宏观经济学-课后思考题答案_史蒂芬威廉森013

第二部分课后习题第1篇导论和衡量问题第1章导论一、复习题1．宏观经济学的主要鲜明特征是什么？答：（1）宏观经济学的研究对象是众多经济主体的行为。

它关注的是消费者和企业的总体行为、政府的行为、单个国家的经济活动总水平、各国间的经济影响，以及财政政策和货币政策的效应。

（2）宏观经济学侧重于总量研究，强调的问题主要是长期增长和经济周期。

其研究的具体内容包括：①持续经济增长的动力；②经济增长是否有极限；③政府应该如何改变经济增长率，促进经济增长；④经济周期的原因；⑤经济增长在大萧条和第二次世界大战期间发生的剧烈波动是否会重现；⑥政府是否应该采取行动以熨平经济周期。

2．宏观经济学与微观经济学有何异同？答：（1）宏观经济学与微观经济学的联系20世纪70年代以来，微观经济学家与宏观经济学家都在使用非常相似的研究工具。

宏观经济学家用来描述消费者与企业的行为、目标与约束，以及它们之间如何相互影响的经济模型，是根据微观经济学原理建立起来的，而且在分析这些模型和拟合数据时通常都用微观经济学家所用的方法。

宏观经济分析建立在微观经济学原理基础之上。

（2）宏观经济学与微观经济学的区别①研究方法不同微观经济学家侧重个量分析，宏观经济学侧重于总量研究。

②研究内容不同微观经济学研究单个家庭和企业的行为。

因为经济作为一个整体是由许多家庭与企业组成的，在总体水平上的相互影响是单个家庭和企业决策的结果。

宏观经济学有别于微观经济学，因为它涉及的是所有经济主体的选择对经济的总影响，而不是单个消费者或企业的选择对经济的影响，它强调的问题主要是长期增长和经济周期。

3．2011年的普通美国人比1900年的普通美国人富多少？答：2011年的普通的美国人比1900年的普通美国人平均来说富近8倍。

实际人均GDP 是衡量一国居民平均收入水平的指标。

1900年，一个美国人的平均收入是4793美元（以2005年美元计），2011年增加到42733美元（以2005年美元计）。

Macroeconomics(Tenth Edition)Rudiger Dornbusch, Stanley Fisher, Richard StartsCHAPTER 1 INTRODUCTIONConceptual Problemsing the aggregate supply-aggregate demand model explain how output and price are determined. Will output vary or stay fixed in the long run? Suppose the aggregate demand curve were to remain fixed: what can we infer about the behavior of prices over time?Answer:The way output and prices are determined in the aggregate can be analyzed most easily using the AD-AS model; however, we have to determine first which time frame we have in mind.The vertical AS-curve describes the very long run and output is determined by aggregate supply alone while the price level is determined by the level of aggregated demand relative to the output the economy can supply.The horizontal AS-curve describes the very short run and output is determined by aggregate demand alone while the price level is fixed and unaffected by changes in output.The upward-sloping AS-curve describes the medium run and fluctuations in aggregate supply or aggregate demand can determine actual output and the price level under the assumption that productive capacity is given.The AD-AS framework is a very simplified representation of the real world that cannot describe the behavior of all people and enterprises in an economy. In this framework, the effects of changes in aggregate demand on output and prices depend largely on the slope of the AS-curve. We should keep in mind that the long-run AS-curve tends to shift to the right from year to year as potential output tends to grow. Therefore, even in the unlikely event that the AD-curve remains fixed, the price level would change, that is, decline over time.Technical Problems1.Suppose that actual output is $120 billion and potential (full-employment) output is $156 billion. What is an output gap in this hypothetical economy? Based on your estimate of the output gap, would you expect the unemployment level to be higher or lower than usual?Answer：The textbook defines the output gap as the difference between actual GDP and potential GDP. Therefore the output gap in this hypothetical economy is -$36 billion. Since actual output falls short of potential output, we should expect the unemployment rate to be higher than usual.Chapter 2 National Income AccountingConceptual Problems1.what would happen to GDP if the government hired unemployed workers, who had been receiving amount $TR in unemployment benefits, as government employees and now paid the2.m $TR to do nothing? Explain.Answer:Government transfer payments (TR) do not arise out of any production activity and are thus not counted in the value of GDP. If the government hired the people who receive transfer payments, then their wages would be counted as part of government purchases (G), which is counted in GDP. Therefore GDP would rise even if these workers were paid to do nothing, as government purchases are measured on a cost basis.Technical Problems8.Suppose you buy a $100 government bond that is due next year. How much nominal interest will you receive if inflation is 4 percent over the year and the bond promises a real return of 3 percent?Answer:The real interest rate (r) is defined as the nominal interest rate (i) minus the rate of inflation (π). Therefore the nominal interest rate is the real interest rate plus the rate of inflation, ori = r + π = 3% + 4% = 7%.Chapter 3 Growth and AccumulationConceptual2. Can the Solow growth model help to explain the phenomenon of convergence? Answer:The Solow model predicts convergence, that is, countries with the same production function, savings rate, and population growth will eventually reach the same level of income per capita. In other words, a poor country may eventually catch up to a richer one by saving at the same rate and making technological innovations. However, if these countries have different savings rates, they will reach different levels of income per capita, even though their long-term growth rates will be the same.Technical9.For a Cobb-Douglas production function Y=AKθN（1-θ），verify that 1-θis labor’s share of income.[Hint: Labor’s share of income is the piece of income which results from that labor(MP L×N)divided by total income. ]Answer:The Cobb-Douglas production function is defined asY = F(N,K) = AN1-θKθ.The marginal product of labor can then be derived asMPN = (∆Y)/(∆N) = (1 - θ)AN-θKθ = (1 - θ)AN1-θKθ/N = = (1 - θ)(Y/N)==> labor's share of income = [MPN*(N)]/Y = (1 - θ)(Y/N)*[(N)/(Y)] = (1 - θ) Chapter 4 Growth and PolicyConceptual1.What is endogenous growth? How do endogenous growth models differ from the neoclassical models of growth presented in Chapter 3?Answer:Endogenous or self-sustained growth supposedly can be achieved by policies that affect a nation's savings rate and therefore the proportion of GDP that goes towards investment. The neoclassical growth model of Chapter 3 predicted that long-term growth can only be achieved through technological progress and that changes in the savings rate have only transitory effects. The endogenous growth model, however, predicts that countries with a higher savings rate can achieve higher long-term growth and that a nation's government can affect the long-term growth rate by implementing policies that affect the savings rate.2. Why doesn’t the constant marginal poduct of capital assumed in this chapter’s simple model of endogenous growth create a situation in which a single large firm dominaties the economy, as traditional microeconomic reasoning would suggest?Answer:A simple model with constant returns to scale to capital alone implies increasing returns to scale to all factors taken together, which could cause a single large firm to dominate the economy. However, such a model ignores the possibility that external returns to capital exist, in addition to the internal (private) returns. In other words, more investment not only leads to a higher and more efficient capital stock but also to new ideas and new ways of doing things, which can then be copied by others. Therefore, a single firm does not necessarily reap all of the benefits of increased output.Chapter 5 Aggregate supply and demandConceptual2. Explain why the calssical supply curve is vertical. What are the mechanisms that ensure continued full employment of labor in the calssical case?Answer:The classical aggregate supply curve is vertical, since the classical model assumes that nominal wages always adjust immediately to changes in the price level. This implies that the labor market is always in equilibrium and output is always at the full-employment level. If the AD-curve shifts to the right, firms try to increase output by hiring more workers, and they try to attract them by offering higher nominal wages. However, since we are already at full employment, the overall work force does not increase, so firms merely bid up nominal wages. The nominal wage increase is passed on in the form of higher product prices. Since the level of wages and prices will have increased proportionally, the real wage rate and the levels of employment and output will remain unchanged.If there is a decrease in demand, workers are willing to accept lower nominal wages to stay employed. Lower wage costs enable firms to lower their prices, and ultimatelynominal wages and prices decrease proportionally while the real wage rate and the levels of employment and output remain the same.Technical2. Suppose that the government increases spending from G to G’while simultaneously raising taxes in such a way that, at the initial level of output, the budget remains balanced.a. Show the effect of this change on the aggregate demand schedule.b. How does this affect output and the price level in the Keynisian case?c. How does this affect output and the price level in the classical case? Answer:a. According to the balanced budget theorem, a simultaneous and equal increase in government purchases and taxes will shift the AD-curve to the right, as the positive impact of the increase in government spending is greater than the negative impact of the tax increase. But if the AS-curve is upward sloping, then the balanced budget multiplier will be less than one, that is, the increase in output will be less than the increase in government purchases. This occurs because part of the fiscal expansion will be crowded out, that is, the level of private spending will decrease, due to a higher price level, lower real money balances, and the resulting rise in interest rates.b. In the Keynesian case, the AS-curve is horizontal and the price level remains unchanged. There is no real balance effect and therefore income increases more than in 2.a., that is, output increases by the whole shift in the AD-curve. However, the interest rate still increases and therefore the balanced budget multiplier is less than one (but greater than in 2.a.).c. In the classical case, the AS-curve is vertical and the output level remains unchanged. In this case, a shift in the AD-curve leads to a price increase and real money balances decline. Therefore interest rates increase further than in 2.b. or even 2.a., leading to full crowding out of investment. Hence the balanced budget multiplier is zero in the classical case.Chapter 6 Aggregate Supply: Wages, Prices, and UnemploymentConceptual1.Explain how the aggregate supply and Phillips curves are related to each other. Can any information be derived from one that cannot be derived from the other? Answer:The aggregate supply curve and the Phillips curve describe very similar relationships and both curves can be used to analyze the same phenomena. The AS-curve shows a relationship between the price level and the level of output, while the Phillips curve shows a relationship between the inflation and unemployment rates. For example, a movement along the upward-sloping AS-curve depicts an increase in the price level that is associated with an increase in the level of output. But Okun’s law states that changes in output and the rate of unemployment are tightly linked. Therefore, with an increase in the price level (a higher level of inflation) there will be a higher level of output (a lower level of unemployment). Thus the AS-curve is upward sloping while the Phillips curve is downward-sloping. This downward-sloping Phillips curve shifts whenever inflationary expectations change. If one assumes that workers will change their wage demands whenever their inflationary expectations change, one can conclude that a shift in the Phillips curve corresponds to a shift in the upward-sloping AS-curve, since higher wages imply a higher cost of production.The simple AD-AS diagram depicts a static framework, which relates changes in the price level to changes in output supplied or demanded. The Phillips-curve, on the other hand, depicts a dynamic framework in which percentage price changes (the rate of inflation) are related to changes in the unemployment rate. Along the short-run Phillips-curve inflationary expectations are assumed to be constant. If one assumes that price expectations are constant along the upward-sloping AS-curve, the AD-AS framework becomes even more compatible with the Phillips curve framework.CHAPTER 7 THE ANATOMY OF INFLATION AND UNEMPLOYMENT1.Discuss how the following changes would affect the natural (or frictional) rate of unemployment:a. Elimination of unionsb. Increased participation of teenagers in the labor market.Answer:a. It is unclear whether the elimination of unions would actually serve to reduce the natural rate of unemployment. The insider-outsider theory of the labor market suggests that firms bargain with unions (the insiders) and are not much concerned with the unemployed (the outsiders). If unions were eliminated, firms would tend to hire unemployed workers at a lower wage rate, thus reducing the natural unemployment rate. On the other hand, unions tend to preserve stable jobs for their members. Eliminating unions could lead not only to a reduction in bargaining power for labor in wage negotiations but also to an increase in the natural rate of unemployment. If labor unions were eliminated, the wage differentials between unionized and non-unionized workers would disappear and, in the process, some income would be redistributed.b. Increased labor force participation of teenagers would at least initially increase the natural rate of unemployment, since teenagers have a higher frequency of unemployment than older, more experienced workers. However, as more and more teenagers entered the labor force and more good and stable jobs became available to them, the natural rate of unemployment would start to decline again. With more people in the labor force, the supply of labor would be higher and wage rates would be driven down, contributing to wage stagnation.2. The following information is to be used for calculations of the unemployment rate: Suppose there are two major groups, adults and teenagers, with adults divided into men and women. Teenagers account for 10 percent of the labor force; adults account for 90 percent. Women make up 35 percent of the adult labor force. Suppose also that the unemployment rates for these groups are follows: teenagers, 19 percent; men, 7 percent; women, 6 percent.a. Calculate the aggregate unemployment rate.b. What if the share of teenagers in the labor force increases from 10 to 15 percent. How will this affect the aggregate unemployment rate?Answer:a. The aggregate unemployment rate can be calculated by adding the unemployment rates of different groups weighted by their share of the labor force. The data in the problem indicate that teenagers constitute 10% of the labor force. The adult work force (the other 90%) is divided into 35% females and 65% males. Thus we can calculate the overall unemployment rate as:u = (0.1)(0.19) + (0.9)[(0.35)(0.06) + (0.65)(0.07)] = 0.019 + (0.9)(0.021 + 0.0455)= 0.019 + 0.05985 = 0.07885 = 7.9%.b. If the labor force participation rate of teenagers increases to 15%, the overall unemployment rate changes to:u1 = (0.15)(0.19) + (0.85)[(0.35)(0.06) + (0.65)(0.07)]= 0.0285 + (0.85)(0.021 + 0.0455)= 0.0285 + 0.056525 = 0.085025 = 8.5%.CHAPTER 8 POLICY PREVIEW1. How does the Taylor rule help a central bank to set interest rates? How could this rule be adapted if the central bank decided to follow a policy of pure inflation targeting?Answer：The Taylor rule serves as a guide for a central bank on how to set the nominal interest rate in response to current economic conditions. Specifically it states that:i t = r*+ πt+ α*( πt - πt*) + β*[100* (Y t - Y t* )/Y t* ]and suggests that if the inflation rate goes above the inflation target rate π* set by t he central bank or if output goes above the full-employment level Y*, the central bank should raise interest rates . Clearly, the larger the size of the coefficients α and β, the more aggressively the central bank should respond to a change in either inflation or output. If the coefficient β is set to β = 0, the Taylor rule corresponds to strict inflation targeting, in which changes in output are ignored while the central bank still responds to changes in the inflation rate.2. Assume output is currently 1.6% below its full-employment level and the inflation rate is3.5%. Assume further that the central bank has specified that the inflation coefficient is α = 0.5 and that the “natural real interest rate” is assumed to be 2%. At what level should the central bank set the nominal interest rate if it wants to enforce a strict inflation target of 2.5%?Answer：The Taylor rule suggests that a central bank sets the nominal interest rate in the following way:i t = r*+ πt+ α*( πt - πt*) + β*[100* (Y t - Y t* )/Y t* ]Strict inflation targeting suggests that the output coefficient is set to β = 0, so it does not matter how far GDP is below its potential. However, if the current inflation rate is 3.5%, then according to the Taylor rule the central bank should set the nominal interest rate at 6%, sincei t = 2 + 3.5 + 0.5*(3.5 – 2.5) = 5.5 + 05*(1) = 6.。

