1、开放经济的宏观经济学：基本概念开放经济的宏观经济学：基本概念Open-Economy Macroeconomics:Basic Concepts第第25章章 Chapter 25（对应教材（对应教材31章）章）开放经济与封闭经济开放经济与封闭经济Open and Closed Economiesu封闭经济是指没有和世界其他经济相互交易封闭经济是指没有和世界其他经济相互交易的经济。的经济。A closed economy is one that does not interact with other economies in the world.u没有出口，没有进口，也没有资本流动。没有出口，
2、没有进口，也没有资本流动。There are no exports,no imports,and no capital flows.开放经济与封闭经济开放经济与封闭经济Open and Closed Economies开放经济是与世界其他经济开放经济是与世界其他经济自由交易的经济。自由交易的经济。An open economy is one that interacts freely with other economies around the world.开放经济开放经济An Open Economyu开放经济通过两种方式和其他一些国家交易。开放经济通过两种方式和其他一些国家交易。An o
3、pen economy interacts with other countries in two ways.u在世界产品市场购买与出售商品与劳务在世界产品市场购买与出售商品与劳务 It buys and sells goods and services in world product markets.u在世界金融市场购买与出售资本资产。在世界金融市场购买与出售资本资产。It buys and sells capital assets in world financial markets.开放经济开放经济An Open Economyu美国经济具有非常大的开发性，它进口与出口美国经济具有非常
4、大的开发性，它进口与出口大量的产品与劳务。大量的产品与劳务。The U.S.is a very large and open economy it imports and exports huge quantities of goods and services.u在过去的四十多年，国际贸易与金融变得越来在过去的四十多年，国际贸易与金融变得越来越重要。越重要。Over the past four decades,international trade and finance have become increasingly important.物品的流动：出口，进口，净出口物品的流动：出口，进
5、口，净出口The Flow of Goods:Exports,Imports,Net Exportsu出口出口是在国外销售而在国内生产的物品与是在国外销售而在国内生产的物品与劳务。劳务。Exports are domestically produced goods and services that are sold abroad.u进口进口是在国内销售而由国外生产的物品与是在国内销售而由国外生产的物品与劳务。劳务。Imports are foreign produced goods and services that are sold domestically.物品的流动：出口，进口，净出口
6、物品的流动：出口，进口，净出口The Flow of Goods:Exports,Imports,Net Exportsu净出口（净出口（NX）是一个国家出口值与进口之的是一个国家出口值与进口之的差额。差额。Net exports(NX)are the value of a nations exports minus the value of its imports.u净出口也叫净出口也叫贸易余额。贸易余额。Net exports are also called the trade balance.物品的流动：出口，进口，净出口物品的流动：出口，进口，净出口The Flow of Goods:
7、Exports,Imports,Net Exportsu贸易赤字是净出口贸易赤字是净出口(NX)为负的情况。为负的情况。A trade deficit is a situation in which net exports(NX)are negative.Imports Exports u贸易盈余是净出口贸易盈余是净出口(NX)为正的情况。为正的情况。A trade surplus is a situation in which net exports(NX)are positive.Exports Importsu贸易平衡贸易平衡是指净出口为零，即出口与进口完全相等是指净出口为零，即出口与进
8、口完全相等 Balanced trade refers to when net exports are zero exports and imports are exactly equal.净出口的影响因素净出口的影响因素Factors That Affect Net Exportsu消费者对国内与国外物品的嗜好。消费者对国内与国外物品的嗜好。The tastes of consumers for domestic and foreign goods.u国内外物品的价格国内外物品的价格 The prices of goods at home and abroad.u人们可以用于国内通货与国外通
9、货的汇率人们可以用于国内通货与国外通货的汇率 The exchange rates at which people can use domestic currency to buy foreign currencies.净出口的影响因素净出口的影响因素Factors That Affect Net Exportsu国内外消费者的收入国内外消费者的收入 The incomes of consumers at home and abroad.u从一国到另一国运送物品的成本。从一国到另一国运送物品的成本。The costs of transporting goods from country to
