斯蒂芬D威廉森宏观经济学第三版第六章Stephen D. Williamson's Macroeconomics, Third Edition chapter6
当代西方经济学主要流派(第三版)课件-第6、7章
NK的货币政策主张
NK认为，货币政策能稳定总产出和就业，货 币变动会对真实的经济增长产生影响；经济当事 人对未来的货币政策的预期行为至关重要，因而 要重视货币政策的可靠性。
一些NK主张实行通货膨胀目标制的货币政策 （inflation-targeting policy），认为盯住通货膨胀 目标的货币政策是最优的货币政策。他们主张通 过调整名义短期利率进而改变实际利率以适应经 济的变化, 从而抵消通货膨胀预期的变化。
四、新凯恩斯主义的特色
曼昆（N. Gregory Mankiw）和罗默(David Romer)在他们编 选的两卷本《新凯恩斯主义经济学》（1991年）中回答了“什么 是新凯恩斯主义经济学”。他们认为，对以下两个有关经济波动 的理论问题的回答可以帮助我们界定“什么是新凯恩斯主义”：
1、这种理论违反古典二分法吗？它断定名义变量 （如货币供给）波动影响实际变量（如产量和就业） 波动吗？
当代西方经济学主要流派
第六章 新凯恩斯主义
第一节 新凯恩斯主义概览
一、新凯恩斯主义产生的背景 二、新凯恩斯主义代表人物 三．新凯恩斯主义发展的三阶段 四、新凯恩斯主义的特色 五、新凯恩斯主义的基本假设 六、NK & NCM争论的主要问题
一、新凯恩斯主义产生的背景
20世纪80年代，西方主流经济学中出 现了一个新的流派，这就是以美国哈佛 大学教授格雷高里·曼昆(N.Gregory Mankiw)和时任斯坦福大学教授约瑟 夫·斯蒂格利茨(Joseph Stiglitz)等人为 代表的新凯恩斯主义(New Keynesianism， NK)，也叫新凯恩斯主义经济学（New Keynesian Economics，NKE）。
从NK这一方来看，它之所以要和RBC 融合，主要是因为，其一，NK在其发展过 程中遇到了和凯恩斯主义经济学一样的重 要问题，即除了动态的工资—价格设定模 型外，都与动态学不相容。以不完全竞争 为基础的NK一般均衡模型仍然是静态模型 ，像Blanchard-Kiyotaki模型（1987） 。
宏观经济学-课后思考题答案_史蒂芬威廉森016重点
Chapter 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 willing to 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 intere st of a firm to hire such a “bargain” worker, because the worker cannot commit to put in enough effort to make his employmentworthwhile to the firm. The main advantage of this model is that it reconciles such “involuntary” unemployment with optimizing beh avior. 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 efficiencywage 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 TaxC. 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 who have 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 wage offer, 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 real interest 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 incidenceof 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 moral hazard 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 Edition 6. The destruction of capital is much like a decrease in total factor productivity. The labor demand curve shifts 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. The efficiency wage model is a model that predicts real wage rigidity, not nominal wage rigidity. An increase in the money supply leads to an equiproportional increase in nominal wages and prices. Money is therefore neutral. 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 governmentspending 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 in government 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. 7. 8.。
威廉森《宏观经济学》(第3版)配套题库【模拟试题】威廉森《宏观经济学》(第3版)模拟试题及详解(一)
威廉森《宏观经济学》（第3版）模拟试题及详解（一）一、名词解释（每小题5分，共计20分）1．IS LM-模型答：IS LM-模型是由英国经济学家希克斯和美国经济学家汉森在凯恩斯宏观经济理论基础上概括出的一个经济分析模式，即“希克斯—汉森模型”，也称“希克斯—汉森综合”或“希克斯—汉森图形”。
IS LM-模型是宏观经济分析的一个重要工具，是描述产品市场和货币市场之间相互联系的理论结构。
在产品市场上，国民收入取决于消费、投资、政府支出和净出口加起来的总支出或者说总需求水平，而总需求尤其是投资需求要受到利率影响，利率则由货币市场供求情况决定，就是说，货币市场要影响产品市场；另一方面，产品市场上所决定的国民收入又会影响货币需求，从而影响利率，这又是产品市场对货币市场的影响。
可见，产品市场和货币市场是相互联系、相互作用的，而收入和利率也只有在这种相互联系、相互作用中才能决定。
IS曲线是描述产品市场达到均衡，即I S=时，国民收入与利率之间存在着反向变动关=时，国民收入和利率之间存在着同系的曲线。
LM曲线是描述货币市场达到均衡，即L M向变动关系的曲线。
把IS曲线和LM曲线放在同一个图上，就可以得出说明两个市场同时均衡时，国民收入与利率决定的IS LM-模型。
2．国内生产总值（gross domestic product，GDP）答：国内生产总值指一个国家（地区）领土范围内，本国（地区）居民和外国居民在一定时期内所生产和提供的最终物品和劳务的市场价值。
GDP一般通过支出法和收入法两种方法进行核算。
用支出法计算的国内生产总值等于消费、投资、政府支出和净出口之和；用收入法计算的国内生产总值等于工资、利息、租金、利润、间接税和企业转移支付和折旧之和。
GDP是一国范围内生产的最终产品的市场价值，因此是一个地域概念，而与此相联系的国民生产总值（GNP）则是一个国民概念，乃指某国国民所拥有的全部生产要素所生产的最终产品的市场价值。
斯蒂芬D威廉森宏观经济学第三版第十一章Stephen D. Williamson's Macroeconomics, Third Edition chapter11
11-4
Figure 11.2 Effects of a Persistent Increase in Total Factor Productivity in the Real Business Cycle Model
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
11-9
Segmented Markets Model
• Business cycles can be caused in this model by unanticipated shocks to the money supply. • Model exhibits a liquidity effect – the interest rate falls in the short run when the money supply increases. • Monetary policy can only improve the functioning of the economy if the central bank has an informational advantage over the private sector. • Fit to the data is not as good as with the real business cycle model.
