、Slides prepared by Thomas BishopCopyright 2009 Pearson Addison-Wesley. All rights reserved. Chapter 3 Labor Productivity, Comparative Advantage and International Trade: The Ricardian Model 3-2 Preview The Mercantilists Views on Trade Trade Based on Absolute Advantage: Adam Smith Trade Based on Compa
2、rative Advantage: David Ricardo Opportunity costs and comparative advantage A One Factor Ricardian Model Gains from trade Empirical evidence on Ricardian Model A Guiding Case 在每年情人节时，美国对玫瑰有很高的需求，但是在 冬天美国种植玫瑰比较困难，一方面需要加热的温室 ，另一方面需要投入更多的劳动力和资本。相反，同 样的时间，南美生产玫瑰的成本就很低，但是南美由 于技术和资本的限制，生产计算机的成本却很高。假 定美国生产
3、100支玫瑰的资源可以生产10台计算机，南 美生产100支玫瑰的资源可以生产3台计算机。通过简 单计算就能发现，如果两个国家都专业化生产自己生 产效率高的产品的话美国生产计算机，南美生产 玫瑰，并相互贸易，二者都可以在贸易中获利。 3-4 Basic Questions What is the basis for trade? What is the pattern of trade? What are gains from trade? The Mercantilists Views on Trade (重商主义的贸易思想) 3-5 Mercantilism(重商主义) Economic p
4、hilosophy in 15th and 18th centuries. 早期重商主义以早期重商主义以“货币差额论货币差额论”为中心，其代表人物为中心，其代表人物 是英国的威廉是英国的威廉斯塔福（斯塔福（William Stafford，1554-1612）。）。 晚期重商主义以晚期重商主义以“贸易差额论贸易差额论”为中心，代表人物是为中心，代表人物是 英国的托马斯英国的托马斯孟（孟（Thomas Mun，1571-1641）。）。 Belief that nation could become rich and powerful only by exporting more than it
5、 imported. The Mercantilists Views on Trade Trade surpluses brought inflow of gold and silver. Trade policy was to encourage exports and restrict imports(贸易政策是奖出限入). One nation gained only at the expense of another (zero-sum game，零和博弈). -Do you agree? The Mercantilists Views on Trade (cont.) Mercant
6、ilists measured wealth of a nation by stock of precious metals it possessed.(重商主 义这以一个国家拥有的贵金属作为衡量其财富 的象征。) Today, we measure wealth of a nation by its stock of human, man-made and natural resources available for producing goods and services. The greater the stock of resources, the greater the flow
7、of goods and services to satisfy human wants, and the higher the standard of living. Discussion How to evaluate the Mercantilism? Why Chinas government were being bored with the increasing trade surplus in recent years? 3-9 2005-2013中国的贸易顺差和外汇储备（单位：亿美元）中国的贸易顺差和外汇储备（单位：亿美元） 20052006200720082009201020
8、1120122013 贸易顺差贸易顺差 102017752618298119571815 155123112598 外汇储备外汇储备 81891066315283194602399228473 318113311638395 Trade Based on Absolute Advantage(绝对优势): The Smith Model 3-10 Absolute Advantage and Trade Adam Smith(亚当斯密). Inquiry into the Nature and Causes of Wealth of Nations, 1776. A nation has ab
9、solute advantage(绝对优势) over another nation if it can produce a commodity more efficiently. When one nation has absolute advantage in production of a commodity, but an absolute disadvantage with respect to the other nation in a second commodity, both nations can gain by specializing in their absolute
10、 advantage good and exchanging part of the output for the commodity of its absolute disadvantage(绝对劣势). 亚当亚当斯密的自由贸易思想斯密的自由贸易思想 斯密主张自由贸易（交换），认为国际贸易是自 由市场经济的一部分，不应加以任何限制。 斯密认为，国际贸易和国际分工的原因及基础是 各国间存在的劳动生产率和生产成本的绝对差别。 各国应专业化生产并出口具有劳动生产率和生产 成本“绝对优势”的产品，不生产并进口其不具 有“绝对优势”的产品，其结果比自己什么都生 产更有利。 一个别针工厂的例子一个别针工
11、厂的例子 亚当斯密在工业革命的高潮中思考一个问题，为什么一 些国家富有天下，一些国家却一贫如洗?他通过强调劳动 分工与自由市场的作用来回答这个问题。他在国富论 中举了一个别针工厂的例子，用18世纪70年代的手工工 具，1个工人1天能造20个别针。而如果通过劳动分工， 把整个生产过程分解为若干个工人专门从事的工序，第 一个人负责拉铁丝，第二个人负责弄直，第三个人负责 切断，第四个人负责削尖，第五个人负责磨光，然后有 三个人做针帽，再有一个人负责固定，最后再将别针擦 亮并包装。这样，即使同样的手工工具，1个工人一天可 以惊人地完成4800个别针！ 思考：如果没有很大的市场，这种劳动分工能否得到支
12、撑？ 绝对优势的衡量方法：绝对优势的衡量方法： （1）用劳动生产率（Labor Productivity），即用 单位要素投入的产出率来衡量 ： （2）用生产成本（Production Cost），即用生产 一单位产品所需的要素投入数量来衡量 ： L Q j j Lj Q L a An Example Canada is efficient in growing wheat, inefficient in growing bananas. Brazil is efficient in growing bananas, inefficient in growing wheat. Canada h