10、country.u政府对国际贸易的政策。政府对国际贸易的政策。The policies of the government toward international trade.Percentof GDP出口出口进口进口0510151950195519601965197019751980199019851995美国经济的国际化美国经济的国际化The Internationalization of the U.S.Economy1995资本的流动：资本净流出资本的流动：资本净流出The Flow of Capital:Net Foreign Investmentu资本净流出（或国内净投资）资本净
11、流出（或国内净投资）是指本国居民购是指本国居民购买的外国资产减去外国人购买的国内资产。买的外国资产减去外国人购买的国内资产。Net foreign investment refers to the purchase of foreign assets by domestic residents minus the purchase of domestic assets by foreigners.u美国居民购买丰田公司的故片，而墨西哥人购买福美国居民购买丰田公司的故片，而墨西哥人购买福特汽车公司的股票。特汽车公司的股票。A U.S.resident buys stock in the Toyo
12、ta corporation and a Mexican buys stock in the Ford Motor corporation.影响资本净流出的因素影响资本净流出的因素Variables that Influence Net Foreign Investmentu外国资产得到的实际利率外国资产得到的实际利率 The real interest rates being paid on foreign assets.u国内资产得到的实际利率国内资产得到的实际利率 The real interest rates being paid on domestic assets.u持有国外资产可
13、以察觉到的经济与政治风险持有国外资产可以察觉到的经济与政治风险 The perceived economic and political risks of holding assets abroad.u影响国外拥有国内资产的政府政策影响国外拥有国内资产的政府政策 The government policies that affect foreign ownership of domestic assets.净出后与资本净流出的相等净出后与资本净流出的相等The Equality of Net Exports and Net Foreign Investmentu净出口净出口(NX)与资本净流出
14、与资本净流出(NFI)是密切相关的。是密切相关的。Net exports(NX)and net foreign investment(NFI)are closely linked.u从整个经济来看，从整个经济来看，NX与与NFI（NCO）应该互相应该互相平衡。平衡。For an economy as a whole,NX and NFI must balance each other so that:NFI（NCO）=NXu这个等式是成立的，是因为影响这个方程式一方的每这个等式是成立的，是因为影响这个方程式一方的每一次交易也必然完全等量地影响另一方。一次交易也必然完全等量地影响另一方。This
15、 holds true because every transaction that affects one side must also affect the other side by the same amount.储蓄、投资及其与国际流动的关系储蓄、投资及其与国际流动的关系Saving,Investment,and Their Relationship to the International Flowsu净出口是国内生产总值（净出口是国内生产总值（Y）的一部分。）的一部分。Net exports is a component of GDP:Y=C+I+G+NXu国民储蓄是在支付了限期
16、消费和政府购买之后国民储蓄是在支付了限期消费和政府购买之后剩下的国民收入。剩下的国民收入。National saving is the income of the nation that is left after paying for current consumption and government purchases:Y-C-G=I+NX储蓄、投资及其与国际流动的关系储蓄、投资及其与国际流动的关系Saving,Investment,and Their Relationship to the International Flowsu国民储蓄（国民储蓄（S）等于）等于Y-C-G，所以：，所
17、以：uNational saving(S)equals Y-C-G so:S=I+NXor国内投资国内投资 资本净流出资本净流出储蓄储蓄 =+(a)国民储蓄与国内投资国民储蓄与国内投资(GDP的百分比的百分比)Percentof GDP2018161412 101965199519901985198019751970National savingDomestic investment国民储蓄，国内投资与资本净流出国民储蓄，国内投资与资本净流出National Saving,Domestic Investment,and Net Foreign Investment2000(b)资本净流出资本净