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
11-10
Figure 11.5 Effects of an Unanticipated Increase in the Money Supply in the Segmented Markets Model
宏观经济学-课后思考题答案_史蒂芬威廉森006
Chapter 6Economic Growth: Malthus and SolowTeaching GoalsStudents easily take for granted the much more abundant standard of living of today as opposed to 20, 50, or 100 years ago. Sometimes it is easier to remind students of what their ancestors had to do without, rather than simply referring to per capita income levels over time. Recessions come and go, and yet economic growth swamps the lost output we endure during hard times.The typical student begins study of economic growth against the backdrop of the recent growth experience of the United States. The current standard of living in the United States vastly surpasses the current standard of living in most countries and would have been unimaginable anywhere in the world before the advent of the industrial revolution. Until about 1800, the world economy produced little more than a subsistence level of income for any but the richest individuals. Growth in per capita income was nonexistent. The Malthusian model of growth explains the tendency of increases in population to dilute any gains in productivity.The industrial revolution introduced the possibility of sustained growth in per capita income through the accumulation of physical capital. However, growth experience has varied widely around the world. The richer countries have a sustained record of growth. Per capita income in the United States has proceeded at an average rate of about 2% per year. While 2% growth may seem small, it is important for students to realize that such growth transforms into a more than doubling of per capita GDP per generation. Unfortunately, the poorer countries have remained poor. Furthermore, their growth rates have not generally matched growth rates in the richer countries, so that the poor countries fall farther and farther behind. Such differences in standards of living and growth prospects present puzzles that the study of economic growth hopes to solve.Classroom Discussion TopicsGetting students to relate to differences in standards of living can sometimes be difficult. It is easy to take one’s own standard of living for granted. An interesting discussion topic is whether students would be willing to travel back in time to 100 or 200 years ago, if they could be one of the richest people of those earlier times. Would the tradeoff be worthwhile? While students typically stress factors like antiquated view about freedom of choice, and racial and gender issues, try to encourage students to divide their concerns into those that are more economic as opposed to social. Also point out that higher standards of living allow societies to be more concerned about issues of equality when mere survival is no longer precarious.Chapter 6 Economic Growth: Malthus and Solow 53Students often view population growth as the result of cultural factors and personal preferences. Against the abundance of daily living, it is easy to forget economic factors. Ask the students for examples ofeconomic factors that might impact on fertility decisions. The Malthusian model suggests that growth may only be achieved through population control. In the modern economy, the costs of raising children can be formidable, and so there is tendency for such costs to be a disincentive to fertility. Such costs may attribute to the tendency for low fertility rates in advanced economies. In more primitive societies, having a large family can be a private form of Social Security. The more children a family has, the more family members there will be to provide for the parents in old age. Poor public health conditions may actually enhance fertility. If each child has a small chance for survival to adulthood, more births are required to produce a given-sized family.OutlineI. Economic Growth FactsA. Pre-1800: Constant Per Capita Income across Time and SpaceB. Post-1800: Sustained Growth in the Rich CountriesC. High I nvestment ↔ High Standard of LivingD. High Population Growth ↔ Low Standard of LivingE. Divergence of Per Capita Incomes: 1800–1950F. No Conditional Convergence amongst All CountriesG. Conditional Convergence amongst the Rich CountriesII. The Malthusian ModelA. Production Determined by Labor and Fixed Land SupplyB. Population Growth and Per Capita ConsumptionC. Steady-state Consumption and Population1. Effects of Technological Change2. Effects of Population ControlD. Malthus: Theory and EvidenceIII. Solow’s Model of Exogenous GrowthA. The Representative ConsumerB. The Representative FirmC. Competitive EquilibriumD. Steady-State Growth1. The Steady-State Path2. Adjustment toward EquilibriumE. Savings and Growth1. Equilibrium Effects2. The Golden Rule: K MP n d =+F. Labor Force Growth and Output Per CapitaG. Total Factor Productivity and Output Per CapitaH. Solow: Theory and Evidence54 Williamson • Macroeconomics, Third EditionIV. Growth AccountingA. Solow ResidualsB. The Productivity Slowdown1. Measurement of Services2. The Relative Price of Energy3. Costs of Adopting New TechnologyC. Cyclical Properties of Solow ResidualsTextbook Question SolutionsQuestions for Review1. In exogenous growth models, growth is caused in the model by forces not explained by the modelitself. Endogenous growth models examine the economic factors that cause growth.2. Pre-1800: Constant Per Capita Income across Time and SpacePost-1800: Sustained Growth in the Rich CountriesHigh Investment ↔ High Standard of LivingHigh Population Growth ↔ Low Standard of LivingDivergence of Per Capita Incomes: 1800–1950No Conditional Convergence amongst All CountriesConditional Convergence amongst the Rich Countries3. An increase in total factor productivity increases the size of the population, but has no effect on theequilibrium level of consumption per capita.4. Only a downward shift in the population growth function can increase the standard of living.5. Malthu’s model is quite successful in explaining economic growth prior to the industrial revolution.Malthu’s model has little relevance for more recent growth experience.6. In the steady state, all variables stay constant: per capita capital, output, consumption, savings. Also,this steady state is stable: whatever the initial capital (except zero), the economy will converge to this steady state.7. With an increase in the saving rate, it becomes possible to sustain a higher level of per capita capital,and thus higher output and consumption. With an increase in the population rate, the contraryhappens, as one needs to provide more newborns with the going per capita capital. A higher total factor productivity improves all per capita variables in the steady state.8. To maximize steady-state per capita consumption, the saving rate must be such that the marginalproduct of capital (the slope of the per capita production function) equals the population growth rate plus the depreciation rate.9. The Malthusian model gave no way out of misery, except for measures that reduce the population.Even technological advances would not raise the standard of living. The Solow model shows that it is possible to obtain a stable standard of living with growing population. And if total factor productivity increases, one can even obtain improvements in the standard of living despite population growth.Chapter 6 Economic Growth: Malthus and Solow 55 10. The Cobb-Douglas production function permits a simple decomposition of economic growth into itscomponent sources.11. In a competitive equilibrium, the parameter a is equal to the share of capital income in total income.12. The Solow residual measures increases in real GDP that are not accounted for by increases in capitaland labor. The Solow residual is highly procyclical as it explains the great majority of the cyclical component in GDP.13. The productivity slowdown could be explained by underestimates of output in the growing servicessector, increases in the relative price of energy, and the costs of adopting new technologies.14. American workers then knew how to incorporate the new technologies, in particular informationtechnology. These efficiency gains may have been realized by 2000, which explains the newslowdown, along with higher energy prices.15. Growth in capital, employment, and total factor productivity account for growth in GDP.16. During this period, growth in these countries was much larger than average. Growth rates for thesecountries were about three times as fast as growth in the United States. However, most of this growth can be attributed to increases in the capital stocks in these countries, and such rapid rates of growth of capital cannot be sustained for long periods of time.Problems1. The amount of land increases, and, at first, the size of the population is unchanged. Therefore,consumption per capita increases. However, the increase in consumption per capita increases the population growth rate, see the figure below. In the steady state, neither *c nor *l are affected by the initial increase in land. This fact can be discerned by noting that there will be no changes in either of the panels of Figure 6.8 in the textbook.56 Williamson • Macroeconomics, Third Edition2. A reduction in the death rate increases the number of survivors from the current period who will stillbe living in the future. Therefore, such a technological change in public health shifts the function ()g cupward. In problem #1 there were no effects on the levels of land per capita and consumption per capita. In this case, the ()g c function in the bottom figure below shifts upward. Equilibriumconsumption per capita decreases. From the top figure below, we also see that the decrease inconsumption per capita requires a reduction in the equilibrium level of land per capita. The size of the population has increased, but the amount of available land is unchanged.Chapter 6 Economic Growth: Malthus and Solow 57 3. For the marginal product of capital to increase at every level of capital, the shift in the productionfunction is equivalent to an increase in total factor productivity.