13、as absolute advantage in wheat, Brazil has absolute advantage in bananas. Mutually beneficial trade can take place if both countries specialize in their absolute advantage. An Example(cont.) CanadaBrazil Wheat (kg/labor hour)61 Banana (kg/labor hour)35 Canada has absolute advantage over Brazil in wh
14、eat. Brazil has absolute advantage over Canada in banana. Canada could specialize in production of wheat, Brazil could specialize in production of banana, and exchange part of the product of its absolute advantage. Both nations can gain from specialization in production and trade. 绝对优势理论的局限性：无法解释绝对先
15、绝对优势理论的局限性：无法解释绝对先 进和绝对落后国家之间的贸易进和绝对落后国家之间的贸易 发达国家和发展中国家的发达国家和发展中国家的 贸易为什么会发生？贸易为什么会发生？ CanadaBrazil Wheat (kg/labor hour)61 Banana (kg/labor hour)42 Trade Based on Comparative Advantage: The Ricardian Model 3-18 Comparative Advantage(比较优势) David Ricardo(大卫李嘉图). On the Principles of Political Econom
16、y and Taxation, 1979. Law of Comparative Advantage Even if one nation is less efficient than (has absolute disadvantage with respect to) the other nation in production of both commodities, there is still a basis for mutually beneficial trade. Of two advantages choose the more, while of two disadvant
17、ages choose the less(两利相权取其重， 两弊相权取其轻). Comparative Advantage: A Numerical Example nBrazil has absolute disadvantage in both goods. nSince Brazil labor is half as productive in Banana but six times less productive in wheat compared to Canada, Brazil has a comparative advantage in Banana. nCanada has
18、 comparative advantage in wheat. CanadaBrazil Wheat (kg/labor hour)61 Banana (kg/labor hour)42 Comparative Advantage and Opportunity Costs The original idea of comparative advantage was based on the labor theory of value: The value or price of a commodity depends exclusively on the amount of labor u
19、sed to produce it. Can use the opportunity cost(机会成本机会成本) theory to explain comparative advantage: The cost of a commodity is the amount of a second commodity that must be given up to release just enough resources to produce one additional unit of the first commodity. 3-22 Comparative Advantage and
20、Opportunity Cost (cont.) A country has a comparative advantage in producing a good if the opportunity cost of producing that good is lower in the country than it is in other countries. (如果一国生产某种 商品的机会成本较低，则在这种商品上具有比 较优势) A country with a comparative advantage in producing a good uses its resources m
21、ost efficiently when it produces that good compared to producing other goods. A measure of comparative advantage Opportunity Cost (机会成本机会成本) Relative Labor Productivity (相对劳动生产率相对劳动生产率) Relative Production Cost (相对生产成本相对生产成本) 3-23 LQB LQA A B A 的劳动生产率产品 的劳动生产率产品 的相对劳动生产率产品 LB LA aB aA A 的要素投入量单位产品 的
22、要素投入量单位产品 的相对成本产品 An example 中美两国的生产可能性中美两国的生产可能性 大米（吨）大米（吨）小麦（吨）小麦（吨） 中国中国10050 美国美国150100 注：中美两国在两种产品生产中各投入100单位劳动力。 中国和美国生产大米和小麦的机会成本中国和美国生产大米和小麦的机会成本 单位产量的劳动投入（生产成本）单位产量的劳动投入（生产成本） 大米大米小麦小麦 中国中国1.0单位劳动单位劳动2.0单位劳动单位劳动 美国美国0.67单位劳动单位劳动1.0单位劳动单位劳动 机会成本机会成本 生产大米的机会成本生产大米的机会成本生产小麦的机会成本生产小麦的机会成本 中国中国0
23、.5吨小麦吨小麦2吨大米吨大米 美国美国0.67吨小麦吨小麦1.5吨大米吨大米 美国在大米和小麦生产上的单位劳动投入都低于中国（美国在大米和小麦生产上的单位劳动投入都低于中国（绝对优势绝对优势），但是），但是 从机会成本来看，中国生产大米的机会成本比美国低（具有从机会成本来看，中国生产大米的机会成本比美国低（具有比较优势比较优势），）， 美国生产小麦的机会成本比中国低（具有比较优势）。因此，中国应专业美国生产小麦的机会成本比中国低（具有比较优势）。因此，中国应专业 化生产并出口大米，美国应专业化生产并出口小麦。化生产并出口大米，美国应专业化生产并出口小麦。 中国和美国的劳动生产率和相对劳动生产