宏观经济学课后习题答案！！第一章导论1．（1）宏观经济学研究的问题是一个国家整体经济的运行情况以及政府如何运用经济政策来影响国家整体经济的运作。

其核心是国民收入决定理论和就业理论。

（2）宏观经济学研究的是总体经济问题，它涉及经济中商品与劳务的总产出及其增长速度、通货膨胀与失业的程度、经济衰退及其原因、国际收支状况及汇率的变动等。

2．（1）宏观经济学与微观经济学的区别：①研究对象不同。

微观经济学的研究对象是单个经济单位，如家庭、厂商等。

宏观的研究对象则是整个经济，研究整个经济的运行方式与规律，从总量上分析经济问题。

②解决的问题不同。

微观解决的是资源配置问题，即生产什么、如何生产和为谁生产的问题，以实现个体效益的最大化。

宏观则把资源配置作为既定的前提，研究社会范围内的资源利用问题，以实现社会福利的最大化。

③研究方法不同。

微观的研究方法是个量分析，即研究经济变量的单项数值如何决定。

宏观则是总量分析，即对能够反映整个经济运行情况的经济变量的决定、变动及其相互关系进行分析。

④基本假设不同。

微观的基本假设是市场出清（在给定的价格P之下，市场上的意愿供给等于意愿需求，达到均衡状态）、完全理性、充分信息，认为“看不见的手”能自由调节实现资源的优化配置。

宏观则是既定市场机制是不完善的，政府有能力调节经济，通过“看得见的手”纠正市场机制的缺陷。

⑤中心理论不同。

微观的中心理论是价格理论，还包括消费者行为理论、生产理论、分配理论、一般均衡理论、市场理论、产权理论、福利经济学、管理理论等。

宏观的中心理论则是国民收入决定理论，还包括失业与通货膨胀理论、经济周期理论与经济增长理论、开放经济理论等。

（2）宏观经济学与微观经济学的联系：①微观经济分析是宏观经济分析的基础，离开了微观分析这一基础，宏观分析将成为空中楼阁。

②从根本目标上看，宏观经济分析与微观经济分析也是一致的。

③宏观经济学与微观经济学虽然分析的侧重点不同，但二者是不能分开的。

宏观经济学课后习题答案问题1：什么是宏观经济学？它的研究对象是什么？宏观经济学是一门研究整体经济运行的学科。

它关注的是经济中的总体现象和经济运行的规律，包括国民经济的总体规模、增长速度、物价水平、就业水平、物资供求关系等。

宏观经济学的研究对象是整个经济系统，即国民经济的各个部门和各个经济主体之间的关系。

问题2：GDP的定义是什么？它的计算方法有哪些？GDP（国内生产总值）是一个国家或地区在一定时间内所生产的最终产品和服务的总价值。

它可以通过产出法、收入法和支出法进行计算。

•产出法：根据产品的产出量和售价来计算GDP。

主要包括产业增加值、商品增值税和净关税三个部分。

产业增加值是国内企业生产商品和服务所增加的价值，商品增值税是销售商品过程中增加的税费，净关税是进口商品关税减去出口商品的关税。

•收入法：根据国民收入的构成来计算GDP。

主要包括工资、利润、利息和租金等因素。

•支出法：通过对整体需求的衡量来计算GDP。

主要包括消费支出、投资支出、政府支出和净出口四个部分。

问题3：什么是通货膨胀？它有哪些影响因素？通货膨胀是指货币购买力下降，物价水平普遍上涨的现象。

通货膨胀导致货币价值的贬值，影响经济体制和社会生活的稳定。

通货膨胀的影响因素包括：1.需求拉动型通货膨胀：需求过高导致价格上涨。

当居民收入增加，需求上升，商品供不应求时，市场价格会上涨，从而导致通货膨胀。

2.成本推动型通货膨胀：成本上升导致价格上涨。

生产成本的上升，如劳动力成本、原材料成本等，将推动产品价格上涨，从而导致通货膨胀。

3.货币发行过多：当国家通过货币发行扩大经济增长，而没有相应的经济增长，会导致货币供应过剩，从而出现通货膨胀。

4.供给不足：当出现自然灾害、生产能力下降或政策限制等因素，会导致供给不足，进而推动商品价格上涨，引发通货膨胀。

问题4：什么是经济增长？有哪些推动经济增长的因素？经济增长指的是一个国家或地区在一定时间内经济总量的扩大。

1 / 37第1章 导 论1.1 复习笔记一、宏观经济学1．宏观经济学的研究对象宏观经济学的研究对象是众多经济主体的行为。

它关注的是消费者和企业的总体行为、政府的行为、单个国家的经济活动总水平、各国间的经济影响，以及财政政策和货币政策的效应。

2．宏观经济学与微观经济学的联系与区别（1）联系微观经济学家与宏观经济学家都在使用非常相似的研究工具。

宏观经济学家用来描述消费者与企业的行为、目标与约束，以及他们之间如何相互影响的经济模型，是根据微观经济学原理建立起来的，而且在分析这些模型和拟合数据时通常都用微观经济学家所用的方法。

2 / 37（2）区别宏观经济学的研究对象有别于微观经济学，宏观经济学侧重于总量研究，强调的问题主要是长期增长和经济周期。

微观经济学主要针对单个消费者或者企业的行为选择。

二、国内生产总值、经济增长与经济周期1．国内生产总值（gross domestic product ，GDP ）国内生产总值是一国在某一特定时期在境内生产的产品和服务的数量。

GDP 也表示那些对国内产出作出贡献的人挣得的收入总量。

实际GDP 是针对通货膨胀进行调整后的总产出衡量指标。

2．经济增长（long-run growth ）经济增长率是一个国家当年国内生产总值对比往年的增长率。

经济正增长一般被认为是整体经济景气的表现。

长期增长是指一国长期的生产能力和平均生活水平的提高。

3．经济周期（business cycles ）经济周期是指总体经济的短期上下波动，或经济的繁荣与衰退。

3 / 37三、宏观经济模型1．宏观经济模型及其假设宏观经济模型是用来解释长期经济增长、经济周期存在的原因、以及经济政策在宏观经济中应发挥的作用的模型。

确切的说，宏观经济模型的基本构造是用来描述下列特征的：（1）经济中相互影响的消费者与企业。

（2）消费者希望消费的一组商品。

（3）消费者对商品的偏好。

（4）企业生产商品可采用的技术。

（5）可利用的资源。

第一章宏观经济学的科学一、选择题1.下列哪一项不是宏观经济学家研究的主要问题( B )A.经济增长B.供需的价格弹性C.通货膨胀D.充分就业2.下列不正确的是 ( A )A.经济模型是对经济的精确描述B.经济模型是对经济现象的抽象C.经济模型往往是用数学术语说明变量之间的关系D.经济模型有助于解释经济变量3.经济模型要解释的变量是( C )A.内生变量和外生变量B.外生变量C.内生变量D.既不是内生变量也不是外生变量4.存量是( A )A.某个时点现存的经济量值B.某个时点上的流动价值C.流量的固体等价物D.某个时期内发生的经济量值5.下列各项中哪一个属于存量( C )A.国内生产总值B.投资C.失业人数D.人均收入6.宏观经济学的创始人是( C )A.斯密B.马歇尔C.凯恩斯D.萨缪尔森7.在凯恩斯看来,造成资本主义经济萧条的根源是( B )A.资源短缺B.有效需求不足C.资源配置不当D.技术落后8.下列哪一本著作对现代宏观经济学的产生起了最为重要的作用（ C ）。

A.凯恩斯的《货币论》B.马歇尔的《货币、信用与商业》C.凯恩斯的《就业、利息和货币通论》D.亚当.斯密的《国富论》二、名词解释宏观经济学宏观经济学与微观经济学相对，是一种现代的经济分析方法。

它以国民经济总体作为考察对象，研究经济生活中有关总量的决定与变动，解释失业、通货膨胀、经济增长与波动、国际收支及汇率的决定与变动等经济中的宏观整体问题，所以又称之为总量经济学。

宏观经济学的中心和基础是总供给-总需求模型。

具体讲，宏观经济学主要包括总需求理论、总供给理论、失业与通货膨胀理论、经济周期与经济增长理论、开放经济理论宏观经济政策等内容。

对宏观经济问题进行分析与研究的历史十分悠久，但现代意义上的宏观经济学直到20世纪30年代才得以形成和发展起来。

宏观经济学诞生的标志是凯恩斯于1936年出版的《就业、利息和货币通论》。

宏观经济学在20世纪30年代奠定基础，二战后逐步走向成熟并得到广泛应用，60年代后的“滞胀”问题使凯恩斯主义的统治地位受到严重挑战并形成了货币主义、供给学派、理性预期等学派对立争论的局面，90年代新凯恩斯的形成又使国家干预思想占据主流。