18、流出(GDP的百分比的百分比)1965199519901985198019751970Percentof GDP4-4-3-2-10123Net foreigninvestment国民储蓄，国内投资与资本净流出国民储蓄，国内投资与资本净流出National Saving,Domestic Investment,and Net Foreign Investment2000实际与名义汇率实际与名义汇率Real and Nominal Exchange Ratesu国际交易受到其国际价格的影响。国际交易受到其国际价格的影响。International transactions are influen
19、ced by international prices.u两种最重要的国际价格是名义汇率与实两种最重要的国际价格是名义汇率与实际汇率。际汇率。The two most important international prices are the nominal exchange rate and the real exchange rate.名义汇率名义汇率Nominal Exchange Ratesu名义汇率名义汇率是一个人可以用一国货币交换是一个人可以用一国货币交换另一国货币的比率。另一国货币的比率。The nominal exchange rate is the rate at whic
20、h a person can trade the currency of one country for the currency of another.名义汇率名义汇率Nominal Exchange Ratesu名义汇率可以用两种方法表示：名义汇率可以用两种方法表示：The nominal exchange rate is expressed in two ways:u每美元外国货币的单位。每美元外国货币的单位。In units of foreign currency per one U.S.dollar.u每单位外国货币的美元单位。每单位外国货币的美元单位。And in units of
21、 U.S.dollars per one unit of the foreign currency.名义汇率名义汇率Nominal Exchange Ratesu假定日元与美元的汇率是假定日元与美元的汇率是80日元对日元对1美元：美元：Assume the exchange rate between the Japanese yen and U.S.dollar is 80 yen to one dollar.u1美元贸易对应美元贸易对应80日元。日元。One U.S.dollar trades for eighty yen.u一日元的贸易对应一日元的贸易对应0.0125美元。美元。One y
22、en trades for 1/80(=0.0125)of a dollar.名义汇率名义汇率Nominal Exchange Ratesu假如假如1美元买更多的外国货币，这种变动就美元买更多的外国货币，这种变动就称为美元升值。称为美元升值。If a dollar buys more foreign currency,there is an appreciation of the dollar.u假如假如1美元买更少的外国货币，这种变动就美元买更少的外国货币，这种变动就称为美元贬值。称为美元贬值。If it buys less there is a depreciation of the do
23、llar.实际汇率实际汇率Real Exchange Rates实际汇率是一个人可以用一国的物实际汇率是一个人可以用一国的物品与劳务与另一国的物品与劳务交品与劳务与另一国的物品与劳务交易的比率。易的比率。The real exchange rate is the rate at which a person can trade the goods and services of one country for the goods and services of another.实际汇率实际汇率Real Exchange Ratesu实际汇率可以通过国内经济中国内商品实际汇率可以通过国内经济中国
24、内商品与国外商品的价格对比表示。与国外商品的价格对比表示。The real exchange rate compares the prices of domestic goods and foreign goods in the domestic economy.u假如德国啤酒是美国啤酒的两倍，实际汇率是一瓶假如德国啤酒是美国啤酒的两倍，实际汇率是一瓶美国啤酒对应美国啤酒对应1/2瓶美国啤酒。瓶美国啤酒。If a case of German beer is twice as expensive as American beer,the real exchange rate is 1/2 ca
25、se of German beer per case of American beer.实际汇率实际汇率Real Exchange Rates实际汇率取决于名义汇率和用本国货币实际汇率取决于名义汇率和用本国货币衡量的两国物品价格。衡量的两国物品价格。The real exchange rate depends on the nominal exchange rate and the prices of goods in the two countries measured in local currencies.实际汇率实际汇率Real Exchange Ratesu实际汇率是决定一国进口和出
26、口多实际汇率是决定一国进口和出口多少的关键因素。少的关键因素。The real exchange rate is a key determinant of how much a country exports and imports.国外价格国内价格名义汇率 x 实际汇率实际汇率实际汇率实际汇率Real Exchange Ratesu美元真实汇率的下降意味着美国产品比外国产品美元真实汇率的下降意味着美国产品比外国产品更便宜。更便宜。A depreciation(fall)in the U.S.real exchange rate means that U.S.goods have become