24、率中国和美国的劳动生产率和相对劳动生产率 劳动生产率劳动生产率 大米大米小麦小麦 中国中国1.00.5 美国美国1.51.0 相对劳动生产率相对劳动生产率 大米大米/小麦小麦小麦小麦/大米大米 中国中国20.5 美国美国1.50.67 美国在大米和小麦生产上的劳动生产率都高于中国（美国在大米和小麦生产上的劳动生产率都高于中国（绝对优势绝对优势），但是从相），但是从相 对劳动生产率来看，中国生产大米的相对劳动生产率比美国高（具有对劳动生产率来看，中国生产大米的相对劳动生产率比美国高（具有比较优比较优 势势），美国生产小麦的相对劳动生产率比中国高（具有比较优势）。因此，），美国生产小麦的相对劳动生
25、产率比中国高（具有比较优势）。因此， 中国应专业化生产并出口大米，美国应专业化生产并出口小麦。中国应专业化生产并出口大米，美国应专业化生产并出口小麦。 3-27 A One-Factor Ricardian Model The simplifying assumptions in Ricardian model(221 model): Only two countries are modeled: domestic and foreign. Only two goods are important for production and consumption: wine and cheese.
26、 Only one resource, labor, is important for production. The supply of labor services in each country is constant. Labor productivity varies across countries, usually due to differences in technology, but labor productivity in each country is constant across time. 3-28 Production Possibilities(生产可能性)
27、 The production possibility frontier (PPF) of an economy shows the maximum amount of a goods that can be produced for a fixed amount of resources. If QC represents the quantity of cheese produced and QW represents the quantity of wine produced, then the production possibility frontier of the domesti
28、c economy has the equation: aLCQC + aLWQW = L Total units of wine production Labor required for each unit of cheese production Total units of cheese production Labor required for each unit of wine production Total amount of labor resources 3-29 Fig. 3-1: Homes Production Possibility Frontier The opp
29、ortunity cost is equal to the absolute value of the slope of the PPF (aLC /aLW ), and it is constant when unit labor requirements are constant. 3-30 Production Possibilities (cont.) In general, the amount of the domestic economys production is defined by aLCQC + aLWQW L This describes what an econom
30、y can produce, but to determine what the economy does produce, we must determine the prices of goods.（生产可能性边界表示一个国家能够生产的 不同产品组合，但是要确定一个国家究竟生产什么， 生产多少，还需要知道产品的价格和生产成本，尤其 是两种产品的相对价格。） 3-31 Production, Prices and Wages Let PC be the price of cheese and PW be the price of wine. Because of competition（竞争
31、经济中不存在利润）, hourly wages of cheese makers are equal to the market value of the cheese produced in an hour(奶酪部门每小时工资 等于1个工人在1小时内创造的价值): PC /aLC hourly wages of wine makers are equal to the market value of the wine produced in an hour: PW /aLW 当一国奶酪的相对价格高于它的机会成本时，该国就 专门生产奶酪；当奶酪的相对价格低于它的机会成本 时，该国就专门生产葡萄
32、酒。 当奶酪的相对价格等于它的机会成本时，本国两种产 品都生产，此时没有国际贸易。 3-32 Trade in the Ricardian Model Suppose the domestic country is more efficient in wine and cheese production. It has an absolute advantage in all production: its unit labor requirements for wine and cheese production are lower than those in the foreign cou
33、ntry: aLC a*LC and aLW a*LW The domestic country has a comparative advantage in cheese production: its opportunity cost of producing cheese is lower than it is in the foreign country. aLC /aLW a*LC /a*LW 3-33 Trade in the Ricardian Model (cont.) The domestic country will export cheese, and the forei
34、gn country will export wine. Eventually, the domestic relative price of cheese will be equal to the foreign relative price of cheese. （最终两国商品的相对价格 相等，为什么？） What determining the relative price after trade? 3-34 Determining the Relative Price After Trade 国际贸易的结果是， 一种贸易产品 （奶酪）对另一种 产品（葡萄酒） 的相对价格位于贸 易前两国
35、的相对价 格之间。 3-35 Gains From Trade Domestic workers earn a higher income from cheese production because the relative price of cheese increases with trade. Foreign workers earn a higher income from wine production because the relative price of cheese decreases with trade (making cheese cheaper) and the