宏观经济学-课后思考题答案_史蒂芬威廉森010Chapter 10A Monetary Intertemporal Model: Money, Prices,and Monetary PolicyTeaching GoalsAnalysis of a monetary economy can become quite complex. Modern economies require significant specialization to function well. Such specialization requires a commonly accepted medium of exchange. Money serves this function. Although it matters quite a lot that we have money, the actual quantity of money in circulation is not very important. This fact emerges because the quantity of money is neutral, if not in the very short run, certainly in the long run.In the monetary intertemporal model, changes in the money supply affect the level of prices, but do not otherwise affect economic outcomes; money is neutral. Real factors may also affect the price level. The price level adjusts to keep money demand and money equal. Disturbances that change the equilibrium levels of output and the real interest rate therefore change the price level. Shifts in preferences for money holding also affect the price level.The principle role of monetary policy in the monetary intertemporal model is to control the level of prices.A popular goal of policy is to stabilize the price level in response to shocks to the economy. However, the central bank’s ability to stabilize prices may be compromised if money demand does not behave in a predictable manner. It is also important for policy to set targets and adhere to particular policy rules.Classroom Discussion TopicsThe payments technology has continually advanced over time, but the rate of advance has acceleratedin the era of computer technology. Ask the students for examples of advances in this technology beyond the routine use of cash and the writing of paper checks. Some obvious possibilities include the use of ATMs, computer and telephone banking, the use of prepaid phone cards and other forms of smartcard technologies. Students are also likely to discuss the existence of credit cards and the ever more sophisticated ways to use credit cards and protect against fraud. As one example, there is the use of credit cards to pay for purchases over the Internet. In discussing these possibilities, it is also important to distinguish the payments technology from the proper measurement of the money supply. For example, it is important to distinguish between payment arrangements that are uses of credit, like the use of credit cards, from uses of money, like cash and transaction deposits.Standard macroeconomic analysis, like that of this chapter, emphasizes central banks’ control of the quantity of money in circulation. However, most contemporary discussions of U.S. monetary policy focus on the Federal Reserve’s control of “interest rates.” This chapter offers plenty of opportunities to discuss real life events. For example, discuss the upcoming meeting of the FOMC, what it decides on, what information it uses, and what it may do.102 Williamson ? Macroeconomics, Third EditionIn the monetary intertemporal model, the real interest rate is market determined and cannot be influenced by central bank behavior. Ask the students whether they believe a simplistic view of popular press coverage that seems to refute the notion that the interest rate is market determined. Note the importance of the distinction between the federal funds rate and the sort of real interest rates that motivate saving and investment choices. Is it possible that the Fed adjusts the federal funds rate to more closely resemble other market interest rates? Is it possible to control the nominal interest rate while being unable to influence the real interest rate? Even if the Fed is able to control one very narrowly defined real interest rate, does this mean that models like those in this chapter are not useful descriptions of reality?OutlineI. Functions of MoneyA. Medium of ExchangeB. Store of ValueC. Unit of AccountII. Measuring the Money SupplyA. The Monetary Base1. Currency Outside the Fed2. Depository Institution Deposits at the FedB. M11. Currency Held by the Public2. Traveler’s Checks3. Demand Deposits4. Other Checkable DepositsC. M21. Savings Deposits2. Small-Denomination Time Deposits3. Retail Money Market Mutual FundsD. M31. Large-Denomination Time Deposits2. Institutional Money Market Mutual Funds3. Repurchase Agreements4. EurodollarsIII. Introduction to the Monetary Intertemporal ModelA. The Need for Money1. Single Coincidence of Wants2. Double Coincidence of Wants3. The Cash-in-Advance ModelB. Real and Nominal Interest Rates1. Nominal Bonds2. The Nominal Interest Rate3. The Fisher RelationshipChapter 10 A Monetary Intertemporal Model: Money, Prices, and Monetary Policy 103C. Representative Consumer1. The Cash-in-Advance Constraint2. Banking Service Cost Function3. Optimal Choice of Banking ServicesD. Representative Firm1. The Cash-in-Advance Constraint2. Banking Service Cost Function3. Optimal Choice of Banking Services E. Money and the Government Budget ConstraintIV. Competitive Equilibrium in the Monetary Intertemporal ModelA. Graphical ApparatusB. A Change in the Level of the Money Supply1. Sources of Changes in the Money Supply a. Helicopter Drops: Taxes/Transfersb. Open-Market Operationsc. Seigniorage2. Classical Dichotomy3. Neutrality of MoneyC. A Change in Current Total Factor Productivity1. Real Effects2. Price-Level EffectsD. Shifts in Money Demand1. Sourcesa. Information Technology and Banking Costsb. New Financial Instrumentsc. Government Regulationsd. Perceived Riskiness of Bankse. Changes in Circumstances in the Banking System2. Neutrality vis-à-vis Real Variables3. Price-L evel EffectsE. Monetary Policy Rules1. Under Perfect Information2. Money Supply Targeting3. Nominal Interest Rate Targeting4. The Taylor RuleTextbook Question SolutionsQuestions for Review1. Money serves as a medium of exchange, a store of value, and a unit of account.2. Measures of the money supply include M 0, M 1, and M 2. The monetary base, M 0, includes all currency outside of currency held by the Federal Reserve, and deposits of depositary institutions at the FederalReserve. M 1 includes all currency held by the public (as opposed to bank vaults, the Fed, and the U.S. Treasury), plus travelers’ checks, demand deposits, and other checkable deposits. M 2 includes all of M 1 plus savings deposits, small-denomination time deposits, and retail money market mutual funds.104 Williamson ? Macroeconomics, Third Edition3. Use of money, as opposed to barter in goods or credit, solves the problem of the double coincidenceof wants.4. The nominal rate of interest is approximately equal to the real rate of interest plus the rate of inflation. The exact relationship is:(1)1(1)R r i ++=+ 5. The real rate of return on money is approximately equal to minus the rate of inflation. If we define thereal rate of return on money as ,m r then the exact relationship is:11(1)m r i +=+ 6. The demand for money stems from the desire of consumers to hold money to make purchases. Thosecan be made with a debit card as well, but this is costly, so the consumer decides in advance how much money to withdraw from the bank account. In addition, firms demand money in a similar way so that they can purchase investment goods.7. A permanent, once-and-for-all increase in the money supply has no effect on the real economy. Thatis, money is neutral. The only effect of the increase in the money supply is a permanent, proportionate increase in the price level.8. The government can change the money supply through a temporary tax cut (a helicopter drop), anopen-market operation, and seigniorage.9. The steady-state effects of an increase in the money growth rate include an increase in the rate ofinflation, a reduction in output, a reduction in employment, an increase in the real wage, and anincrease in the nominal interest rate.10. A change in the cost of banking services alters the trade-off between withdrawing money inadvance for purchases and using the debit card. For example, if the cost decreases, thenconsumers and firms will use debit cards more and will withdraw less cash, thus reducing thedemand for money.11. Money demand can increase if incomes rise (households then want to consume more and thus needmore cash, firms want to buy more investment goods and also need more cash), if the nominalinterest rate is lower, as then the opportunity cost of holding money is lower, and if prices are higher, as money demand is formulated in nominal terms. Money demand can be shifted by anything that would alter the cost of banking services, such as: new information technologies that lower the cost of accessing bank accounts, new financial instruments that lower the cost of banking, changes in bank regulation, changes in the perceived risk of banks, and changes in various circumstances in thebanking system.12. As money is neutral in this model, there is no real goal of any relevance, only a nominal goal. Thiswould be to keep inflation low in order to achieve nominal interest rates as low as possible to prevent households and firms to be constrained by the cash-in-advance constraint.13. A monetary policy rule establishes the money supply as a function of observable aggregates. Threeexamples are money supply targeting, nominal interest rate targeting, and the Taylor rule.Chapter 10 A Monetary Intertemporal Model: Money, Prices, and Monetary Policy 105 14. Money supply targeting implies no change of money supply in response to any of the three shifts,leading to price changes and the failure of the price stability goal. Nominal interest rate targeting achieves price stability in response to money demand shocks, but not to output demand or supply shocks. The Taylor Rule has ambiguous consequences with the model we have studied so far. Problems1. Bank service function with fixed cost.(a) This fix cost can be interpreted as the cost of obtaining a debit card, which is independent of thecost of using it.(b) None, as HXis unaffected.(c) It will change the level of money demand, but it has no impact on the slope of money demand oron its shifts in reaction to various circumstances. Indeed, the slope of H(X), or J(R), is still thesame.(d) With a higher D, households make the same choice of banking services, as X must be such thatHX = R, and HXhas not changed. The same applies to the firm. Thus, there is change to thedemand for money and no change to the price level.2. Zero nominal interest rate.(a) Now HX=0, which can only be achieved at X =0.(b) None. Banks are not used at all.(c) Household and firms have no reason to hold any bonds, as their return is the same as money andit costs to use the debit card. So everything is done with cash, and economic agents are notconstrained by the cash-in-advance constraint anymore. However, in order to achieve a zeronominal interest rate, it implies that the inflation rate should be the opposite of the real interestrate, that is negative. This happens only rarely.3. Government spending in the monetary intertemporal model.(a) The real effects of a temporary increase in government spending are the same as those in the realintertemporal model. Output and employment increase, the real interest rate increases, and thereal wage decreases. The new consideration is the effect on the price level. The increase inincome causes money demand to increase. The increase in the real interest rate causes thedemand for money to decrease. With a fixed supply of money, the price level must change tokeep money supply and money demand equal. If the income effect on money demand is stronger, then prices must decrease. If the interest rate effect on money demand is stronger, then pricesmust increase.(b) The real effects of a permanent increase in government spending are the same as those in the realintertemporal model. Output and employment increase, the real interest rate decreases, and thereal wage decreases. In this case the effects of the increase in income and the decrease in theinterest rate both work to increase money demand. In this case, the price level unambiguouslydeclines.4. The real effects of a decrease in the capital stock are the same as those in the real intertemporalmodel. The decrease in K leads to an increase in the real interest rate and a decrease in the real wage.The effects on output and employment are uncertain, although it may be somewhat more likely that output will decrease. A decrease in output along with an increase in the real interest rate both work to decrease money demand. Therefore, the price level would need to increase to keep money supply and money demand equal.5. The current-period real effects of the future increase in total factor productivity are the same as thosepredicted by the real intertemporal model. Output and employment increase, the real wage decreases, and the real interest rate increases. The increase in output increases money demand and the current price level increases.106 Williamson ? Macroeconomics, Third Edition6. The increased presence of ATMs would allow consumers to get by holding less money. Therefore,this disturbance shifts the money demand curve to the left, so the price level would increase to keep money demand and money supply equal.7. Implementing a nominal interest rate rule.(a) This increase in housing construction may arise from household confidence, for example afteran increase in the stock price. Thus we have a temporary increase in money demand with areduction in prices. To lower the nominal interest rate, the monetary authority increases themoney supply, which raises prices to the previous level. Price stabilization is successful.(b) This is like a drop in current total factor productivity with no consequence for future total factorproductivity. Thus, we have a shift to the left of output supply, reducing output and increasingthe real interest rate. Money demand thus drops and prices increase. The monetary authorityshould react by increasing the money supply to reduce the nominal interest rate to the target, but this increases prices further. Prices are then not stable as intended.(c) We learn that total factor productivity is up, and permanently so. This implies that both outputdemand and supply increase, the real interest rate drops, and that money demand shifts to theright leading to lower prices. Under a nominal interest rate target rule, the monetary authoritywould increase the nominal interest rate by reducing the money supply, thus further reducingprices. Prices are then not stable as intended.8. Textbook Chapter 9 discusses the likely effects of a permanent increase in government spending inthe real intertemporal model. As depicted in textbook Figure 9.18, a permanent increase ingovernment spending increases output. This effect works in the direction of increasing the demand for money. In the figure below, the initial price level is P*. With the money supply fixed at M, the price level decreases to ?.P To keep the price level at P*, the money supply must increase to .M If the central bank were pursuing a policy of price-level stabilization, the central bank would find it useful to be able to accurately predict the advent of this disturbance.。

1 / 63第13章 价格和工资具有灵活性的经济周期模型13.1 复习笔记一、经济周期理论概述1．经济周期理论的发展进程（1）凯恩斯主义经济周期模型货币在短期不是中性的，这种非中性是由工资和价格的短期刚性引起的。

在老凯恩斯主义宏观经济模型（20世纪80年代以前的凯恩斯主义模型）中，价格和工资刚性是经济冲击造成总产出波动的形成机制的关键所在。

价格和工资缓慢向其有效值变动的事实，意味着货币政策和财政政策在应对总量冲击时可以发挥稳定经济的作用。

（2）货币主义的经济周期模型货币主义者通常认为，货币政策是比财政政策更有效的稳定工具，但他们对政府政策微调经济的能力持怀疑态度。

一些货币主义者认为，在短期，政策可能是有效的，但非常短。

（3）理性预期学派的经济周期模型2 / 63理性预期革命提出的两大原则是：①宏观经济学模型应建立在微观经济学原理的基础上，即这些模型应以对消费者和企业的偏好、禀赋、技术和最优行为的描述为基础；②包含灵活工资和价格的模型可能是研究宏观经济现象的最富有成效的工具。

2．分析不同经济周期理论的必要性（1）财政政策和货币政策的决策者能够通过经济周期理论，了解左右经济的宏观经济冲击是什么，它对未来总体经济活动有什么影响。

（2）每一种经济周期模型都能确定经济的一个或几个特征及经济对宏观经济冲击作出反应的一些方面。

如果将所有这些特征纳入一个模型中，将无助于认识经济周期行为和政府政策的基本原理。

二、实际经济周期模型实际经济周期模型由芬恩·基德兰德和爱德华·普雷斯科特于20世纪80年代初首创。

1．全要素生产率持续提高的均衡效应假定货币跨期模型中的全要素生产率持续提高，即z 和z ′分别都提高。

（1）全要素生产率z 持续提高的影响3 / 63①当期全要素生产率z 提高会增加每一数量劳动投入量的边际劳动产量，图13-1（a ）中的劳动需求曲线右移，从而导致图13-1（b ）中的产出供给曲线右移。

威廉森《宏观经济学》（第5版）笔记和课后习题详解完整版-精研学习䋞提供免费试用20％资料全国547所院校视频及题库考研全套>视频资料>课后答案>往年真题>职称考试第1章导论1.1复习笔记考点一：宏观经济学★★1宏观经济学的研究对象宏观经济学的研究对象是众多经济主体的经济行为。

它主要关注消费者和企业的总体行为、政府的行为、单个国家的经济活动总水平、各国间的经济影响以及财政政策和货币政策的效应。

2宏观经济学与微观经济学的联系与区别（见表1-1）表1-1宏观经济学与微观经济学的联系与区别考点二：国内生产总值、经济增长与经济周期★★★1国内生产总值（GDP）国内生产总值是指在某一特定时期内，一国在境内生产的产品和服务的数量；也表示那些对国内产出作出贡献的人挣得的收入总量。

区别于名义GDP，实际GDP是针对通货膨胀因素进行调整后的总产出衡量指标。

2经济增长经济增长率是一个国家当年国内生产总值相比往年的增长率。

经济正增长一般就认为整体经济是景气的。

长期增长是指一国长期的生产能力和平均生活水平的提高。

3经济周期经济周期是指总体经济在短期内的上下波动，或经济的繁荣与衰退。

考点三：宏观经济模型★★★1宏观经济模型的特征宏观经济模型是用来解释长期经济增长、经济周期存在的原因以及判断经济政策在宏观经济中应发挥的作用的模型。

准确来说，宏观经济模型的基本构造是用来描述下列特征的：（1）经济中相互影响的消费者与企业。

（2）消费者愿意消费的一组商品。

（3）消费者对商品的偏好。

（4）企业生产商品可采用的技术。

（5）生产时可利用的资源。

2宏观经济模型的假设两个重要假设：①关于消费者与企业的目的。

假定消费者尽可能达到效用最大化，企业尽可能达到利润最大化，即他们在既定的约束下都会竭尽所能；②关于消费者与企业的行为如何实现协调一致。

假定经济处于均衡状态。

在竞争性均衡中，假定商品经由市场买卖，消费者和企业在市场中都是价格接受者。

宏观经济学思考题及参考答案（1）第四章基本概念：潜在GDP，总供给，总需求，AS曲线，AD曲线。

思考题1、宏观经济学的主要目标是什么?写出每个主要目标的简短定义。

请详细解释为什么每一个目标都十分重要。

答:宏观经济学目标主要有四个:充分就业、物价稳定、经济增长和国际收支平衡。

（1)充分就业的本义是指所有资源得到充分利用，目前主要用人力资源作为充分就业的标准;充分就业本不是指百分之百的就业，一般地说充分就业允许的失业范畴为4%。

只有经济实现了充分就业，一国经济才能生产出潜在的GDP，从而使一国拥有更多的收入用于提高一国的福利水平。

（2）物价稳定，即把通胀率维持在低而稳定的水平上。

物价稳定是指一般物价水平(即总物价水平)的稳定;物价稳定并不是指通货膨胀率为零的状态，而是维持一种能为社会所接受的低而稳定的通货膨胀率的经济状态，一般指通货膨胀率为百分之十以下。