(a) The original and new production functions are depicted in the figures below.(b) Equilibrium in the Solow model is at the intersection of ()n d k+szf k with the line segment ().The old and new equilibria are depicted in the bottom panel of the figure above. The newequilibrium is at a higher level of capital per capita and a higher level of output per capita.(c) For a given savings rate, more effective capital implies more savings, and in the steady state thereis more capital and more output. However, if the increase in the marginal product of capital were local, in the neighborhood of the original equilibrium, there would be no equilibrium effects. A twisting of the production function around its initial point does not alter the intersection point.4. An increase in the depreciation rate acts in much the same way as an increase in the populationgrowth rate. More of current savings is required just to keep the amount of capital per capita constant.In equilibrium output per capita and capital per capita decrease.58 Williamson • Macroeconomics, Third Edition5. A destruction of capital.(a) The long-run equilibrium is not changed by an alteration of the initial conditions. If the economystarted in a steady state, the economy will return to the same steady state. If the economy wereinitially below the steady state, the approach to the steady state will be delayed by the loss ofcapital.(b) Initially, the growth rate of the capital stock will exceed the growth rate of the labor force. Thefaster growth rate in capital continues until the steady state is reached.(c) The rapid growth rates are consistent with the Solow model’s predictions about the likelyadjustment to a loss of capital.6. A reduction in total factor productivity reduces the marginal product of capital. The golden rule levelof capital per capita equates the marginal product of capital with .n d + Therefore, for given ,n d + the golden rule amount of capital per capita must decrease as in the figure below. Therefore the golden rule savings rate must decrease.7. Government spending in the Solow model.(a) By assumption, we know that T = G, and so we may write:()(1)(1)K's Y G d K sY gN d K =−+−=−+−Now divide by N and rearrange as:(1)()(1)k'n szf k sg d k +=−+−Divide by (1 + n ) to obtain:()(1)(1)(1)(1)szf k sg d k k'n n n −=−++++Chapter 6 Economic Growth: Malthus and Solow 59Setting k = k ′, we find that:**()().szf k sg n d k =++This equilibrium condition is depicted in the figure below.(b) The two steady states are also depicted in the figure above.(c) The effects of an increase in g are depicted in the bottom panel of the figure above. Capital percapita declines in the steady state. Steady-state growth rates of aggregate output, aggregate consumption, and investment are all unchanged. The reduction in capital per capita isaccomplished through a temporary reduction in the growth rate of capital.8. The golden rule quantity of capital per capita, *,k is such that *().K MP zf k n d ′==+ A decrease in the population growth rate, n , requires a decrease in the marginal product of capital. Therefore, thegolden rule quantity of capital per capita must increase. The golden rule savings rate may either increase or decrease.60 Williamson • Macroeconomics, Third Edition9. (a) First, we need to determine how bN evolves over time:(bN )′ = (1 + f )(1 + n ) bNThen we just need to redo the analysis of the competitive equilibrium and the steady state as inthe book, replacing every N by bN , every (1 + n ) by (1 + f )(1 + n ), and every n by f + n . The new steady-state per efficiency unit capital is then******()(1)(1)(1)(1)(1)szf k d k k f n f n −=+++++ All aggregate variables then grow at the rate of f + n , while per capita aggregates grow at therate f .(b) An increase in f increases the growth rate of per capita income by the same amount, as f is itsgrowth rate. This happens because the exogenous growth in b raises instant capital and income for everyone without a need to invest in capital.10. Production linear in capital:()()Y K z zf k f k k N N==⇒= (a) Recall Equation (20) from the text, and replace ()f k with k to obtain:+−=+((1))(1)sz d k'k n Also recall that 11 and .Y Y Y'zk k k'N z N z N'=⇒== Therefore: ((1))(1)Y'sz d Y N'n N+−=+ As long as((1))1,(1)sz d n +−>+ per capita income grows indefinitely. (b) The growth rate of income per capita is therefore: ((1))1(1)()(1)Y'Y sz d N'N g Y n Nsz n d n −+−==−+−+=+ Obviously, g is increasing in s .(c) This model allows for the possibility of an ever-increasing amount of capital per capita. In theSolow model, the fact that the marginal product of capital is declining in capital is the key impediment to continual increases in the amount of capital per capita.Chapter 6 Economic Growth: Malthus and Solow 6111. Solow residual calculations.(a) To calculate the Solow residuals, we apply the formula, 0.360.64ˆˆˆˆ/,zY K N = to the values in the provided table. Adding a new column for these values, we obtain:Year ˆY ˆK ˆN ˆz 1995 8031.7 25487.3 124.9 9.4781996 8328.9 26222.3 126.7 9.6401997 8703.5 27018.1 129.6 9.8231998 9066.9 27915.9 131.5 10.0191999 9470.3 28899.9 133.5 10.2362000 9817.0 29917.1 136.9 10.3122001 9890.7 30793.4 136.9 10.2822002 10048.8 31599.6 136.5 10.3692003 10301.0 32426.2 137.7 10.4722004 10703.5 33304.9 139.2 10.7032005 11048.6 34191.7 141.7 10.820(b) Next, we compute the percentage changes in each of the table entries. These values arepresented in the table below.Year ˆˆY Y Δ/ (%) ˆˆK K Δ/ (%) ˆˆN N Δ/ (%) ˆˆzz Δ/ (%) 1996 3.70 2.88 1.44 1.71 1997 4.50 3.03 2.29 1.901998 4.18 3.32 1.47 2.001999 4.45 3.52 1.52 2.172000 3.66 3.52 2.55 0.742001 0.75 2.93 0.00 −0.292002 1.60 2.62 −0.29 0.852003 2.51 2.62 0.88 0.992004 3.91 2.71 1.09 2.212005 3.22 2.66 1.80 1.0962 Williamson • Macroeconomics, Third EditionTo compare the contributions to growth, we need to compare the magnitudes,ˆˆˆˆ0.36(/),0.64(/),KKNN ΔΔ and ˆˆ/.z z Δ These values are presented in the table below.Year ˆˆ0.36(Δ/K K) (%) ˆˆ0.64(Δ/N N)(%) ˆˆz z Δ/ (%)1996 1.04 0.92 1.711997 1.09 1.46 1.901998 1.20 0.94 2.001999 1.27 0.97 2.172000 1.27 1.63 0.742001 1.05 0.00 −0.292002 0.94 −0.19 0.852003 0.94 0.56 0.992004 0.98 0.70 2.212005 0.96 1.15 1.09Most often, when output is growing, the biggest contribution to growth comes from increases intotal factor productivity. In 1991 and in 2001, both bad years for growth, total factor productivity decreased. In the other years, growth in total factor productivity is usually the largest contributor to growth, while increases in capital and labor equally share the role of the leading cause of growth in the other years. In the later years, capital growth has come to be relatively more important than in the early years.。
宏观经济学 斯蒂芬威廉森chap06