27、 cheaper relative to foreign goods.u这将刺激国内外消费者购买更多美国产品而更少这将刺激国内外消费者购买更多美国产品而更少购买其他国家的产品。购买其他国家的产品。This encourages consumers both at home and abroad to buy more U.S.goods and fewer goods from other countries.实际汇率实际汇率Real Exchange Ratesu因此，美国出口增加，进口减少，两方面的变因此，美国出口增加，进口减少，两方面的变化增加了美国净出口。化增加了美国净出口。As a
28、result,U.S.exports rise,and U.S.imports fall,and both of these changes raise U.S.net exports.u反过来，美元实际汇率的上升意味着美国产品反过来，美元实际汇率的上升意味着美国产品比对应的国外产品更贵，因此净出口就会下降比对应的国外产品更贵，因此净出口就会下降。Conversely,an appreciation in the U.S.real exchange rate means that U.S.goods have become more expensive compared to foreign
29、goods,so U.S.net exports fall.购买力平价购买力平价Purchasing-Power Parityu购买力评价理论是解释货币汇率变动购买力评价理论是解释货币汇率变动中最简单也得到最广泛接受的理论。中最简单也得到最广泛接受的理论。The purchasing-power parity theory is the simplest and most widely accepted theory explaining the variation of currency exchange rates.购买力平价购买力平价Purchasing-Power Parityu 根据
30、购买力平价理论，任何一种货根据购买力平价理论，任何一种货币的一单位应该能在所有国家买到等币的一单位应该能在所有国家买到等量的物品。量的物品。uAccording to the purchasing-power parity theory,a unit of any given currency should be able to buy the same quantity of goods in all countries.购买力平价的基本逻辑购买力平价的基本逻辑Basic Logic of Purchasing-Power Parityu购买力平价理论根据单一价格规律得出。购买力平价理论根据
31、单一价格规律得出。The theory of purchasing-power parity is based on a principle called the law of one price.u根据单一价格规律，一种产品在所有地方都根据单一价格规律，一种产品在所有地方都应该按照同样的价格出售。应该按照同样的价格出售。According to the law of one price,a good must sell for the same price in all locations.购买力平价的基本逻辑购买力平价的基本逻辑Basic Logic of Purchasing-Power
32、 Parityu假如单一价格规律没有体现，就存在未被利用假如单一价格规律没有体现，就存在未被利用的利润机会。的利润机会。If the law of one price were not true,unexploited profit opportunities would exist.u利用在不同市场上价格差的过程被称为套利。利用在不同市场上价格差的过程被称为套利。The process of taking advantage of differences in prices in different markets is called arbitrage.购买力平价的基本逻辑购买力平价的基本
33、逻辑Basic Logic of Purchasing-Power Parityu假如套利出现，两个市场的不同价格最终将会趋假如套利出现，两个市场的不同价格最终将会趋于相等。于相等。If arbitrage occurs,eventually prices that differed in two markets would necessarily converge.u根据购买力平价理论，一种货币在每个国家都应根据购买力平价理论，一种货币在每个国家都应该有相同的购买力，汇率的变动促使其的实现。该有相同的购买力，汇率的变动促使其的实现。According to the theory of pur
34、chasing-power parity,a currency must have the same purchasing power in all countries and exchange rates move to ensure that.购买力平价理论的政策含义购买力平价理论的政策含义Implications of Purchasing-Power Parityu假如美元在国内外的购买力相同，汇率就假如美元在国内外的购买力相同，汇率就不会发生变化。不会发生变化。If the purchasing power of the dollar is always the same at ho
35、me and abroad,then the exchange rate cannot change.u两国货币之间的名义汇率应该反映这两个国两国货币之间的名义汇率应该反映这两个国家物价水平差别。家物价水平差别。The nominal exchange rate between the currencies of two countries must reflect the different price levels in those countries.购买力平价理论的政策含义购买力平价理论的政策含义Implications of Purchasing-Power Parityu当中央银行