物价稳定可以防止经济的剧烈波动，防止各种扭曲对经济造成负面影响。

(3)经济增长是指保持合意的经济增长率。

经济增长是指单纯的生产增长，经济增长率并不是越高越好，经济增长的同时必须带来经济发展;经济增长率一般是用实际国民生产总值的年平均增长率来衡量的。

只有经济不断的增长，才能满足人类无限的欲望。

（4)国际收支平衡是指国际收支既无赤字又无盈余的状态。

国际收支平衡是一国对外经济目标，必须注意和国内目标的配合使用;正确处理国内目标与国际目标的矛盾。

在开放经济下，一国与他国来往日益密切，保持国际收支的基本平衡，才能使一国避免受到他国经济波动带来的负面影响。

3，题略答:a.石油价格大幅度上涨，作为一种不利的供给冲击，将会使增加企业的生产成本，从而使总供给减少，总供给曲线AS将向左上方移动。

b.一项削减国防开支的裁军协议，而与此同时，政府没有采取减税或者增加政府支出的政策，则将减少一国的总需求水平，从而使总需求曲线AD向左下方移动。

c.潜在产出水平的增加，将有效提高一国所能生产出的商品和劳务水平，从而使总供给曲线AS向右下方移动。

Chapter 3Business Cycle MeasurementTeaching GoalsChapter 3 stresses the importance of observation as a foundation for scientific exploration in macroeconomics. Because there are mountains of data measurements about the macroeconomy, we need to begin to organize these data in a way that we can begin to look for regularities in the economy—regularities that we hope to explain. The cornerstone of business cycle analysis is deviations from trend in real GDP. Students must first understand the difference between long-run trends and deviations from trend in real GDP.One of the most exciting things about the study of business cycles is the observation that each of these recurring cycles is not unique. Because successive business cycles are more alike than they are different, we have the hope of providing an explanation of business cycles that can consistently be applied to each new cycle we encounter. These business cycle regularities, the “stylized facts” of business cycles, provide us with the first clues about the nature of the typical cycle. Although students may take some time to digest and remember these facts, it is important to be clear about the motivation for cataloging these facts. The plan of study of this text is to view the business cycle as a puzzle that we hope to solve. Our task is much the same as a detective trying to solve a murder mystery. The first task is to collect clues. The clues in the study of business cycles are the regularities chronicled in this chapter. Later on we will begin to encounter “suspect” causes of business cycles. In order to solve the mystery, we need to deduce the “who,” “what” and “why” of our mystery. We cannot begin the deduction process before first collecting the clues. Students need to understand this detective process. Otherwise, the clues presented in this chapter will be nothing more than a laundry list that they must memorize.Classroom Discussion TopicsTo get the ball rolling it might be useful to ask the students about whether they have concerns about recessions. Is the economy currently in a recession? When was the economy most recently in recession? The obvious candidate is the recession of 2001. One interesting point concerns the duration of the recession. Real GDP declined only in the first three quarters of 2001. However, even as of this writing in early 2007, many people perceive that the U.S. economy is still in a recession. This concern possibly reflects the fact that, through the third quarter of 2003, employment has continued to decrease and has only moderately recuperated since, as noted in the table below. Should we revise the definition of a recession by basing it on movements in employment or the unemployment rate? Which set of data provides a better picture of the overall well-being of the economy?Chapter 3 Business Cycle Measurement 21 Real GDP and Employment, 2000–2003QuarterReal GDP(millions of 2000 dollars)Employment/Population Ratio(%)2000q1 9,695.6 64.62000q2 9,847.9 64.62000q3 9,836.6 64.22000q4 9,887.7 64.32001q1 9,875.6 64.32001q2 9,905.9 63.82001q3 9,871.1 63.52001q4 9,910.0 63.02002q1 9,977.3 62.82002q2 10,031.6 62.82002q3 10,090.7 62.82002q4 10,095.8 62.52003q1 10,126.0 62.52003q2 10,212.7 62.32003q3 10,398.7 62.12003q4 10,467.0 62.22004q1 10,566.3 62.32004q2 10,671.5 62.32004q3 10,753.3 62.42004q4 10,822.9 62.52005q1 10,913.8 62.42005q2 11,001.8 62.72005q3 11,115.1 62.82005q4 11,163.8 62.82006q1 11,316.4 62.92006q2 11,388.1 63.02006q3 11,443.5 63.12006q4 11,506.5 63.3Macroeconomics is primarily concerned with business cycles and economic growth. Ask the students which of these two topics is most important. A typical comparison is between the possibility of completely eliminating recessions as opposed to increasing the rate of growth by a half of one percent or so. If they could pick only one of these advances, which would they pick? Some simple calculations reveal the apparent dominance of more growth over eliminating business cycles. Ask them if they believe that there is any other cost of a recession other than the value of lost GDP. In particular, emphasize that GDP fluctuations hide a lot about fluctuations at the household level.Another potential discussion centers on the murder mystery analogy. If the students were rounding up the usual suspects of business cycle causes, which suspects would they pick? One part of detective work involves theories and hunches about what might have happened. Another less glamorous part of detective work involves ruling out some of the suspects. How can studying the clues eliminate a suspect from consideration? Emphasize the point that much of the organization of the text revolves about the possible elimination of suspected causes of business cycles based on the evidence.22 Williamson • Macroeconomics, Third EditionOutlineCyclesI. BusinessA. Features of Business Cycles1. Peaks2. Troughs3. Turning Points4. Amplitude5. Frequency6. PersistenceB. Business Cycle Regularities1. Business Cycles Are Persistent2. Deviations from Trend Are Choppy3. Variability in Amplitude4. Variability in FrequencyII. ComovementA. Time Series ObservationsB. Correlation1. Time Series Comparisons2. Scatter Plots3. Correlation CoefficientC. Cyclical Properties1. Procyclical2. Countercyclical3. AcyclicalD. Timing1. Leading2. Lagging3. CoincidentE. The Index of Leading IndicatorsF. Variability of Time SeriesIII. Components of GDPA. Consumption1. Procyclical2. Coincident3. Less Variable Than GDPB. Investment1. Procyclical2. Residential and Inventory Investment Lead GDP3. More Variable Than GDPChapter 3 Business Cycle Measurement 23IV. Nominal VariablesA. The Phillips CurveB. Aggregate Price Level1. Procyclical Since World War II2. Sometimes Countercyclical3. Lags GDPC. Money Supply1. Procyclical2. Leads GDPV. Labor Market VariablesA. Employment1. Procyclical2. Lags GDPB. Real Wage Rates1. Procyclical2. Aggregation ProblemsC. Average Labor Productivity1. Procyclical2. Coincident3. Less Variable Than GDPTextbook Question SolutionsQuestions for Review1. Business cycles are fluctuations about trend in real GDP.2. The time series of deviations from trend in real GDP is quite choppy. There is no regularity in theamplitude of fluctuations. There is no regularity in the frequency of fluctuations.3. The choppiness of fluctuations makes them difficult to predict. Choppiness also makes it difficult totell when a turning point has occurred. The lack of regularity in amplitude and frequency makes it difficult to predict their severity and length.4. Comovement is important because the regularity of such comovements suggests that business cyclesare more alike than different. This property of business cycles suggests that it may be possible to develop a general theory for business cycle analysis. This approach would be in contrast toperforming event studies of each business cycle as if it were a consequence of a unique set ofcircumstances.5. Robert Lucas has suggested, “With respect to qualitative behavior of comovements among [economictime] series, business cycles are all alike.”6. We may discern correlation in time series by observing whether one series tends to be above (below)trend when the other series is above (below) trend. Series that both tend to be above trend and below trend at the same time are positively correlated. When one series tends to be above (below) trend when the other series is below (above) trend, they are negatively correlated.24 Williamson • Macroeconomics, Third Edition7. There is an almost endless list of possibilities. Pairs of variables that are positively correlated includethe fraction of the day in sunlight and the average air temperature, and the amount of time spent studying and a student’s grade point average. Pairs of variables that are negatively correlated include the weight of a vehicle and its gasoline mileage, and the amount of home insulation and heating and cooling expenses.Note that pairs of variables may not be perfectly correlated. For example, some students are able to get good grades without studying that much. Also note that correlation says nothing about direct causality. In the sunlight and air temperature example, the direct cause of both phenomena is the fact that the earth is tilted on its axis and revolves around the sun.8. An index of leading indicators is useful because turning points in the index generally precede turningpoints in real GDP.9. The three characteristics of comovements that are most interesting to economists are whether a seriesis procyclical or countercyclical, whether the series leads or lags real GDP, and whether the series is more or less volatile than real GDP.10. Consumption and investment are both procyclical. Consumption is less variable than real GDP, whileinvestment is considerably more variable than real GDP. Consumption is coincident with real GDP.Some components of investment (residential investment and inventory investment) lead the business cycle.11. The cyclical behavior of the price level can vary across time periods and across countries. In theUnited States, the price level has been procyclical since the end of World War II. The price also tends to lag the business cycle. The money supply is procyclical and leads the business cycle.12. No. The time period 1947–2006 is best characterized as displaying a reverse Phillips curve.13. Employment is procyclical, employment lags the business cycle, and employment is less variablethan real GDP. The real wage is procyclical.Problems1. First we draw a scatter plot of the data as in the figure below.Chapter 3 Business Cycle Measurement 25(a) Although the correlation coefficient does not appear to be very large, x and y are positivelycorrelated.(b) For this part of the problem, we need to draw the data in the form of two time series plots as inthe figure below.They lags the variable x.variable(c) The two time series appear to be characterized by persistence.2. The instructions define booms and recessions as peaks and troughs that exceed 1% of GDP. Althoughthe resolution of the diagram makes it difficult to tell exactly when the 1% threshold is reached, it would appear that we have the following booms and recessions.Time Period Type Magnitude6.2%47–50 Recession3.3%50–53 Boom2.8%53–54 Recession54–55 Boom2.1%4.1%55–58 Recession2.7%60–61 Recession61–67 Boom3.0%3.4%67–71 Recession3.8%71–73 Boom73–75 Recession3.8%3.4%75–79 Boom4.7%81–82 Recession1.7%83–89 Boom1.6%90–91 Recession2.4%97–00 Boom1.8%01 Recession(a) Booms were about as frequent in both periods.(b) Recessions were more frequent in the period 1950–1970 by a margin of 2 to 1.(c) Booms were less strong in the period 1976–2006 by a margin of 2.1% to 3.0%.(d) Recessions were less severe in the period 1976–2006 by a margin of 3.0% to 3.8%.26 Williamson • Macroeconomics, Third Edition3. Higher real GDP is associated with higher consumption spending. Some of consumption spending ison imported goods.4. The positive correlation of real GDP with the index of leading indicators is quite strong. However,there are times (e.g., 1968) when movements in the two series are coincident. In such cases, the index confirms the existence of a turning point, but it fails to predict it.5. Government expenses in the cycle.(a) Difficult to tell: government expenses are clearly more variable in the first half of the sample, butthey are less variable in the second half.(b) No clear comovement emerges here. This can be explained by changing policies or by the factthat governement expenses take a while to plan, pass the legislature, and execute.(c) Sometimes it leads, sometimes it lags. But lags may be so large that they could be falselyinterpreted as leads of the next cycle, see (b).6. Exports in the cycle.(a) Exports are much more volatile than GDP.(b) Exports appear to be procyclical, but not as strongly as other aggregates.(c) There is definitively a lag.7. Series X clearly lags series Y. The two series are almost identical and are shifted in time.8. Productivity (Y/N) and employment (N) are both procyclical and both are less variable than GDP.By definition, real GDP equals productivity times employment. In an expansion, both productivity and employment increase (both are procyclical). Therefore the variability of real GDP is likely to be greater than the individual volatilities of Y/N and N. Productivity is coincident while employment lags the business cycle. For these facts to be consistent, there must be a dominant coincident factor that affects productivity independently from movements in employment itself.9. Both consumption and investment are procyclical and coincident. The key difference is thatinvestment is much more volatile than consumption. Consumer durables provide services over a horizon greater than one year. Some consumer nondurable products, like apparel, provide services well beyond the date of purchase. Services, by definition, are fully utilized at the point of sale. The same kinds of timing considerations that affect business investment are likely to come into play with consumer durables, and to a lesser extent, consumer nondurables. Therefore, it is logical that consumer durable purchases should be more volatile than consumer nondurable purchases and that consumer nondurable purchases should be more volatile than consumption of services.。