Macroeconomics, 3e (Williamson)Chapter 6 E conomic Growth: Malthus and Solow1) I f changes in economic policy could cause the growth rate of real GDP to increase by 1% peryear for 100 years, then GDP would be ________ % higher after 100 years than it would havebeen otherwise.A) 1.3B) 2.0C) 2.7D) 3.8Answer: CQuestion Status: P revious Edition2) I n an exogenous growth model, growth is caused byA) c apital accumulation.B) g overnment policies.C) h uman capital accumulation.D) f orces that are not explained by the model itself.Answer: DQuestion Status: P revious Edition3) T he idea that an improvement in technology causes an increase in population but causes noincrease in the average standard of living is attributed toA) A dam Smith.B) T homas Malthus.C) R obert Solow.D) M ilton Friedman.Answer: BQuestion Status: P revious Edition4) T he Malthusian model performs poorly in explaining economic growth after theA) F rench Revolution.B) A merican Revolution.C) I ndustrial Revolution.D) B io-technology Revolution.Answer: CQuestion Status: P revious Edition5) T he Solow model emphasizes the role of which of the following factors of production?A) l andB) l aborC) c apitalD) n atural resourcesAnswer: CQuestion Status: P revious Edition6) B efore the Industrial Revolution, standards of living differedA) g reatly over time and across countries.B) l ittle over time, but differed greatly across countries.C) g reatly over time, but differed little across countries.D) l ittle over time and across countries.Answer: DQuestion Status: P revious Edition7) R ecent evidence suggests that output per worker isA) p ositively related to both the rate of investment and to the rate of population growth.B) p ositively related to the rate of investment and negatively related to the rate ofpopulation growth.C) n egatively related to the rate of investment and positively related to the rate ofpopulation growth.D) n egatively related to both the rate of investment and to the rate of population growth.Answer: BQuestion Status: P revious Edition8) T here is evidence that income per worker is converging inA) t he richest countries and the poorest countries.B) t he richest countries, but not the poorest countries.C) t he poorest countries, but not the richest countries.D) n either the richest nor the poorest countries.Answer: BQuestion Status: P revious Edition9) C onditional convergence means thatA) t he distance between poor and rich countries increases.B) t he distance between poor and rich countries stays the same.C) t he distance between poor and rich countries decreases.D) t here is no systematic pattern in how poor and rich countries grow.Answer: CQuestion Status: N ew10) F or conditional convergence to hold, it is required thatA) p oor countries grow.B) p oor countries grow faster and faster.C) p oor countries grow faster than rich countries.D) p oor countries become richer than currently rich countries.Answer: CQuestion Status: N ew11) C onditional convergence means thatA) p oorer countries have higher growth rates.B) p oorer countries have lower growth rates.C) p oorer countries have very diverse growth rates.D) p oorer countries have uniform growth rates.Answer: AQuestion Status: N ew12) I n the Malthusian model, the population growth rate isA) e xogenous.B) p ositively related to consumption per worker.C) n egatively related to consumption per worker.D) a ssumed to be constant.Answer: BQuestion Status: P revious Edition13) T he Malthusian model emphasizes fixity in which of the following factors of production?A) l aborB) l andC) e nergyD) n one of the aboveAnswer: BQuestion Status: P revious Edition14) I n the Malthusian model, an improvement in the technology of growing food is likely toA) i ncrease the equilibrium size of the population and increase the equilibrium level ofconsumption per worker.B) i ncrease the equilibrium size of the population and decrease the equilibrium level ofconsumption per worker.C) i ncrease the equilibrium size of the population and have no effect on the equilibriumlevel of consumption per worker.D) h ave no effect on the equilibrium size of the population and increase the equilibriumlevel of consumption per worker.Answer: CQuestion Status: P revious Edition15) T he Malthusian model predicts thatA) p opulation will keep increasing.B) t he standard of living will keep increasing.C) h ealth improvements increase the standard of living.D) p opulation control improves the standard of living.Answer: DQuestion Status: N ew16) I n a Malthusian world, why is misery recurrent?A) T he marginal returns of capital are decreasing.B) F ertility is endogenous.C) O utput is increasing in labor.D) M ortality depends on the standard of living.Answer: DQuestion Status: N ew17) I n a Malthusian world, what would improve the standard of living permanently?A) a warB) a new medical drugC) b irth controlD) d emocracyAnswer: CQuestion Status: N ew18) I n a Malthusian world, what would improve the standard of living temporarily?A) a warB) a new virusC) b irth controlD) d emocracyAnswer: AQuestion Status: N ew19) I n the Malthusian model, state-mandated population control policies are likely toA) d ecrease the equilibrium size of the population and increase the equilibrium level ofconsumption per worker.B) d ecrease the equilibrium size of the population and have no effect on the equilibriumlevel of consumption per worker.C) h ave no effect on the equilibrium size of the population and increase the equilibriumlevel of consumption per worker.D) h ave no effect on either the equilibrium size of the population or the equilibrium levelof consumption per worker.Answer: AQuestion Status: P revious Edition20) I n the Malthusian model, improvements in health care lead toA) h igher population and higher per-capita production.B) h igher population and lower per-capita production.C) l ower population and higher per-capita production.D) l ower population and lower per-capita production.Answer: BQuestion Status: N ew21) I f an epidemic hits a Malthusian economy, the immediate consequence isA) a n increase in the standard of living.B) a reduction in the standard of living.C) n o change in the standard of living.D) d ependent on the population growth rate.Answer: AQuestion Status: N ew22) I f an epidemic hits a Malthusian economy, the long-term consequence isA) a n increase in the standard of living.B) a reduction in the standard of living.C) n o change in the standard of living.D) d ependent on the population growth rate.Answer: CQuestion Status: N ew23) I n a Malthusian world, what events would improve temporarily the standard of living, asmeasured by output per capita?A) a peace keeping missionB) a n increase in violent crimeC) a new mutation of germsD) a new sewer systemAnswer: BQuestion Status: N ew24) I n a Malthusian world, what events would improve permanently the standard of living, asmeasured by output per capita?A) a peace keeping missionB) a n increase in violent crimeC) a new mutation of germsD) a new sewer systemAnswer: CQuestion Status: N ew25) I n more modern times as opposed to the times of Malthus, higher standards of living appeartoA) d ecrease death rates and increase birth rates.B) d ecrease death rates and also decrease birth rates.C) d ecrease death rates and have no effect on birth rates.D) h ave had effects on neither death rates nor birth rates.Answer: BQuestion Status: P revious Edition26) M althus was too pessimistic because he did not foresee the effects ofA) e ver increasing amounts of land for cultivation.B) i ncreases in the capital stock and the effects of such increases on production.C) i mproved nutrition and health care.D) i mproved family planning practices.Answer: BQuestion Status: P revious Edition27) T he Solow residual attempts to measure the amount of output not explained byA) t echnological progress.B) t he direct contribution of labor and capital.C) e conomic projections.D) t he amount of a nation's human capital.Answer: BQuestion Status: P revious Edition28) G rowth accounting, popularized by Robert Solow, attempts to attribute a change inaggregate outputA) t o its most important single cause.B) s eparately between changes in government policy and changes in total factorproductivity.C) s eparately between changes in total factor productivity and changes in the supplies offactors of production.D) s eparately between changes in the supplies of factors of production and changes ingovernment policy.Answer: CQuestion Status: P revious Edition29) For the production function, Y = zK 0.36N 0.64, if measured output is, ˆYmeasured capital input is ˆK, and measured labor input is ˆN , then the Solow residual would be equal to A) 0.360.64ˆˆˆK N Y. B) 0.360.64ˆˆK N× ˆY . C) 0.640.36ˆˆN K× ˆY . D) 0.360.64ˆˆˆY K N. Answer: DQuestion Status: P revious Edition30) A ll of the following increase total factor productivity exceptA) n ew inventions.B) m ore capital.C) n ew management techniques.D) f avorable changes in government regulations.Answer: BQuestion Status: P revious Edition31) W hich of the following increases total factor productivity?A) i nvestment in machineryB) a harsh winterC) b etter access to creditD) n ew production proceduresAnswer: DQuestion Status: N ew32) G rowth in the Solow residual was slowest in theA) 1950s.B) 1960s.C) 1970s.D) 1980s.Answer: CQuestion Status: P revious Edition33) G rowth in the Solow residual was fastest in theA) 1950s.B) 1960s.C) 1970s.D) 1980s.Answer: BQuestion Status: P revious Edition34) O ne plausible explanation of the U.S. productivity slowdown starting in 1973 is that it is anartifact of mismeasurement. This