36、发行了大量货币时，无论根据它当中央银行发行了大量货币时，无论根据它能买到的物品与劳务，它是根据他能购买到能买到的物品与劳务，它是根据他能购买到的其他货币，这种货币的价值减少了。的其他货币，这种货币的价值减少了。When the central bank prints large quantities of money,the money loses value both in terms of the goods and services it can buy and in terms of the amount of other currencies it can buy.10,000,00
37、0,0001,000,000,000,000,000100,0001.00001.000000000119211922192319241925Exchange rate货币供给货币供给物价水平物价水平指数指数1921年年1月月=100德国超速通货膨胀时的货币、物价与名义汇率德国超速通货膨胀时的货币、物价与名义汇率Money,Prices,and the Nominal Exchange Rate During the German Hyperinflation购买力平价理论的局限性购买力平价理论的局限性Limitations of Purchasing-Power Parityu许多产品不容易
38、在国家之间贸易或运输许多产品不容易在国家之间贸易或运输。Many goods are not easily traded or shipped from one country to another.u可贸易的产品在不同的国家生产，并不可贸易的产品在不同的国家生产，并不总能完全替代。总能完全替代。Tradable goods are not always perfect substitutes when they are produced in different countries.总结总结Summaryu净出口是在国外销售的国内生产的物品与劳净出口是在国外销售的国内生产的物品与劳务价值减在
39、国内销售的国外产品与劳务的价务价值减在国内销售的国外产品与劳务的价值。值。Net exports are the value of domestic goods and services sold abroad minus the value of foreign goods and services sold domestically.u资本净流出是国内居民获得的国外资产减外资本净流出是国内居民获得的国外资产减外国人获得的国内资产。国人获得的国内资产。Net foreign investment is the acquisition of foreign assets by domestic
40、 residents minus the acquisition of domestic assets by foreigners.总结总结Summaryu一个经济的资本净流出总是等于其净出口。一个经济的资本净流出总是等于其净出口。An economys net foreign investment always equals its net exports.u一个经济的储蓄既可以用于为国内投资筹资一个经济的储蓄既可以用于为国内投资筹资，也可以用于购买国外资产。，也可以用于购买国外资产。An economys saving can be used to either finance inves
41、tment at home or to buy assets abroad.总结总结Summaryu名义汇率是两国货币的相对价格。名义汇率是两国货币的相对价格。The nominal exchange rate is the relative price of the currency of two countries.u实际汇率是两国物品与劳务的相对价格。实际汇率是两国物品与劳务的相对价格。The real exchange rate is the relative price of the goods and services of two countries.总结总结Summaryu当名
42、义汇率变动致使每美元能购买更多外国货当名义汇率变动致使每美元能购买更多外国货币时，可以说美元升值或坚挺。币时，可以说美元升值或坚挺。When the nominal exchange rate changes so that each dollar buys more foreign currency,the dollar is said to appreciate or strengthen.u当名义汇率变动致使每美元只能购买较少外国当名义汇率变动致使每美元只能购买较少外国货币时，可以说美元贬值或疲软。货币时，可以说美元贬值或疲软。When the nominal exchange rate
43、 changes so that each dollar buys less foreign currency,the dollar is said to depreciate or weaken.总结总结Summaryu根据购买力平价理论，一单位任何一国货币应根据购买力平价理论，一单位任何一国货币应该能在所有国家购买等量的物品。该能在所有国家购买等量的物品。According to the theory or purchasing-power parity,a unit of currency should buy the same quantity of goods in all countries.u两国之间的名义汇率应该反映这两个国家的物两国之间的名义汇率应该反映这两个国家的物价水平。价水平。The nominal exchange rate between the currencies of two countries should reflect the countries price levels in those countries.