Chapter 2MeasurementTeaching GoalsStudents must understand the importance of measuring aggregate economic activity. Macroeconomics hopes to produce theories that provide useful insights and policy conclusions. To be credible, such theories must produce hypotheses that evidence could possibly refute. Macroeconomic measurement provides such evidence. Without macroeconomic measurements, macroeconomics could not be a social science, and would rather consist of philosophizing and pontificating. Market transactions provide the most simple and direct measurements. Macroeconomists’ most basic measurement is Gross Domestic Product (GDP), the value of final, domestically market output produced during a given period of time.In the United States, the Commerce Department’s National Income and Product Accounts provide official estimates of GDP. These accounts employ their own set of accounting rules to ensure internal consistency and to provide several separate estimates of GDP. These separate estimates are provided by the product accounts, the expenditure accounts, and the income accounts. The various accounting conventions may, at first glance, be rather dry and complicated. However, students can only easily digest the material in later chapters if they have a good grounding in the fundamentals.GDP changes through time because different amounts of goods and services are produced, and such goods and services are sold at different prices. Standards of living are determined by the amounts of goods and services produced, not by the prices they command in the market. While GDP is relatively easy to measure, the decomposition of changes in real GDP into quantity and price components is much more difficult. This kind of problem is less pressing for microeconomists. It is easy to separately measure the number of apples sold and the price of each apple. Because macroeconomics deals with aggregate output, the differentiation of price and quantity is much less easily apparent. It is important to emphasize that while there may be more or less reasonable approaches to this problem, there is no unambiguous best approach. Since many important policy discussions involve debates about output and price measurements, it is very important to understand exactly how such measurements are produced.Classroom Discussion TopicsAs the author demonstrates in presenting this chapter’s material, much of this material is best learned by example. Rather than simply working through the examples from the text or making up your own, the material may resonate better if the students come up with their own examples. They can start by picking a single good, and by the choice of their numbers they provide their own implied decomposition of output into wage and profit income. Later on, encourage them to suggest intermediate input production, inventory adjustments, international transactions, a government sector, and so on. Such an exercise may help assure them that the identities presented in the text are more than simply abstract constructions.If many of your students are familiar with accounting principles, it may also be useful to present the National Income and Product Account with the “T” accounts. Highlighting how every income is an expense elsewhere. Make one account for each of the firms, one for the household and one for the government. Add another account for the rest of the world when discussing the example with international trade. This procedure can highlight how some entities can be inferred from others because accounting10 Williamson • Macroeconomics, Third Editionidentities must hold. It makes it also easier to determine consumption for some student Social Security benefits are indexed to the Consumer Price Index. Explain with an example exactly how these adjustments are made. Ask the students if they think that this procedure is “fair.” Another topic for concern is the stagnation in the growth of measured real wages. Real wages are measured by dividing (for example) average hourly wages paid in manufacturing by the consumer price index. Ask students if measured changes in real wages confirm or conflict with their general beliefs about whether the typical worker is better or worse off than 10 or 20 years ago. How does possible mis-measurement of prices reconcile any apparent differences between casual impressions and statistical evidence?The text discusses why unemployment may or may not be a good measure of labor market tightness. Another interpretation of the unemployment rate is as a(n inverse) measure of economic welfare. Ask the students if they agree with this interpretation. Does the unemployment rate help factor in considerations like equal distribution of income? How can the unemployment rate factor in considerations like higher income per employed worker? Discuss possible pros and cons of using unemployment rather than per capita real GDP as a measure of well-being. Can unemployment be too low? Why or why not?OutlineI. Measuring GDP: The National Income and Product AccountsA. What Is GDP and How Do We Measure It?1. GDP: Value of Domestically Produced Output2. Commerce Department’s National Income and Product Accounts3. Business, Consumer, and Government AccountingB. The Product Approach1. Value Added2. Intermediate Good InputsC. The Expenditure Approach1. Consumption2. Investment3. Government Spending4. Net ExportsD. The Income Approach1. Wage Income2. After-Tax Profits3. Interest Income4. Taxes5. The Income-Expenditure IdentityE. Gross National Product (GNP)1. Treatment of Foreign Income2. GNP = GDP + Net Foreign IncomeF. What Does GDP Leave Out?1. GDP and Welfarea. Income Distributionb. Non-Market Production2. Measuring Market Productiona. The Underground Economyb. Valuing Government ProductionChapter 2 Measurement 11G. Expenditure Components1. Consumptiona. Durable Goodsb. Non-Durable Goodsc. Services2. Investmenta. Fixed Investment: Nonresidential and Residentialb. Inventory Investment3. Net Exportsa. Exportsb. Imports4. Government Expendituresa. Federal Defenseb. Federal Non-Defensec. State and Locald. Treatment of Transfer PaymentsII. Nominal and Real GDP and Price IndicesA. Real GDP1. Output Valued at Base Year Prices2 Chain Weighted Real GDPB. Measures of the Price Level1. Implicit GDP Price Deflator2. Consumer Price Index (CPI)C. Problems Measuring Real GDP and Prices1. Substitution Biases2. Accounting for Quality Changes3. Treatment of Newly Introduced GoodsIII. Savings, Wealth, and CapitalA. Stocks and FlowsB. Private Disposable Income and Private Sector Saving1.d Y Y NFP TR INT T =+++− 2.p d S Y C =− C. Government Surpluses, Deficits, and Government Saving1.g S T TR INT G =−−− 2. g D S =− D. National Saving: p g S S S Y NFP C G =+=+−−E. Saving, Investment, and the Current Account1. NFP NX I S ++=2. CA I S NFP NX CA +=⇒+=F. The Stock of Capital1. Wealth ΔS ⇒2. K I Δ⇒3. Claims on Foreigners CA ⇒12 Williamson • Macroeconomics, Third EditionIV. Labor Market MeasurementA. BLS Categories1. Employed2. Unemployed3. Not in the Labor ForceB. The Unemployment RateNumber unemployed=Unemployment RateLabor forceC. The Participation RateLabor force=Participation RateTotal working age populationD. Unemployment and Labor Force Tightness1. Discouraged Workers2. Job Search IntensityTextbook Question SolutionsQuestions for Review1. Product, income, and expenditure approaches.2. For each producer, value added is equal to the value of total production minus the cost ofintermediate inputs.3. This identity emphasizes the point that all sales of output provide income somewhere in the economy.The identity also provides two separate ways of measuring total output in the economy.4. GNP is equal to GDP (domestic production) plus net factor payments from abroad. Net factorpayments represent income for domestic residents that are earned from production that takes place in foreign countries.5. GDP provides a reasonable approximation of economic welfare. However, GDP ignores the value ofnonmarket economic activity. GDP also measures only total income without reference to how that income is distributed.6. Measured GDP does not include production in the underground economy, which is difficult toestimate. GDP also measures the value of government spending at its cost of production, which may be greater or less than its true value.7. The largest component is consumption, which represents about 2/3 of GDP.8. Investment is equal to private, domestic expenditure on goods and services (Y − G − NX) minusconsumption. Investment includes residential investment, nonresidential investment, and inventory investment.9. National defense spending represents about 5% of GDP.Chapter 2 Measurement 13 10. GDP values production at market prices. Real GDP compares different years’ production at a specificset of prices. These prices are those that prevailed in the base year. Real GDP is therefore a weighted average of individual production levels. The weights are determined according to prevailing relative prices in the base year. Because relative prices change over time, comparisons of real GDP across time can differ according to the chosen base year.11. Chain weighting directly compares production levels only in adjacent years. The price weights aredetermined by averaging the prices of the individual goods and services over the two adjacent years.12. Real GDP is difficult to measure due to changes over time in relative prices, difficulties in estimatingthe extent of quality changes, and how one estimates the value of newly introduced goods.13. Private saving measures additions to private sector wealth. Government saving measures reductionsin government debt (increases in government wealth). National saving measures additions to national wealth. National saving is equal to private saving plus government saving.14. National wealth is accumulated as increases in the domestic stock of capital (domestic investment)and increases in claims against foreigners (the current account surplus).15. Measured unemployment excludes discouraged workers. Measured unemployment only accounts forthe number of individuals unemployed, without reference to how intensively they search for newjobs.Problems1. Product accounting adds up value added by all producers. The wheat producer has no intermediateinputs and produces 30 million bushels at $3/bu. for $90 million. The bread producer produces100 million loaves at $3.50/loaf for $350 million. The bread producer uses $75 million worth ofwheat as an input. Therefore, the bread producer’s value added is $275 million. Total GDP istherefore $90 million + $275 million = $365 million.Expenditure accounting adds up the value of expenditures on final output. Consumers buy100 million loaves at $3.50/loaf for $350 million. The wheat producer adds 5 million bushels ofwheat to inventory. Therefore, investment spending is equal to 5 million bushels of wheat valued at $3/bu., which costs $15 million. Total GDP is therefore $350 million + $15 million = $365 million.2. Coal producer, steel producer, and consumers.(a) (i) Product approach: Coal producer produces 15 million tons of coal at $5/ton, which adds$75 million to GDP. The steel producer produces 10 million tons of steel at $20/ton, whichis worth $200 million. The steel producer pays $125 million for 25 million tons of coal at$5/ton. The steel producer’s value added is therefore $75 million. GDP is equal to$75 million + $75 million = $150 million.(ii) Expenditure approach: Consumers buy 8 million tons of steel at $20/ton, so consumption is $160 million. There is no investment and no government spending. Exports are 2 milliontons of steel at $20/ton, which is worth $40 million. Imports are 10 million tons of coal at$5/ton, which is worth $50 million. Net exports are therefore equal to $40 million −$50 million =−$10 million. GDP is therefore equal to $160 million + (−$10 million) =$150 million.14 Williamson • Macroeconomics, Third Edition(iii) Income approach: The coal producer pays $50 million in wages and the steel producer pays $40 million in wages, so total wages in the economy equal $90 million. The coal producerreceives $75 million in revenue for selling 15 million tons at $15/ton. The coal producerpays $50 million in wages, so the coal producer’s profits are $25 million. The steel producerreceives $200 million in revenue for selling 10 million tons of steel at $20/ton. The steelproducer pays $40 million in wages and pays $125 million for the 25 million tons ofcoal that it needs to produce steel. The steel producer’s profits are therefore equal to$200 million − $40 million − $125 million = $35 million. Total profit income in theeconomy is therefore $25 million + $35 million = $60 million. GDP therefore is equal towage income ($90 million) plus profit income ($60 million). GDP is therefore $150 million.(b) There are no net factor payments from abroad in this example. Therefore, the current accountsurplus is equal to net exports, which is equal to (−$10 million).(c) As originally formulated, GNP is equal to GDP, which is equal to $150 million. Alternatively, ifforeigners receive $25 million in coal industry profits as income, then net factor payments from abroad are (−$25 million), so GNP is equal to $125 million.3. Wheat and Bread(a) Product approach: Firm A produces 50,000 bushels of wheat, with no intermediate goods inputs. At$3/bu., the value of Firm A’s production is equal to $150,000. Firm B produces 50,000 loaves ofbread at $2/loaf, which is valued at $100,000. Firm B pays $60,000 to firm A for 20,000 bushels of wheat, which is an intermediate input. Firm B’s value added is therefore $40,000. GDP is therefore equal to $190,000.(b) Expenditure approach: Consumers buy 50,000 loaves of domestically produced bread at $2/loafand 15,000 loaves of imported bread at $1/loaf. Consumption spending is therefore equal to$100,000 + $15,000 = $115,000. Firm A adds 5,000 bushels of wheat to inventory. Wheat isworth $3/bu., so investment is equal to $15,000. Firm A exports 25,000 bushels of wheat for$3/bu. Exports are $75,000. Consumers import 15,000 loaves of bread at $1/loaf. Imports are$15,000. Net exports are equal to $75,000 − $15,000 = $60,000. There is no governmentspending. GDP is equal to consumption ($115,000) plus investment ($15,000) plus net exports($60,000). GDP is therefore equal to $190,000.(c) Income approach: Firm A pays $50,000 in wages. Firm B pays $20,000 in wages. Total wagesare therefore $70,000. Firm A produces $150,000 worth of wheat and pays $50,000 in wages.Firm A’s profits are $100,000. Firm B produces $100,000 worth of bread. Firm B pays $20,000in wages and pays $60,000 to Firm A for wheat. Firm B’s profits are $100,000 − $20,000 −$60,000 = $20,000. Total profit income in the economy equals $100,000 + $20, 000 = $120,000.Total wage income ($70,000) plus profit income ($120,000) equals $190,000. GDP is therefore$190,000.Chapter 2 Measurement 15 4. Price and quantity data are given as the following.Year 1Good Quanti tyPri ceComputers 20$1,000 Bread 10,000$1.00Year 2Good Quanti tyPri ceComputers 25$1,500Bread 12,000$1.10(a) Year 1 nominal GDP =×+×=20$1,00010,000$1.00$30,000.Year 2 nominal GDP =×+×=25$1,50012,000$1.10$50,700.With year 1 as the base year, we need to value both years’ production at year 1 prices. In the base year, year 1, real GDP equals nominal GDP equals $30,000. In year 2, we need to value year 2’s output at year 1 prices. Year 2 real GDP =×+×=25$1,00012,000$1.00$37,000. The percentage change in real GDP equals ($37,000 − $30,000)/$30,000 = 23.33%.We next calculate chain-weighted real GDP. At year 1 prices, the ratio of year 2 real GDP to year1 real GDP equals g1= ($37,000/$30,000) = 1.2333. We must next compute real GDP using year2 prices. Year 2 GDP valued at year 2 prices equals year 2 nominal GDP = $50,700. Year 1 GDPvalued at year 2 prices equals (20 × $1,500 + 10,000 × $1.10) = $41,000. The ratio of year 2 GDP at year 2 prices to year 1 GDP at year 2 prices equals g2=chain-weighted ratio of real GDP in the two years therefore is equal to 1.23496cg==. The percentage change chain-weighted real GDP from year 1 to year 2 is therefore approximately23.5%.If we (arbitrarily) designate year 1 as the base year, then year 1 chain-weighted GDP equals nominal GDP equals $30,000. Year 2 chain-weighted real GDP is equal to (1.23496 × $30,000) = $37,048.75.(b) To calculate the implicit GDP deflator, we divide nominal GDP by real GDP, and then multiplyby 100 to express as an index number. With year 1 as the base year, base year nominal GDP equals base year real GDP, so the base year implicit GDP deflator is 100. For the year 2, the implicit GDP deflator is ($50,700/$37,000) × 100 = 137.0. The percentage change in the deflator is equal to 37.0%.With chain weighting, and the base year set at year 1, the year 1 GDP deflator equals($30,000/$30,000) × 100 = 100. The chain-weighted deflator for year 2 is now equal to($50,700/$37,048.75) × 100 = 136.85. The percentage change in the chain-weighted deflator equals 36.85%.16 Williamson • Macroeconomics, Third Edition(c) We next consider the possibility that year 2 computers are twice as productive as year1 computers. As one possibility, let us define a “computer” as a year 1 computer. In this case,the 25 computers produced in year 2 are the equivalent of 50 year 1 computers. Each year 1computer now sells for $750 in year 2. We now revise the original data as:Year 1Good Quanti tyPri ceYear 1 Computers 20 $1,000Bread 10,000$1.00Year 2Good Quanti tyPri ceYear 1 Computers 50 $750Bread 12,000$1.10First, note that the change in the definition of a “computer” does not affect the calculations of nominal GDP. We next compute real GDP with year 1 as the base year. Year 2 real GDP in year 1 prices is now ×+×=50$1,00012,000$1.00$62,000. The percentage change in real GDP is equal to ($62,000 − $30,000)/$30,000 = 106.7%.We next revise the calculation of chain-weighted real GDP. From above, g1 equals($62,000/$30,000) = 206.67. The value of year 1 GDP at year 2 prices equals $26,000. Therefore,g 2 equals ($50,700/$26,000) = 1.95. 200.75. The percentage change chain-weighted real GDPfrom year 1 to year 2 is therefore 100.75%.If we (arbitrarily) designate year 1 as the base year, then year 1 chain-weighted GDP equalsnominal GDP equals $30,000. Year 2 chain-weighted real GDP is equal to (2.0075 × $30,000) = $60,225. The chain-weighted deflator for year 1 is automatically 100. The chain-weighteddeflator for year 2 equals ($50,700/$60,225) × 100 = 84.18. The percentage rate of change of the chain-weighted deflator equals −15.8%.When there is no quality change, the difference between using year 1 as the base year and using chain weighting is relatively small. Factoring in the increased performance of year 2 computers, the production of computers rises dramatically while its relative price falls. Compared withearlier practices, chain weighting provides a smaller estimate of the increase in production and a smaller estimate of the reduction in prices. This difference is due to the fact that the relative price of the good that increases most in quantity (computers) is much higher in year 1. Therefore, the use of historical prices puts more weight on the increase in quality-adjusted computer output. 5. Price and quantity data are given as the following:Year 1GoodQuantity(million lbs.)Price(per lb.)Broccoli 1,500 $0.50 Cauliflower 300$0.80Year 2GoodQuantity(million lbs.)Price(per lb.)Broccoli 2,400 $0.60 Cauliflower 350$0.85Chapter 2 Measurement 17(a) Year 1 nominal GDP = Year 1 real GDP =×+×=1,500million$0.50300million$0.80 $990million.Year 2 nominal GDP=×+×=2,400million$0.60350million$0.85$1,730.5million Year 2 real GDP=×+×=2,400million$0.50350million$0.80$1,450million.Year 1 GDP deflator equals 100.Year 2 GDP deflator equals ($1,730.5/$1,450) × 100 = 119.3.The percentage change in the deflator equals 19.3%.(b) Year 1 production (market basket) at year 1 prices equals year 1 nominal GDP = $990 million.The value of the market basket at year 2 prices is equal to ×+×1,500million$0.60300million $0.85= $1,050 million.Year 1 CPI equals 100.Year 2 CPI equals ($1,050/$990) × 100 = 106.1.The percentage change in the CPI equals 6.1%.The relative price of broccoli has gone up. The relative quantity of broccoli has also gone up. The CPI attaches a smaller weight to the price of broccoli, and so the CPI shows less inflation.6. Corn producer, consumers, and government.(a) (i) Product approach: There are no intermediate goods inputs. The corn producer grows30 million bushels of corn. Each bushel of corn is worth $5. Therefore, GDP equals$150 million.(ii) Expenditure approach: Consumers buy 20 million bushels of corn, so consumption equals $100 million. The corn producer adds 5 million bushels to inventory, so investment equals$25 million. The government buys 5 million bushels of corn, so government spendingequals $25 million. GDP equals $150 million.(iii) Income approach: Wage income is $60 million, paid by the corn producer. The corn producer’s revenue equals $150 million, including the value of its addition to inventory. Additions toinventory are treated as purchasing one owns output. The corn producer’s costs includewages of $60 million and taxes of $20 million. Therefore, profit income equals $150 million −$60 million − $20 million = $70 million. Government income equals taxes paid by the cornproducer, which equals $20 million. Therefore, GDP by income equals $60 million +$70 million + $20 million = $150 million.(b) Private disposable income equals GDP ($150 million) plus net factor payments (0) plusgovernment transfers ($5 million is Social Security benefits) plus interest on the government debt ($10 million) minus total taxes ($30 million), which equals $135 million. Private saving equalsprivate disposable income ($135 million) minus consumption ($100 million), which equals$35 million. Government saving equals government tax income ($30 million) minus transferpayments ($5 million) minus interest on the government debt ($10 million) minus governmentspending ($5 million), which equals $10 million. National saving equals private saving($35 million) plus government saving ($10 million), which equals $45 million. The government budget surplus equals government savings ($10 million). Since the budget surplus is positive, the government budget is in surplus. The government deficit is therefore equal to (−$10 million).18 Williamson • Macroeconomics, Third Edition7. Price controls.Nominal GDP is calculated by measuring output at market prices. In the event of effective pricecontrols, measured prices equal the controlled prices. However, controlled prices reflect an inaccurate measure of scarcity values. Nominal GDP is therefore distorted. In addition to distortions in nominal GDP measures, price controls also inject an inaccuracy in attempts to decompose changes in nominal GDP into movements in real GDP and movements in prices. With price controls, there is typically little or no change in white market prices over time. Alternatively, black market or scarcity value prices typically increase, perhaps dramatically. Measures of prices (in terms of scarcity values) understate inflation. Whenever inflation measures are too low, changes in real GDP overstate the extent of increases in actual production.8. Underground economy.Transactions in underground economy are performed with cash exclusively, to exploit the anonymous nature of currency. Thus, once we have established the amount of currency held abroad, we know the portion of $2,474 that is held domestically. Remove from it what is used for recorded transactions, say by using some estimate of the proportion of transactions using cash and applying this to observed GDP. Finally apply a concept of velocity of money to the remaining amount of cash to obtain the size of the underground economy.9. S p– 1 = CA + D(a) By definition:p d S Y C Y NFP TR INT T C =−=+++−− Next, recall that .Y C I G NX =+++ Substitute into the equation above and subtract I to obtain:()()p S I C I G NX NFP INT T C INX NFP G INT TR T CA D −=+++++−−−=++++−=+(b) Private saving, which is not used to finance domestic investment, is either lent to the domesticgovernment to finance its deficit (D ), or is lent to foreigners (CA ).10. Computing capital with the perpetual inventory method.(a) First, use the formula recursively for each year:K 0 = 80K 1 = 0.9 × 80 + 10 = 82K 2 = 0.9 × 82 + 10 = 83.8K 3 = 0.9 × 83.8 + 10 = 85.42K 4 = 0.9 × 85.42 + 10 = 86.88K 5 = 0.9 × 86.88 + 10 = 88.19K 6 = 0.9 × 88.19 + 10 = 89.37K 7 = 0.9 × 89.37 + 10 = 90.43K 8 = 0.9 × 90.43 + 10 = 91.39K 9 = 0.9 × 91.39 + 10 = 92.25K 10 = 0.9 × 92.25 + 10 = 93.03(b) This time, capital stays constant at 100, as the yearly investment corresponds exactly to theamount of capital that is depreciated every year. In (a), we started with a lower level of capital, thus less depreciated than what was invested, as capital kept rising (until it would reach 100).Chapter 2 Measurement 19 11. Assume the following:10540308010520D INT T G C NFP CA S =======−= (a)201080110d p Y S C S D C =+=++=++= (b)103054015D G TR INT T TR D G INT T =++−=−−+=−−+= (c)208030130S GNP C G GNP S C G =−−=++=++= (d)13010120GDP GNP NFP =−=−= (e)Government Surplus 10g S D ==−=− (f)51015CA NX NFP NX CA NFP =+=−=−−=− (g)12080301525GDP C I G NXI GDP C G NX =+++=−−−=−−+=。