explanation would require that production ofA) g oods is underestimated.B) g oods is overestimated.C) s ervices is underestimated.D) s ervices is overestimated.Answer: CQuestion Status: P revious Edition35) O ne plausible explanation of the U.S. productivity slowdown starting in 1973 is that it was aresult of the increase in the relative price of energy. This explanation would require that, in light of higher energy costs, theA) c apital stock is overestimated.B) c apital stock is underestimated.C) l abor force is overestimated.D) l abor force is underestimated.Answer: AQuestion Status: P revious Edition36) O ne plausible explanation of the U.S. productivity slowdown starting in 1973 is that it wasthe result of the time needed to adapt to new technology. This explanation would require thatA) w orkers withdraw from the labor force to learn about the new technology.B) a large number of new entrants be attracted to the labor force.C) m anagers be reluctant to adopt changes.D) w orkers time at their jobs be diverted from production to learning the technology.Answer: DQuestion Status: P revious Edition37) P ercentage deviations from trend in the Solow residual areA) u nrelated to the business cycle.B) p rocyclical and smaller than percentage deviations from trend in GDP.C) p rocyclical and have about equal magnitude as percentage deviations from trend inGDP.D) p rocyclical and larger than percentage deviations from trend in GDP.Answer: CQuestion Status: P revious Edition38) T he biggest contribution to real U.S. GDP growth in the 1970s was due to growth inA) t otal factor productivity.B) t he capital stock.C) t he labor force.D) b oth the capital stock and the labor force.Answer: DQuestion Status: P revious Edition39) T he biggest contribution to real GDP growth in the "East Asian Tigers" during the period1966-1991 was due to growth inA) t otal factor productivity.B) t he capital stock.C) t he labor force.D) i nternational trade.Answer: BQuestion Status: P revious Edition40) T he per -worker production function relates output per workerA) t o capital per worker.B) t o the participation rate.C) t o production per worker.D) i n different countries.Answer: AQuestion Status: P revious Edition41) W e can express the per-worker production function as a function of only per-worker capitalthanks toA) t he decreasing marginal return of capital.B) t he decreasing marginal return of labor.C) t he constant returns to scale.D) t he impatience of households.Answer: CQuestion Status: N ew42) T he slope of the output per worker function is equal to theA) m arginal product of capital.B) m arginal product of labor.C) s avings rate.D) g rowth rate of the population.Answer: AQuestion Status: P revious Edition43) I n Solow's model of economic growth, suppose that s represents the savings rate, zrepresents total factor productivity, k represents the level of capital per worker, and f(k) represents the per-worker production function. Also suppose that n represents thepopulation growth rate and d represents the depreciation rate of capital. The equilibrium level of capital per worker, k *, will satisfy the equationA) s zf(k*) = (n + d)k*. B) = (n + d )f (k*).C) nf(k *) = *()sk s d +. D) f (k*) =()s n d +k *. Answer: AQuestion Status: P revious Edition44) T he saving rate has the following characteristic in Solow's exogenous growth modelA) i t increases with output.B) i t first decreases, then increases with output.C) i t first increases, then decreases with output.D) i t is constant.Answer: DQuestion Status: N ew45) I n Solow's exogenous growth model, the principal obstacle to continuous growth in outputper capita is due toA) t he declining marginal product of labor.B) t he declining marginal product of capital.C) l imits in the ability of government policymakers.D) t oo little savings.Answer: BQuestion Status: P revious Edition46) I n Solow's exogenous growth model, the economy reaches a stable steady state becauseA) t he marginal return of capital is decreasing.B) c apital is growing at a constant rate.C) t he substitution effect is stronger than the income effect.D) c onditional convergence holds.Answer: AQuestion Status: N ew47) I n the steady state of Solow's exogenous growth model, an increase in the savings rateA) i ncreases output per worker and increases capital per worker.B) i ncreases output per worker and decreases capital per worker.C) d ecreases output per worker and increases capital per worker.D) d ecreases output per worker and decreases capital per worker.Answer: AQuestion Status: P revious Edition48) W hich of the following is not a feature of the steady state in Solow's exogenous growthmodel?A) T he capital/output ratio is steady.B) C apital grows continuously.C) C onsumption per worker is steady.D) T otal saving is steady.Answer: DQuestion Status: N ew49) I f the population growth rate increases by the same percentage points as the depreciationrate, what happens to the steady-state, per-worker output in Solow's exogenous growth model?A) I t increases.B) I t decreases.C) I t does not change.D) I t cannot exist anymore.Answer: BQuestion Status: N ew50) I f the population growth rate increases by the same percentage points as the depreciationrate decreases, what happens to the steady-state, per-worker consumption in Solow'sexogenous growth model?A) I t increases.B) I t decreases.C) I t does not change.D) I t cannot exist anymore.Answer: CQuestion Status: N ew51) I n Solow's exogenous growth model, the steady-state growth rate of capital can be increasedbyA) h igher population growth.B) h igher depreciation rate.C) h igher saving rate.D) h igher interest rate.Answer: AQuestion Status: N ew52) T he Golden Rule of capital accumulation maximizes the steady-state level ofA) o utput per worker.B) c apital per worker.C) c onsumption per worker.D) i nvestment per worker.Answer: CQuestion Status: P revious Edition53) I n the Golden Rule steady state, the marginal product of capital is equal to theA) s avings rate plus the population growth rate.B) p opulation growth rate plus the depreciation rate.C) d epreciation rate plus the savings rate.D) s avings rate divided by the marginal product of labor.Answer: BQuestion Status: P revious Edition54) W ith the Golden Rule,A) s avings maximize output.B) s avings maximize consumption.C) s avings minimize costs.D) s avings optimize the population level.Answer: BQuestion Status: N ew55) T he Golden Rule says thatA) o ne should save as much as possible.B) o ne should save as little as possible.C) o ne should save something between A and B.D) s avings are irrelevant.Answer: CQuestion Status: N ew56) I n the steady state of Solow's exogenous growth model, an increase in the growth rate oflabor forceA) i ncreases output per worker and increases capital per worker.B) i ncreases output per worker and decreases capital per worker.C) d ecreases output per worker and increases capital per worker.D) d ecreases output per worker and decreases capital per worker.Answer: DQuestion Status: P revious Edition57) I n the steady state of Solow's exogenous growth model, an increase in total factorproductivityA) i ncreases output per worker and increases capital per worker.B) i ncreases output per worker and decreases capital per worker.C) d ecreases output per worker and increases capital per worker.D) d ecreases output per worker and decreases capital per worker.Answer: AQuestion Status: P revious Edition。
黎诣远《宏观经济学》(第3版)笔记(2.3第6章 劳动就业)
黎诣远《宏观经济学》（第3版）第6章 劳动就业跨考网独家整理最全经济学考研真题，经济学考研课后习题解析资料库，您可以在这里查阅历年经济学考研真题，经济学考研课后习题，经济学考研参考书等内容，更有跨考考研历年辅导的经济学学哥学姐的经济学考研经验，从前辈中获得的经验对初学者来说是宝贵的财富，这或许能帮你少走弯路，躲开一些陷阱。
以下内容为跨考网独家整理，如您还需更多考研资料，可选择经济学一对一在线咨询进行咨询。
一、就业与失业1．失业的测定（1）失业人口根据国际劳工组织的定义，失业人口是指一定劳动年龄以上，有劳动能力，在规定的调查时间范围内没有职业或工作时间、没有达到规定标准，正在寻找有报酬的工作并已在就业机构进行了登记的人员。
下列情况之一属于失业者：①工作合同已终结或暂时终止，正在寻找有报酬工作的人；②从未受雇工作，正在寻找有报酬工作的人；③已退休但在一定时期内仍然能够工作，并正在寻找有报酬工作的人；④目前尚无工作，但已安排好在某一时期开始从事新工作的人；⑤暂时被解雇而又没有薪金的人。
（2）劳动力人口失业的统计指标是失业率，指失业人数占劳动力总数的比例。
失业率实际上是指失业人口与民用劳动力人口之比，可用公式表示为：100%100%+=⨯=⨯失业人口失业人口失业率劳动力人口就业人口失业人口2．失业的类型（1）按失业的原因划分①摩擦性失业摩擦性失业是指由于劳动力的正常流动所导致的暂时失业。
摩擦性失业在任何时期都存在，即使在经济高速增长时期也不会消失。
②季节性失业季节性失业是指由于某些行业生产经营活动的季节性变化而导致劳动力市场失衡造成的失业。
这些行业的生产季节性是由自然条件决定的，表现为生产经营有淡季和旺季之分，难以改变。
因而，这种失业也是正常的。
③结构性失业结构性失业是指由于经济结构变化和产业兴衰转移，劳动力难以适应新的工作岗位要求而造成的失业。
结构性失业与摩擦性失业的共同点是职位空缺与失业并存，但结构性失业更强调劳动供求的结构失衡，失业的持续时间更长，而且集中在经济落后地区。
威廉森宏观经济学有投资的实际跨期模型PPT课件
原文：As we show, a firm invests more the lower its current capital stock, the higher its expected future total factor productivity, and the lower the real interest rate.
9பைடு நூலகம்19
企业的劳动需求
Copyright © 2012 蔡晓陈. All rights reserved.
9-20
全要素生产率或资本存量变化时 的劳动需求需求移动
Copyright © 2012 蔡晓陈. All rights reserved.
9-21
Representative代表性企业投资决 策
9-11
实际利率提高对当期劳动供给 的影响（闲暇的跨期替代效应）
Copyright © 2012 蔡晓陈. All rights reserved.
9-12
一生财富增加对当期劳动供给 曲线的影响
Copyright © 2012 蔡晓陈. All rights reserved.