36、relative price of wine increases with trade. With trade, consumption in each country is expanded because world production is expanded when each country specializes in producing the good in which it has a comparative advantage. Without trade, consumption is restricted to what is produced. 3-36 Gains
37、From Trade (cont.) Gains from trade come from specializing(专业化) in the type of production which uses resources most efficiently, and using the income generated from that production to buy the goods and services that countries desire. where “using resources most efficiently” means producing a good in
38、 which a country has a comparative advantage. Think of trade as an indirect method of production or a new technology that converts cheese into wine or vice versa. This indirect method of “producing” a gallon of wine is a more efficient method than direct production.(这种间 接生产方式比直接生产效率更高) 3-37 A Numeri
39、cal Example aLC /aLW = 1/2 a*LC /a*LW = 2 Unit labor requirements for domestic and foreign countries (单位产品的劳动投入) CheeseWine DomesticaLC = 1 hour/kgaLW = 2 hours/L Foreigna*LC = 6 hours/kga*LC = 3 hours/L 3-38 A Numerical Example (cont.) The domestic country is more efficient in both industries, but
40、it has a comparative advantage only in cheese production. The foreign country is less efficient in both industries, but it has a comparative advantage in wine production. Quick quiz: what is the domestic countrys opportunity cost of producing wine? what is its opportunity cost of producing cheese? 3
41、-39 A Numerical Example (cont.) With trade, the equilibrium relative price of cheese must be between aLC /aLW = 1/2 and a*LC /a*LW = 2 (Why?) Suppose that PC /PW = 1 in equilibrium. In words, one kg of cheese trades for one liter of wine. 3-40 A Numerical Example (cont.) If the domestic country does
42、 not trade, it can use one hour of labor to produce 1/aLW = 1/2 liter of wine. If the domestic country does trade, it can use one hour of labor to produce 1/aLC = 1 kg of cheese, sell this amount to the foreign country at current prices to obtain 1 liter of wine. 本国用出口奶酪换取葡萄酒的方式“生产”葡萄酒， 比本国直接生产葡萄酒的效
43、率高。 3-41 A Numerical Example (cont.) If the foreign country does not trade, it can use one hour of labor to produce 1/a*LC = 1/6 kg of cheese. If the foreign country does trade, it can use one hour of labor to produce 1/a*LW = 1/3 liter of wine, sell this amount to the domestic country at current pr
44、ices to obtain 1/3 kg of cheese. 外国用出口葡萄酒换取奶酪的方式“生产”奶酪，比 自己直接生产奶酪的效率高。 In this example, each country can use labor twice as efficiently to trade for what it needs instead of production its imports for itself(贸易开放后，各国的劳 动生产效率比自己生产进口商品时提高了一倍). 3-42 Empirical Evidence(经验证据) Do countries export those go
45、ods in which their productivity is relatively high?(一个国家出口的 是劳动生产率较高的商品吗？) The ratio of U.S. to British exports in 1951 compared to the ratio of U.S. to British labor productivity in 26 manufacturing industries suggests yes. At this time the U.S. had an absolute advantage in all 26 industries, yet t
46、he ratio of exports was low in the least productive sectors of the U.S. 3-43 Fig. 3-6: Productivity and Exports 根据比较优势理论，美国 某个产业的相对劳动生产 率较高，美国就比英国更 有可能出口那种产品。 图3-6表明，美国所有26个 制造业的劳动生产率都要 高于英国，但不是每个行 业的出口都大于英国，英 国有12个行业的产业出口 大于美国。 3-44 Table 3-4 China versus Germany, 1995 1995年中国制造业的劳动生产率只是德国的5.2%，制造业产量是 德国的71.6%，中国制造业总体出口水平较低。但是，制造业中的 服装行业的劳动力生产率相对较高，是德国的19.7%，所以该行业 的总产出水平较高，是德国的8倍。 Case Study: Outsourcing(外包) 外包兴起的原因？外包兴起的原因？ 外包的主要经济学原理是什么？外包的主要经济学原理是什么？ 外包对发包国和承接国会产生什么样的外包对发包国和承接国会产生什么样的 影响？影响？ 中国参与国际外包有哪些比较优势？中国参与国际外包有哪些比较优势？ 3-45