一、教材上的思考与练习题参考答案梗概1GDP与GNP这两个指标的运用功能有何差异答GDP衡量的是一国领土范围内或境内所有产出的总产值而不管这些产值的所有者是本国公民还是外国公民。

GNP衡量的是一国国民或公民的总收入而不管其收入是从国内还是从国外获取的。

由于来自国外的净要素收入的数据不足GNP较难统计GDP则较易衡量GDP相对于GNP来说是国内就业潜力的更好衡量指标如本国使用外资时解决的是本国就业问题。

2某国的企业大量缩减在国内的投资增加在国外的投资这对该国的GDP与GNP有何影响答会减少该国的GDP或者放缓该国GDP的增长速度并增加该国的GNP。

3阐释GDP的三种统计方法的基本理论原理。

答生产法是从生产的角度按市场价格首先计算各部门提供的产品和劳务中的增加值然后再将各部门的增加值相加即为统计期内的GDP。

一个国家在一定时期内生产的全部最终产品和劳务会被各经济主体所购买因此将各经济主体在该时期的购买额或支出额加总便可得到全部最终产品和劳务的总产值即GDP。

这便是支出法的基本原理。

一个国家在一定时期内的GDP是由劳动、资本等各种生产要素和政府这一服务性要素共同创造出来的因此它会分解为各种要素的收入。

于是将这些要素收入全部加总并进行必要的技术调整便可得到对应的GDP。

这是收入法的基本原理。

4登陆国家统计局网站阅读最近一个年份的国民经济和社会发展统计公报了解该年的GDP等数据。

答略。

5教师在课堂上提问在两部门经济中Y=C+S那人们在口袋中的零用钱和用于购买股票、债券的收入不是没有被计入吗谁来解释一下学生大头回答说这些收入在国民收入总量中占的比例很小所以可以忽略不计。

学生大眼回答说因为储蓄被定义为总收入中未用于消费的部分所以购买股票、债券的收入及零用钱被归于储蓄S中计入进去了。

你同意谁的看法答大眼说得对。

6从GDP指标的局限性出发分析树立科学的社会经济发展观的重要性。

答正是由于GDP有很大的局限性不能完全真实地反映国民的福利享受状况所以不能单纯地追求GDP的增长而要树立科学的社会经济发展观GDP的增长不是社会经济发展的唯一内容。

宏观经济学威廉森答案1 宏观经济学（Macroeconomics）宏观经济学是研究经济发展，尤其是经济政策及其影响方面的学科。

它讨论了国民经济、宏观经济政策、国际贸易、货币政策、财政政策和宏观经济分析等主题。

宏观经济学的研究者经常意在探讨如何促进持续的经济增长和繁荣以及改善国家的国民收入水平，以及资本、人力资本、技术和自然资源等如何增加生产效率。

2 威廉森（Williamson）威廉森是20世纪末知名的经济学家，他对宏观经济学做出重大贡献，推导了克莱顿-史密斯（Coulson-Smith）经济模型、威廉森N条折现，以及威廉森宏测试和宏周期理论，并且在宏观经济思想有着重要影响。

威廉森的理论强调的是经济的动态性，将动态分析应用于稳定的经济现象；他的主要理论概念是威廉森宏测试，该系统密切研究多次估量的结果，检测实际观测值是否具有投资性和现代货币性。

3 重要理论威廉森将宏观经济学——国民经济统计和经济模型——结合到一起，发展出了一种新的方法——威廉森宏测试，该方法用来量化超过数个季度展开的经济变量，根据动态视角研究经济波动；他还推导了威廉森N条折现（Williamson N-discount factor），它是一种金融工具，用来度量未来相当于现在投资的潜力；威廉森宏周期理论则是用来衡量短期内的经济起伏的技术，他认为经济波动往往可以被分解为“指数”和“震荡”，而且他对传统宏观经济学的理论框架也进行了重大更新：他将宏观经济中的“财政政策”和“货币政策”视为一个整体，使它们具备了更大的可能性。

4 对其他经济学家的开拓威廉森的思想和理论为经济研究开创了先河，大大推动了宏观经济学的发展。

他继承并发展了许多古典经济学家的理论基础，强调动态分析，充分发挥了宏观经济学的生物效应和科学方法；同时他也与其他经济学家一起发展，如范一夫、汤普森、埃希尔、梅西斯等等，他们推动了宏观经济学多学科交叉研究，共同推动经济学前进。