9-13
当前消费需求（参见第八章）
4、第三版，P300，式(10.15)应改为
A P Y P I P H ( X f) B f( 1 R ) B f
5、第三版，P300，式(10.16)应改为
A P Y P X f P H (X f)
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
9-26
第三节 政府
• 政府 ☆假设
1、当期购买G单位的消费品，未来购买G’单位的消费品； 2、当期的总税收是T，未来的总税收是T’； 3、政府当期发行B单位的政府债券；
宏观经济学-课后思考题答案_史蒂芬威廉森003
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.。
威廉森《宏观经济学》(第3版)配套题库章节题库 第6章 经济增长：马尔萨斯和索洛【圣才出品】
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圣才电子书 十万种考研考证电子书、题库视频学习平台
步，人均消费可写为：
【答案】×
【解析】假定资本的边际报酬递增，则 f k 0 ，可能存在一种情况即实际投资始终
大于持平投资，人均资本存量将不断增大，经济没有稳定状态。
12．根据索洛增长模型，中国的稳态人均收入增长率高于美国的稳态人均收入增长率。 （）
【答案】× 【解析】储蓄率不具有增长效应，虽然中国的储蓄率高于美国，但这仅影响稳定状态的 人均收入水平，而不影响人均收入水平的增长率，因此中国人均收入增长率并不一定高于美 国。
2．经济增长黄金律
答：资本的黄金律水平是指稳定状态人均消费最大化所对应的人均资本水平，由经济学
家费尔普斯于 1961 年提出。他认为如果一个经济的发展目标是使稳态人均消费最大化，那
么在技术和劳动增长率固定不变时，稳态人均资本量的选择应使资本的边际产品等于劳动的
增长率。用方程表示为：
f k* n
上述结论可以用图 6-1 来加以论证。如图 6-1 所示，应选择 k* ，这时稳态的人均消费
6．根据索洛增长模型，无论经济开始时处在什么位置，最终它都将调整至稳态。（ ） 【答案】√
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圣才电子书 十万种考研考证电子书、题库视频学习平台
【解析】假定经济的初始资本水平低于稳态，那么其投资水平大于折旧量，随着时间的 推移，资本存量将一直上升到稳定状态为止。当经济的初始资本水平高于稳态，那么投资小 于折旧，资本的磨损快于更替，资本存量将一直减少到稳态水平为止。
高鸿业 三版 宏观经济学 课件 第6章
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人生得意须尽欢，莫使金樽空对月。08:54:5508:54:5508:5411/21/2020 8:54:55 AM
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安全象只弓，不拉它就松，要想保安 全，常 把弓弦 绷。20.11.2108:54:5508:54Nov-2021-Nov-20
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加强交通建设管理，确保工程建设质 量。08:54:5508:54:5508:54Saturday, November 21, 2020
总需求总供给模型含有的四个方程如下：
产品市场均衡条件： i（r）+ g = s（y - t）+ t
货币市场均衡条件：
M
P
= L1（y）+ L2（r）
劳动市场均衡条件： f（N）=
M
P
；
h（N）=
M
P
短期总量生产函数： y = y（N，K）
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树立质量法制观念、提高全员质量意 识。20.11.2120.11.21Saturday, November 21, 2020
第十七章
总需求—总供给模型
第一节
总 需求曲 线
一、总需求
总需求——是指经济社会对产品和劳务的需求总
量，这一需求总量通常以产出水平来表示。总需求由 消费需求、投资需求、政府需求和国外需求构成。
在不考虑国外需求的情况下，经济社会的总需求是指 价格、收入和其他经济变量在既定条件下，家户部门、 企业部门和政府将要支出的数量。
yf
y
第六节 常规总供给曲线
一、常规总供给曲线 （线性的）
在通常的或常规的情况下，短期总供给曲线位 于两个极端之间。
P
A
C
B
B
E
C
A
宏观经济学-课后思考题答案_史蒂芬威廉森002
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 =+++=−−−=−−+=。
宏观经济学-课后思考题答案_史蒂芬威廉森004
Chapter 4Consumer and Firm Behavior: The Work-Leisure Decision and Profit MaximizationTeaching GoalsThe microeconomic approach to macroeconomics stresses the notion that economy-wide events are the result of decisions made by individuals. People work so that they may afford to buy market goods. On the other hand, people generally prefer to work less rather than working more. Although discussions in the popular press often refer to the idea that spending is what drives the economy, an economy cannot produce unless people are willing to work. Therefore, the most basic macroeconomic decision is the decision to choose whether, and how much, to work. Production and willingness to work are intrinsically interconnected.Students often believe that how much a person works is largely determined by the necessities of their circumstances. Students will report that they have to work to survive and pay tuition. Some might point out that some students need not work much or at all because their parents provide more support. However, circumstances need not dictate exactly how much they may choose to work. They may work less if they go to a less costly school. They may sometimes decide to switch to part-time student status and full-time work status if they find a high-paying job. A key message of this chapter is that choice is important and that choice is influenced by changes in circumstances.This chapter demands the mastery of a large body of structure and yet provides little in the way of immediate insights. Students may need frequent assurances that the mastery of this material eventually pays big dividends in providing hope of understanding the phenomenon of business cycles. This is particularly important as this chapter lays critical foundations for the rest of the book: the use of microfoundations in macroeconomics. Students need to be able to justify macroeconomic relationships with microeconomic arguments, like in this chapter. This requires to some extend some boring drills that they will come to appreciate only later. If for many textbooks the strategy is to teach one chapter a week, spend more time on this one, especially if students have not yet mastered intermediate microeconomics. Two key points of this chapter are the concepts of income and substitution effects. Often, students are perplexed at the amount of time spent on this material because nothing in practice is purely an income effect or a substitution effect. However, the two most basic insights of microeconomic analysis are that when we become more well-off we generally want more of everything and that we respond to price incentives at the margin.Classroom Discussion TopicsAsk the students about their work choices and the choices of their parents, friends, and relatives. Does everyone work? Does everyone work the same amount of hours? Then ask the students for examples of the kinds of factors that lead people to work more or less. Try to elicit very specific examples. Thenask the students to categorize these factors that lead to more or less work. Some of these factors are actually the by-products of more complex decision making. For example, if they say that they work more or less because they go to school, point out that going to school is a choice. They may also point to28 Williamson • Macroeconomics, Third Editioncircumstances like whether a married couple has children, and if so, their number and their ages. Point out that these events are also the results of other choices. Then ask the students to try to categorize the remaining factors as being primarily an income effect or a substitution effect. Compare also labor choices across countries, as the Macroeconomics in Action feature, new to the third edition, does.Ask the students to provide examples of factors other than more labor or capital that can allow some countries to be a lot more productive than others. What factors other than growth in capital and labor allow a given economy to produce more (or less) over time? Explain that these are the kinds of factors that we summarize by the concept of total factor productivity. Insist also on the concept of physical capital and what it measures and what it is not.OutlineI. The Representative ConsumerA. Preferences1. Goods: The Consumption Good and Leisure2. The Utility Functiona. More Preferred to Lessb. Preference for Diversityc. Normal Goods3. Indifference Curvesa Downward Slopingb. Convex to the Origin4. Marginal Rate of SubstitutionB. Budget Constraint1. Price-taking Behavior2. The Time Constraint3. Real Disposable Income4. A Graphical RepresentationC. Optimization1. Rational Behavior2. The Optimal Consumption Bundle3. Marginal Rate of Substitution = Relative Price4. A Graphical RepresentationD. Comparative Statics Experiments1. Changes in Dividends and Taxes: Pure Income Effect2. Changes in the Real Wage: Income and Substitution EffectsII. The Representative FirmA. The Production Function1. Constant Returns to Scale2. Monotonicity3. Declining MPN4. Declining MPK5. Changes in Capital and MPN6. Total Factor ProductivityChapter 4 Consumer and Firm Behavior: The Work-Leisure Decision and Profit Maximization 29B. Profit Maximization1. Profits = Total Revenue − Total Variable Costs2. Marginal Product of Labor = Real Wage3. Labor DemandTextbook Question SolutionsQuestions for Review1. Consumers consume an aggregate consumption good and leisure.2. Consumers’ preferences are summarized in a utility function.3. The first property is that more is always preferred to less. This property assures us that a consumptionbundle with more of one good and no less of the other good than any second bundle will always be preferred to the second bundle.The second property is that a consumer likes diversity in his or her consumption bundle. Thisproperty assures us that a linear combination of two consumption bundles will always be preferred to the two original bundles.The third property is that both consumption and leisure are normal goods. This property assures us that an increase in a consumer’s income will always induce the individual to consume more of both consumption and leisure.4. The first property of indifference curves is that they are downward sloping. This property is a directconsequence of the property that more is always preferred to less. The second property ofindifference curves is that they are bowed toward the origin. This property is a direct consequence of consumers’ preference for diversity.5. Consumers maximize the amount of utility they can derive from their given amount of availableresources.6. The optimal bundle has the property that it represents a point of tangency of the budget line with anindifference curve. An equivalent property is that the marginal rate of substitution of leisure forconsumption and leisure is equal to the real wage.7. In response to an increase in dividend income, the consumer will consume more goods and moreleisure.8. In response to an increase in the real value of a lump-sum tax, the consumer will consume less goodsand less leisure.9. An increase in the real wage makes the consumer more well off. As a result of this pure incomeeffect, the consumer wants more leisure. Alternatively, the increase in the real wage induces asubstitution effect in which the consumer is willing to consume less leisure in exchange for working more hours (consuming less leisure). The net effect of these two competing forces is theoretically ambiguous.10. The representative firm seeks to maximize profits.30 Williamson • Macroeconomics, Third Edition11. As the amount of labor is increased, holding the amount of capital constant, each worker gets asmaller share of the fixed amount of capital, and there is a reduction in each worker’s marginalproductivity.12. An increase in total factor productivity shifts the production function upward.13. The representative firm’s profit is equal to its production (revenue measured in units of goods) minusits variable labor costs (the real wage times the amount of labor input). A unit increase in labor input adds the marginal product of labor to revenue and adds the real wage to labor costs. The amount of labor demand is that amount of labor input that equates marginal revenue with marginal labor costs.This quantity of labor, labor demand, can simply be read off the marginal product of labor schedule.Problems1. Consider the two hypothetical indifference curves in the figure below. Point A is on both indifferencecurves, I1 and I2. By construction, the consumer is indifferent between A and B, as both points are onI 2. In like fashion, the consumer is indifferent between A and C, as both points are on I1. But atpoint C, the consumer has more consumption and more leisure than at point B. As long as the consumer prefers more to less, he or she must strictly prefer C to A. We therefore contradict the hypothesis that two indifference curves can cross.Chapter 4 Consumer and Firm Behavior: The Work-Leisure Decision and Profit Maximization 312. u al bC =+(a) To specify an indifference curve, we hold utility constant at u . Next rearrange in the form:u a C l b b=− Indifference curves are therefore linear with slope, −a /b , which represents the marginal rate ofsubstitution. There are two main cases, according to whether /a b w > or /.a b w < The top panelof the left figure below shows the case of /.a b w < In this case the indifference curves are flatterthan the budget line and the consumer picks point A, at which 0l = and .C wh T π=+− Theright figure shows the case of /.a b w > In this case the indifference curves are steeper than thebudget line, and the consumer picks point B, at which l h = and .C T π=− In the coincidentalcase in which /,a b w = the highest attainable indifference curve coincides with the indifference curve, and the consumer is indifferent among all possible amounts of leisure and hours worked.(b) The utility function in this problem does not obey the property that the consumer prefersdiversity, and is therefore not a likely possibility.(c) This utility function does have the property that more is preferred to less. However, the marginalrate of substitution is constant, and therefore this utility function does not satisfy the property ofdiminishing marginal rate of substitution.32 Williamson • Macroeconomics, Third Edition3. When the government imposes a proportional tax on wage income, the consumer’s budget constraintis now given by:(1)(),C w t h l T π=−−+−where t is the tax rate on wage income. In the figure below, the budget constraint for t = 0, is FGH.When t > 0, the budget constraint is EGH. The slope of the original budget line is –w , while the slope of the new budget line is –(1 – t )w . Initially the consumer picks the point A on the original budget line. After the tax has been imposed, the consumer picks point B. The substitution effect of theimposition of the tax is to move the consumer from point A to point D on the original indifference curve. The point D is at the tangent point of indifference curve, I 1, with a line segment that is parallel to EG. The pure substitution effect induces the consumer to reduce consumption and increase leisure (work less).The tax also makes the consumer worse off, in that he or she can no longer be on indifference curve,I 1, but must move to the less preferred indifference curve, I 2. This pure income effect moves the consumer to point B, which has less consumption and less leisure than point D, because bothconsumption and leisure are normal goods. The net effect of the tax is to reduce consumption, but the direction of the net effect on leisure is ambiguous. The figure shows the case in which the substitution effect on leisure dominates the income effect. In this case, leisure increases and hours worked fall. Although consumption must fall, hours worked may rise, fall, or remain the same.4. The increase in dividend income shifts the budget line upward. The reduction in the wage rate flattensthe budget line. One possibility is depicted in the figures below. The original budget constraint HGL shifts to HFE. There are two income effects in this case. The increase in dividend income is a positive income effect. The reduction in the wage rate is a negative income effect. The drawing in the topfigure shows the case where these two income effects exactly cancel out. In this case we are left with a pure substitution effect that moves the consumer from point A to point B. Therefore, consumption falls and leisure increases. As leisure increases, hours of work must fall. The middle figure shows a case in which the increase in dividend income, the distance GF, is larger and so the income effect is positive. The consumer winds up on a higher indifference curve, leisure unambiguously increases,Chapter 4 Consumer and Firm Behavior: The Work-Leisure Decision and Profit Maximization 33 and consumption may either increase or decrease. The bottom figure shows a case in which the increase in dividend income, the distance GF, is smaller and so the income effect is negative. The consumer winds up on a lower indifference curve, consumption unambiguously decreases, and leisure may either increase or decrease.34 Williamson • Macroeconomics, Third Edition5. This problem introduces a higher, overtime wage for hours worked above a threshold, q . Thisproblem also abstracts from any dividend income and taxes.(a) The budget constraint is now EJG in the figure below. The budget constraint is steeper for levels ofleisure less than h – q , because of the higher overtime wage. The figure depicts possible choices for two different consumers. Consumer #1 picks point A on her indifference curve, I 1. Consumer #2 picks point B on his indifference curve, I 2. Consumer #1 chooses to work overtime; consumer #2 does not.(b) The geometry of the figure above makes it clear that it would be very difficult to have anindifference curve tangent to EJG close to point J. In order for this to happen, an indifferencecurve would need to be close to right angled as in the case of pure complement. It is unlikely that consumers wish to consume goods and leisure in fixed proportions, and so points like A and Bare more typical. For any other allowable shape for the indifference curve, it is impossible forpoint J to be chosen.(c) An increase in the overtime wage steepens segment EJ of the budget constraint, but has no effecton the segment JG. For an individual like consumer #2, the increase in the overtime wage has no effect up until the point at which the increase is large enough to shift the individual to a point like point A. Consumer #2 receives no income effect because the income effect arises out of a higher wage rate on inframarginal units of work. An individual like consumer #1 has the traditionalincome and substitution effects of a wage increase. Consumer #1 increases her consumption, but may either increase or reduce hours of work according to whether the income effect outweighsthe substitution effect.Chapter 4 Consumer and Firm Behavior: The Work-Leisure Decision and Profit Maximization 356. Lump-sum Tax vs. Proportional Tax. Suppose that we start with a proportional tax. Under theproportional tax the consumer’s budget line is EFH in the figure below. The consumer choosesconsumption, *,C and leisure, *,l at point A on indifference curve I 1. A shift to a lump-sum tax steepens the budget line. The absolute value of the slope of the budget line is (1),t w − and t has fallen to zero. The imposition of the lump-sum tax shifts the budget line downward in a parallel fashion. By construction, the lump-sum tax must raise the same amount of revenue as the proportional tax. The consumer must therefore be able to continue to consume *C of the consumption good and *l ofleisure after the change in tax collection. Therefore, the new budget line must also pass through pointA. The new budget line is labeled LGH in the figure below. With the lump-sum tax, the consumer can do better by choosing point B, on the higher indifference curve, I 2. Therefore, the consumer is clearly better off. We are also assured that consumption will be greater at point B than at point A, and that leisure will be smaller at point B than at point A.7. Leisure represents all time used for nonmarket activities. If the government is now providing forsome of those, like providing free child care, households will take advantage of such a program,thereby allowing more time for other activities, including market work. Concretely, this translates in a change of preferences for households. For