5 总结威廉森是世界著名经济学家，他的宏观经济学理论和方法对宏观经济学的发展起到了重要的推动作用。

第3章经济周期的衡量3.1 复习笔记一、GDP波动的规律性经济周期（business cycles）的主要明显特征是：围绕着实际GDP的趋势波动。

1．理想化的经济周期图3-1显示了实际GDP中理想化的经济周期，它围绕着长期趋势波动。

实际GDP有波峰（peaks）和波谷（troughs），波峰是对趋势相对大的正偏离，波谷是对趋势相对大的负偏离。

偏离实际GDP趋势中的波峰和波谷被称为拐点（turning points）。

对趋势的最大偏离称作经济周期的波幅（amplitude）。

实际GDP中波峰每年发生的次数称作经济周期的频率（frequency）。

图3-1 理想化的经济周期2．偏离GDP趋势的特征（1）对实际GDP趋势的偏离具有持续性。

（2）偏离实际GDP趋势的时间序列很不稳定。

（3）实际GDP围绕趋势波动的幅度没有规律性，一些波峰和波谷意味着对趋势的巨大偏离，而另一些波峰和波谷则意味着对趋势的小幅偏离。

（4）实际GDP围绕趋势波动的频率没有规律性。

实际GDP中波峰和波谷之间的时间跨度变化很大。

二、联动1．联动（comovement）尽管实际GDP波动具有不规律的形式，但宏观经济诸变量一起波动的格局显示出了较强的规律性，这些波动格局称为联动。

2．单个宏观经济变量与实际GDP的联动（1）顺周期的（procyclical）：一个经济变量对趋势的偏离和对实际GDP趋势的偏离正相关；（2）逆周期的（countercyclical）：一个经济变量对趋势的偏离和对实际GDP趋势的偏离负相关；（3）非周期的（acyclical）：既不顺周期，也不逆周期。

3．相关系数（correlation coefficient）它是衡量两个变量相关程度的指标。

其取值范围是-1～1。

如果相关系数为1，那么两个变量完全正相关（perfectly positively correlated）；如果相关系数为-1，那么两个变量完全负相关（perfectly negatively correlated）；如果相关系数为0，那么两个变量不相关。

宏观经济学-课后思考题答案_史蒂芬威廉森016Chapter 16Unemployment: Search and Efficiency WagesTeaching GoalsThus far in the text, the only formal explanation for the phenomenon of unemployment has been in the context of the Keynesian sticky price model. If there is nominal wage rigidity, the real wage may become stuck at a level that implies an excess supply of labor. This chapter supplies two models of unemployment that are more firmly grounded in microeconomic principles.The first model of unemployment is the search model. In this framework, unemployment is a socially useful phenomenon that may improve the quality of matches between workers and firms. When studying the model, it is important to remind students that factors that raise the equilibrium unemployment rate may not be bad, and factors that reduce the equilibrium unemployment may not be good. The focus of the search model is primarily microeconomic in nature. The search model explains what incentives work as households change their behavior in the face of new policies. The microfoundations are very powerful here, as they allow us to experiment at no cost with various policy schemes, yet they give us results of macroeconomic importance: how do taxes or unemployment insurance alter the unemployment rate?The second model of unemployment is the efficiency wage model. This model provides an explanation of unemployment that is hard to empirically distinguish from the Keynesian sticky wage model. In both models, unemployed workers stand willingto accept employment at the prevailing wage rate, and yet cannot find work. However, in the sticky wage model it is plausible to imagine a scenario in which an unemployed worker can successfully agree to work at a wage lower than the prevailing wage. In the efficiency wage model, it is never in the interest of a firm to hire such a “bargain” worker, because the worker cannot commit to put in enough effort to make his employment worthwhile to the firm. The main advantage of this model is that it reconciles such “involuntary” unemployment with optimizing behavior. However, the model is less successful as a part of a consistent explanation of business cycles. The model cannot easily explain the fact that the real wage rate is procyclical.Classroom Discussion TopicsBy now, students should be comfortable with the idea that perfectly competitive markets generate efficient outcomes, as long as there are no externalities. In what sense does the structure of the job search model approximate perfect competition? Are there any possible sources of externalities? Is there some sense in which there may be elements of monopolistic competition? If the job search model is anything like a competitive market, do we have any reason to think that the unemployment rate might be too high or too low relative to a Pareto optimum? If an undistorted market provides the right amount of unemployment, then unemployment insurance leads to an inefficiently high rate of unemployment. Does this line of reasoning make a good case for eliminating unemployment insurance? Where does the desire to avoid risks come in? And moral hazard?152 Williamson ? Macroeconomics, Third EditionIt is useful to point out that the fundamental theorems of welfare economics are worked out in a model in which there is complete information, and where no passage of time is needed to equilibrate the market. Job search is only necessary because workers do not possess complete information, and time is required to acquire additional information. Do these considerations have any relevance for the question of the socially optimum amount of unemployment?The efficiency wage model does not do a very good job of explaining business cycles because it cannot rationalize a procyclical real wage rate. Suppose instead that we had an economy with two sectors. In one sector, firms find it optimal to pay an efficiency wage and there is an excess supply of workers at the optimal efficiency wage. In the other sector, perhaps worker effort and ability are directly observable. Now suppose that there is an increase in total factor productivity. While the wage paid in the efficiency wage sector may be unchanged, what is the likely effect on wages in the rest of the economy? Does this consideration improve the ability of the efficiency wage model to explain business cycle models? Is there likely to be any unemployment in this kind of economy? Why or why not? If there is no unemployment, does the existence of an efficiency wage sector add anything to our understanding of business cycles over and above the explanation given by the real business cycle model?OutlineI. Behavior of Unemployment and Participation RatesA. Determinants of the Unemployment Rate1. Aggregate Economic Activity2. Demography3. Government-Provided Unemployment Insurance4. Sectoral ShiftsB. The Participation Rate1. L ong-Run Trendsa. Participation Rate of Menb. Participation Rate of Women2. Cyclical VariationsII. A Search Model of UnemploymentA. Welfare of Employed Workers1. Real Wage2. Separation Rate3. Wage Income TaxB. Welfare of Unemployed Workers1. Size of Unemployment Insurance Benefit2. Frequency of Job Offers3. Unemployment Insurance Benefit T axC. Reservation Wage1. Welfare of Job Offer ≥ Welfare of Remaining Unemployed2. Increase in Unemployment Insurance Benefit *w ?↑3. Increase in Wage Tax *w ?↑Chapter 16 Unemployment: Search and Efficiency Wages 153D. Determinants of the Equilibrium Unemployment Rate1. Flows out of Employment2. Flows out of Unemployment3. The Wage Offer Distribution4. Effects of Disturbancesa. Increase in Unemployment Insurance Benefits U ?↑b. Increase in Job Offer Rate U ?↓c. Increase in Wage Tax U ?↑d. Increase in Benefit Tax U ?↓5. The Natural Rate of UnemploymentIII. The Efficiency Wage ModelA. Wages and Effort1. Adverse Selection: Unobserved Ability2. Moral Hazard: Unobserved ShirkingB. Optimization by the Firm 1. L abor Demand: ()()e w N e w MP w =2. Efficiency Wage: Maximize()e w wC. Labor Market Equilibrium1. >* Market-Clearing Wage w a. ()d s N N r <b Efficiency Wage Unemployment2. ≤* Market-Clearing Wage wD. Efficiency Wages and Business Cycles1. An Increase in Government Purchases: ,,,0r C I Y w U ↑↓↓Δ=Δ=Δ=2. An Increase in Total Factor Productivity: ,,,,0Y U C I w ↑↓↑↑Δ=3. An Improvement in Monitoring: w ↓Textbook Question SolutionsQuestions for Review1. The four key determinants of the unemployment rate are the level of aggregate economic activity,demographic factors, government intervention, and sectoral shifts.2. The unemployment rate is countercyclical.3. Different demographic groups often experience differing levels of unemployment. The unemploymentrate is higher when the composition of the work force includes a higher percentage of groups that typically experience more unemployment. As one example, younger workers whohave recentlyentered the work force typically experience more unemployment. The aggregate unemployment rate is therefore higher when young workers represent a larger-than-normal proportion of the work force.154 Williamson ? Macroeconomics, Third Edition4. The participation rate is procyclical.5. The welfare of the employed increases when the real wage increases, when the separation ratedecreases, and when taxes on wage income decrease.6. The welfare of the unemployed increases when the unemployment benefit increases, when thefrequency with which the unemployed receive job offers increases, and when the taxes onunemployment benefits decreases.7. The reservation wage is the wage offer that equates the welfare of accepting a job offer with thewelfare of remaining unemployed. The reservation wage increases when the welfare of beingemployed decreases and when the welfare of being unemployed increases.8. An increase in the unemployment benefit increases the welfare of being unemployed and thereforeincreases the reservation wage.9. An increase in the tax on wage income decreases the welfare of being employed and thereforeincreases the reservation wage.10. An increase in the unemployment insurance benefit raises the reservation rate. Therefore, theunemployed require more time to find an acceptable wageoffer, and the equilibrium unemployment rate increases.11. An increase in the job offer rate, holding the reservation wage constant, reduces the amount of time ittakes to find an acceptable job offer. This effect tends to lower the equilibrium unemployment rate.An increase in the job offer rate also increases the reservation wage. This effect tends to increase the equilibrium unemployment rate. The net effect on the unemployment rate is therefore uncertain.An active government role in helping the unemployed to find job offers is likely to increase the job offer rate.12. What matters to the unemployed is the value of the unemployment insurance benefit, net of taxes. Anincrease in taxes on unemployment insurance benefits acts in the same way as a decrease in the gross benefits.13. A higher real wage rate increases the likelihood that more able workers will accept job offers. Ifemployers cannot precisely measure the level of ability, a higher real wage rate increases the average ability level of employees working for the firm. This effect is due to adverse selection.A higher real wage rate increases the potential costs of an employee losing his or her job.If it is costly for firms to monitor the level of effort expended by its workers, a higher real wage reduces the incentives for workers to shirk. This effect is due to moral hazard.14. When the efficiency wage exceeds the market-clearing wage, there will be involuntaryunemployment in the efficiency wage model.15. An increase in government spending increases the realinterest rate, but has no effect on the levels ofoutput and employment.Chapter 16 Unemployment: Search and Efficiency Wages 155 16. An increase in total factor productivity decreases the real interest rate, and increases output andemployment. The increase in total factor productivity does not affect the real wage, unless the change in technology also affects the costs of monitoring workers’ performance.17. The efficiency wage model can account for procyclical employment, consumption, and investment.The efficiency wage model can account for countercyclical unemployment. The efficiency wage model cannot account for the procyclical behavior of the real wage rate.Problems1. An increase in the separation rate lowers the welfare from being employed, and therefore increasesthe efficiency wage. The higher reservation wage shifts the * UpH w curve to the right. The direct()effect of the increase in s shifts the (1)curve to the right. Unemployment therefore increases.s U2. An increase in the average wage paid, holding the reservation wage constant, increases the probabilityof finding an acceptable job offer. However, as long as job searchers are aware of the increase in wage rates, the reservation wage will also increase, because higher wages increase the welfare from being employed. On net, it is likely that at first approximation *H w will be unaffected, and so()there will be no change in the unemployment rate.3. The introduction of unemployment insurance benefits increases the welfare from being unemployedand increases the reservation wage. This effect increases the equilibrium rate of unemployment. If the insurance is paid for from a tax on wage income, then after-tax wages decrease. However, the reduction in the wage rate will likely result in an equal reduction in the reservation wage, so that *H w will be unaffected. Therefore, unemployment increases.()4. There are two channels through which more stringent qualification for unemployment insurancemay operate. For those currently employed, possible difficulties in qualifying would decrease the separation rate. Workers would be more reluctant to quit if they may not qualify for benefits and workers might perform better on the job reducing the incidence of firing. The unemployed who are covered by insurance would be unaffected. However, the pool of the unemployed would now include more potential workers not receiving benefits and these individuals are likely to have lower reservation wages. The average reservation wage would decrease and the long-run unemployment rate would decrease.5. Increased difficulty in distinguishing ability levels is much like an increased difficulty in monitoringworker effort. The effort function therefore shifts down and to the right. The efficiency wagetherefore increases.However, a careful modeling of the adverse selection problem is more complicated than the modeling of the moralhazard problem. If a firm believes that it has some ability to distinguish between high- and low-ability workers, then it is likely to offer different wages to those believed to be of high rather than low ability. In a more complicated model of such a segmented market, it is likely that an increase in the difficulty of distinguishing between workers will lead to an increase in the wages of low-ability workers and a decrease in wages of high-ability workers.156 Williamson ? Macroeconomics, Third Edition6. The destruction of capital is much like a decrease in total factor productivity. The labor demand curveshifts to the left. As long as there is no change in the ability to monitor, there will be no change in the efficiency wage. Output and employment decrease, unemployment increases, and the real interest rate increases.7. The efficiency wage model is a model that predicts real wage rigidity, not nominal wage rigidity. Anincrease in the money supply leads to an equiproportional increase in nominal wages and prices.Money is therefore neutral.8. According to the permanent income hypothesis, a permanent increase in government spending is likely to lead to an equal-sized decrease in consumption spending. The output demand curve therefore does not shift. The wealth effect of the increase in government spending increases labor supply. However, in the efficiency wage model output and employment are determined by labor demand. Therefore, the output supply curve also does not shift. Output, employment, the real wage, investment, and the real interest rate are all unchanged. The only effects of the permanent increase ingovernment spending are a decrease in consumption and an increase in unemployment. There is no crowding out of investment spending. Instead, there is a one-for-one crowding out of consumption spending.。

Macroeconomics, 3e (Williamson)Chapter 13 I nternational Trade in Goods and Assets1) A small open economy is an economyA) i n which both imports and exports are less than 5% of GDP.B) w hose firms and consumers are individually, but not collectively price takers.C) w hose firms and consumers are collectively, but not individually price takers.D) w hose firms and consumers are individually and collectively price takers.Answer: DQuestion Status: P revious Edition2) I n an open, two-good economy in a two-good world, the relative price of one good in termsof the other is called theA) r elative advantage.B) a bsolute advantage.C) t erms of trade.D) i nternational purchasing price index.Answer: CQuestion Status: P revious Edition3) W hich of the following pairs of terms can be used interchangeably?A) t he terms of trade and comparative advantageB) c omparative advantage and purchasing power parityC) p urchasing power parity and the real exchange rateD) t he real exchange rate and the terms of tradeAnswer: DQuestion Status: P revious Edition4) I n a two-good economy, the production possibilities frontier isA) c oncave because the marginal rate of transformation increases as we move down thePPF.B) c oncave because the marginal rate of transformation decreases as we move down thePPF.C) c onvex because the marginal rate of transformation increases as we move down thePPF.D) c onvex because the marginal rate of transformation decreases as we move down thePPF.Answer: AQuestion Status: P revious Edition5) C omparative advantage is determined by theA) s lope of the representative consumer's indifference curve.B) s lope of the country's production possibilities frontier.C) c urvature of the representative consumer's indifference curve.D) c urvature of the country's production possibilities frontier.Answer: BQuestion Status: P revious Edition6) I n a competitive, one-period, two-good economy without tradeA) t he marginal rate of substitution equals the marginal rate of transformation.B) t he marginal rate of substitution equals the real interest rate.C) t he marginal rate of transformation equals the real interest rate.D) a ll of the above are true.Answer: AQuestion Status: N ew7) O nce an economy opens to tradeA) t he production mix stays the same.B) t he firm obtains monopoly power.C) t he firm produces more of all goods.D) t he household consumes a preferred bundle of goods.Answer: DQuestion Status: N ew8) O nce an economy opens to tradeA) b oth economies lose.B) t he economy with the higher terms of trade loses.C) t he economy with the lower terms of trade loses.D) n o economy loses.Answer: DQuestion Status: N ew9) C omparative advantage means thatA) t he economy produces more with trade because it is better at everything.B) t he terms of trade are invariant to conditions inside the small open economy.C) t he economy specializes in what it is good at producing.D) t here is no free lunch.Answer: CQuestion Status: N ew10) T he terms of trade move in favor of a country when theA) a bsolute price of imports decreases.B) a bsolute price of exports increases.C) r elative price of imports increases.D) r elative price of imports decreases.Answer: DQuestion Status: P revious Edition11) T he real exchange moves in favor of a country when theA) a bsolute price of imports decreases.B) a bsolute price of exports increases.C) r elative price of exports increases.D) r elative price of exports decreases.Answer: CQuestion Status: N ew12) I n a two-good, one-period model, when the terms of trade move in your favorA) e xports unambiguously increase and imports unambiguously decrease.B) e xports unambiguously increase and the effect on imports is uncertain.C) t he effect on exports is uncertain and imports unambiguously decrease.D) t he effects on both exports and imports are uncertain.Answer: BQuestion Status: P revious Edition13) T o improve its terms of trade, a small open economy shouldA) p roduce more of every good.B) p roduce more of the exported good.C) p roduce more of the imported good.D) T here is nothing it can do about the terms of trade.Answer: DQuestion Status: N ew14) I n a two-good, one-period model, when the terms of trade move against youA) e xports unambiguously decrease and imports unambiguously increase.B) e xports unambiguously decrease and the effect on imports is uncertain.C) t he effect on exports is uncertain and imports unambiguously increase.D) t he effects on both exports and imports are uncertain.Answer: BQuestion Status: P revious Edition15) I n a two-good, one-period model, when the terms of trade move in your favor, theA) c urrent account surplus unambiguously increases.B) c urrent account balance unambiguously decreases.C) e ffect on the trade balance is uncertain.D) t rade balance is unchanged.Answer: DQuestion Status: P revious Edition16) I n a two-good, one-period model, when the terms of trade move in your favor, the welfareof the representative consumerA) u nambiguously increases.B) u nambiguously decreases.C) m ay either increase or decrease.D) i s unchanged.Answer: AQuestion Status: P revious Edition17) A ccording to a study by Enrique Mendoza, for all of the economies in the world, on average,terms of trade shocks account forA) a n imperceptible amount of the variation in real GDP.B) a bout 10% of the variation in real GDP.C) a bout 50% of the variation in real GDP.D) a lmost all of the variation in real GDP.Answer: CQuestion Status: P revious Edition18) T he current account surplus is notA) t he trade balance.B) t he excess of national savings over investment.C) p rivate saving less government deficit.D) o utput less taxes and trade deficit.Answer: DQuestion Status: N ew19) I n a two-good, two-period model, holding everything else constant, an increase in current-period incomeA) u nambiguously increases the current account surplus.B) u nambiguously decreases the current account surplus.C) h as an uncertain effect on the current account surplus.D) h as no effect on the current account surplus.Answer: AQuestion Status: P revious Edition20) I n a two-good, two-period model, holding everything else constant, an increase ingovernment spendingA) u nambiguously increases the current account surplus.B) u nambiguously decreases the current account surplus.C) h as an uncertain effect on the current account surplus.D) h as no effect on the current account surplus.Answer: BQuestion Status: P revious Edition21) I n a two-good, two-period model, holding everything else constant, an increase in currenttaxesA) u nambiguously increases the current account surplus.B) u nambiguously decreases the current account surplus.C) h as an uncertain effect on the current account surplus.D) h as no effect on the current account surplus, as long as Ricardian equivalence holds.Answer: DQuestion Status: P revious Edition22) I n a two-good, two-period model, holding everything else constant, an increase in futuretaxesA) u nambiguously increases the current account surplus.B) u nambiguously decreases the current account surplus.C) h as an uncertain effect on the current account surplus.D) h as no effect on the current account surplus, as long as Ricardian equivalence holds.Answer: DQuestion Status: N ew23) I n a two-good, two-period model, as long as wealth effects are small, an increase in theworld real interest rateA) i ncreases consumption and increases the current account surplus.B) i ncreases consumption and decreases the current account surplus.C) d ecreases consumption and increases the current account surplus.D) d ecreases consumption and decreases the current account surplus.Answer: CQuestion Status: P revious Edition24) T heory predicts that current account surpluses should be ________; U.S. experience since1970 suggests that current account surpluses have been ________.A) p rocyclical; procyclical.B) p rocyclical; countercyclical.C) c ountercyclical; procyclical.D) c ountercyclical; countercyclical.Answer: BQuestion Status: P revious Edition25) L ack of evidence of a pattern of international consumption smoothing is best explained byA) g overnment policies to fight trade deficits.B) t he failure of consumers in less advanced economies to act rationally.C) a tendency for business cycles to be a worldwide phenomenon.D) R icardian equivalence.Answer: CQuestion Status: P revious Edition26) T he behavior of the current account deficit and the government budget deficit in the UnitedStates in the 1980s is often referred to as theA) i nterrelated deficits.B) R eagan deficits.C) t win deficits.D) r everse deficits.Answer: CQuestion Status: P revious Edition27) T win deficits areA) t he current account deficit and the trade deficit.B) t he current account deficit and the government budget deficit.C) t he current account deficit and the private saving deficit.D) t he current account deficit and the future account deficit.Answer: BQuestion Status: N ew28) I n the 1980s in the United States, the current account surplus and the government budgetsurplus moved inA) t he same direction, which is almost always the case.B) t he same direction, which has not been typical.C) o pposite directions, which is almost always the case.D) o pposite directions, which has not been typical.Answer: BQuestion Status: P revious Edition29) C urrently in the United States, there isA) a current account surplus and a government budget surplus.B) a current account surplus and a government budget deficit.C) a current account deficit and a government budget surplus.D) a current account deficit and a government budget deficit.Answer: DQuestion Status: N ew30) R icardian equivalence suggests that government budget deficits generated by decreases incurrent taxesA) i ncrease the current account surplus.B) d ecrease the current account surplus.C) h ave no effect on the current account surplus.D) h ave unpredictable effects on the current account surplus.Answer: CQuestion Status: P revious Edition31) I ncluding investment and production in the two-good, two-period model with tradeA) a llows the country to equalize absorption and output demand.B) r enders terms of trade endogenous.C) a llows the country to react to changes in the interest rate.D) a llows the government to run budget deficits.Answer: CQuestion Status: N ew32) I n a two-good, two-period model with trade, an increase in the world real interest rateA) i ncreases domestic output and increases the current account surplus.B) i ncreases domestic output and decreases the current account surplus.C) d ecreases domestic output and increases the current account surplus.D) d ecreases domestic output and decreases the current account surplus.Answer: AQuestion Status: P revious Edition33) I n a two-good, two-period model with trade, a temporary increase in domestic governmentspendingA) i ncreases domestic output and increases the current account surplus.B) i ncreases domestic output and decreases the current account surplus.C) d ecreases domestic output and increases the current account surplus.D) d ecreases domestic output and decreases the current account surplus.Answer: BQuestion Status: P revious Edition34) I n a two-good, two-period model with trade, a permanent increase in domestic governmentspendingA) i ncreases domestic output and increases the current account surplus.B) i ncreases domestic output and decreases the current account surplus.C) d ecreases domestic output and increases the current account surplus.D) d ecreases domestic output and decreases the current account surplus.Answer: AQuestion Status: N ew35) I n a two-good, two-period model with trade, an increase in current domestic total factorproductivityA) i ncreases domestic output and increases the current account surplus.B) i ncreases domestic output and decreases the current account surplus.C) d ecreases domestic output and increases the current account surplus.D) d ecreases domestic output and decreases the current account surplus.Answer: AQuestion Status: P revious Edition36) I n a two-good, two-period model with trade, an anticipated future increase in domestictotal factor productivityA) i ncreases domestic output and increases the current account surplus.B) i ncreases domestic output and decreases the current account surplus.C) h as no effect on domestic output and increases the current account surplus.D) h as no effect on domestic output and decreases the current account surplus.Answer: DQuestion Status: P revious Edition37) I n the nineteenth century, the United States had a period of significant current accountdeficits, which contributed to economic growth. These deficits most notablyA) f inanced the Civil War.B) a llowed for a substantial increase in government spending's share of GDP.C) f inanced construction of railroads.D) f inanced the development of land-grant universities.Answer: CQuestion Status: P revious Edition38) W hen current account deficits are used to finance investment spending, such deficits may beself-correcting becauseA) t hey promote more responsible government policies.B) t he resulting increase in the capital stock over time shifts the output supply curve tothe right.C) t he resulting increase in the capital stock over time shifts the output demand curve tothe right.D) t he resulting increase in national indebtedness increases labor demand.Answer: BQuestion Status: P revious Edition。

1 / 21第3章 经济周期的衡量3.1 复习笔记一、GDP 波动的规律性经济周期（business cycles ）的主要明显特征是：围绕着实际GDP 的趋势波动。

1．理想化的经济周期图3-1显示了实际GDP 的理想化的经济周期活动，它围绕着长期趋势波动。

实际GDP 有高峰（peaks ）和低谷（troughs ），高峰是对趋势的最大正偏离，低谷是对趋势的最大负偏离。

实际GDP 偏离趋势的高峰和低谷被称为拐点（turning points ）。

对趋势的最大偏离程度称作经济周期的波幅（amplitude ）。

实际GDP 中高峰每年发生的次数称作经济周期的频率（frequency ）。

2 / 21图3-1 理想化的经济周期2．实际GDP 偏离趋势的特征（1）实际GDP 的趋势偏离具有持续性。

（2）实际GDP 偏离趋势的时间序列很不稳定。

（3）实际GDP 围绕趋势波动的幅度没有规律性，有些高峰和低谷意味着对趋势的巨大偏离，而另一些高峰和低谷则意味着对趋势的小幅偏离。

（4）实际GDP 围绕趋势波动的频率没有规律性。

实际GDP 中高峰和低谷之间的时间跨度变化很大。

3 / 21二、联动1．联动（comovement ）尽管实际GDP 波动具有不规律性，但宏观经济诸变量一起波动的格局显示出了较强的规律性，这些波动格局称为联动。

2．单个宏观经济变量与实际GDP 的联动（1）顺周期的（procyclical ）：一个经济变量的趋势偏离和实际GDP 的趋势偏离正相关。

（2）逆周期的（countercyclical ）：一个经济变量的趋势偏离和实际GDP 的趋势偏离负相关。

（3）非周期的（acyclical ）：既不顺周期，也不逆周期。

3．相关系数（correlation coefficient ）它是衡量两个变量相关程度的指标。

其取值范围是[－1，1]。

如果相关系数为1，那么两个变量完全正相关；如果相关系数为－1，那么两个变量完全负相关；如果相关系数为0，那么两个变量不相关。