the same amount of consumption, they are now willing to work more, or in other words, they are willing to forego some additional leisure. On the figure below, the new indifference curve is labeled I 2. It can cross indifference curve I 1 because preferences, as we measure them here, have changed. The equilibrium basket of goods for the household now shifts from A to B. This leads to reduced leisure (from l *1 to l *2), and thus increased hours worked, and increased consumption (from C *1 to C *2) thanks to higher labor income at the fixed wage.36 Williamson • Macroeconomics, Third Edition8. The firm chooses its labor input, N d , so as to maximize profits. When there is no tax, profits for thefirm are given by(,).d d zF K N wN π=−That is, profits are the difference between revenue and costs. In the top figure on the following page,the revenue function is (,)d zF K N and the cost function is the straight line, wN d . The firm maximizes profits by choosing the quantity of labor where the slope of the revenue function equals the slope of the cost function:.N MP w =The firm’s demand for labor curve is the marginal product of labor schedule in the bottom figure on the following page.With a tax that is proportional to the firm’s output, the firm’s profits are given by:(,)(,)(1)(,),d d d d zF K N wN tzF K N t zF K N π=−−=−where the term (1)(,)d t zF K N − is the after-tax revenue function, and as before, wN d is the costfunction. In the top figure below, the tax acts to shift down the revenue function for the firm and reduces the slope of the revenue function. As before, the firm will maximize profits by choosing the quantity of labor input where the slope of the revenue function is equal to the slope of the cost function, but the slope of the revenue function is (1),N t MP − so the firm chooses the quantity of labor where(1).N t MP w −=In the bottom figure below, the labor demand curve is now (1),N t MP − and the labor demand curve has shifted down. The tax acts to reduce the after-tax marginal product of labor, and the firm will hire less labor at any given real wage.9. The firm chooses its labor input N dso as to maximize profits. When there is no subsidy, profits forthe firm are given by (,).d d zF K N wN π=−That is, profits are the difference between revenue and costs. In the top figure on the following page the revenue function is (,)d zF K N and the cost function is the straight line, wN d . The firm maximizes profits by choosing the quantity of labor where the slope of the revenue function equals the slope of the cost function:.N MP w =The firm’s demand for labor curve is the marginal product of labor schedule in the bottom figure below.With an employment subsidy, the firm’s profits are given by:(,)()d d zF K N w s N π=−−where the term (,)d zF K N is the unchanged revenue function, and (w – s )N d is the cost function. The subsidy acts to reduce the cost of each unit of labor by the amount of the subsidy, s . In the top figure below, the subsidy acts to shift down the cost function for the firm by reducing its slope. As before, the firm will maximize profits by choosing the quantity of labor input where the slope of the revenue function is equal to the slope of the cost function, (t – s ), so the firm chooses the quantity of labor where.N MP w s =−In the bottom figure below, the labor demand curve is now ,N MP s + and the labor demand curve has shifted up. The subsidy acts to reduce the marginal cost of labor, and the firm will hire more labor at any given real wage.10. Minimum Employment Requirement. Below *,N no output is produced. Thereafter, the production function has its usual properties. Such a production function is reproduced in the first two figures below. At high wages, the firm’s cost curve is entirely above the revenue curve, so the firm hires no labor, to prevent incurring losses. Only if the wage rate is less than ˆw will the firms choose to hire anyone. At ˆ,N just as it would in the absence of the constraint. Below ˆ,w w w=the firm chooses*,the labor demand curve is unaffected. The labor demand curve is reproduced in the bottom figure.11. The level of output produced by one worker who works h – l hours is given by(,).s Y zF K h l =−This equation is plotted in the figure below. The slope of this production possibilities frontier is simply .N MP −12. As the firm has to internalize the pollution, it realizes that labor is less effective than it previouslythought. It now needs to hire N (1 + x ) workers where N were previously sufficient. This is qualitatively equivalent to a reduction of z , total factor productivity. The figure below highlights the resulting outcome: the firm now hires fewer people for a given wage and thus its labor demand is reduced.13. 0.30.7Y zK n =(a) 0.7.Y n = See the top figure below. The marginal product of labor is positive and diminishing. (b) 0.72.Y n = See the figures below.(c) 0.30.70.72 1.23.Y n n =≈ See the figures below.(d) See the bottom figure below.−−−−==⇒===⇒===⇒=×≈0.30.30.30.30.31,10.72,1 1.41,220.70.86N N N z K MP n z K MP n z K MP n n。
宏观经济学-课后思考题答案_史蒂芬威廉森006
Chapter 6Economic Growth: Malthus and SolowTeaching GoalsStudents easily take for granted the much more abundant standard of living of today as opposed to 20, 50, or 100 years ago. Sometimes it is easier to remind students of what their ancestors had to do without, rather than simply referring to per capita income levels over time. Recessions come and go, and yet economic growth swamps the lost output we endure during hard times.The typical student begins study of economic growth against the backdrop of the recent growth experience of the United States. The current standard of living in the United States vastly surpasses the current standard of living in most countries and would have been unimaginable anywhere in the world before the advent of the industrial revolution. Until about 1800, the world economy produced little more than a subsistence level of income for any but the richest individuals. Growth in per capita income was nonexistent. The Malthusian model of growth explains the tendency of increases in population to dilute any gains in productivity.The industrial revolution introduced the possibility of sustained growth in per capita income through the accumulation of physical capital. However, growth experience has varied widely around the world. The richer countries have a sustained record of growth. Per capita income in the United States has proceeded at an average rate of about 2% per year. While 2% growth may seem small, it is important for students to realize that such growth transforms into a more than doubling of per capita GDP per generation. Unfortunately, the poorer countries have remained poor. Furthermore, their growth rates have not generally matched growth rates in the richer countries, so that the poor countries fall farther and farther behind. Such differences in standards of living and growth prospects present puzzles that the study of economic growth hopes to solve.Classroom Discussion TopicsGetting students to relate to differences in standards of living can sometimes be difficult. It is easy to take one’s own standard of living for granted. An interesting discussion topic is whether students would be willing to travel back in time to 100 or 200 years ago, if they could be one of the richest people of those earlier times. Would the tradeoff be worthwhile? While students typically stress factors like antiquated view about freedom of choice, and racial and gender issues, try to encourage students to divide their concerns into those that are more economic as opposed to social. Also point out that higher standards of living allow societies to be more concerned about issues of equality when mere survival is no longer precarious.Chapter 6 Economic Growth: Malthus and Solow 53Students often view population growth as the result of cultural factors and personal preferences. Against the abundance of daily living, it is easy to forget economic factors. Ask the students for examples ofeconomic factors that might impact on fertility decisions. The Malthusian model suggests that growth may only be achieved through population control. In the modern economy, the costs of raising children can be formidable, and so there is tendency for such costs to be a disincentive to fertility. Such costs may attribute to the tendency for low fertility rates in advanced economies. In more primitive societies, having a large family can be a private form of Social Security. The more children a family has, the more family members there will be to provide for the parents in old age. Poor public health conditions may actually enhance fertility. If each child has a small chance for survival to adulthood, more births are required to produce a given-sized family.OutlineI. Economic Growth FactsA. Pre-1800: Constant Per Capita Income across Time and SpaceB. Post-1800: Sustained Growth in the Rich CountriesC. High I nvestment ↔ High Standard of LivingD. High Population Growth ↔ Low Standard of LivingE. Divergence of Per Capita Incomes: 1800–1950F. No Conditional Convergence amongst All CountriesG. Conditional Convergence amongst the Rich CountriesII. The Malthusian ModelA. Production Determined by Labor and Fixed Land SupplyB. Population Growth and Per Capita ConsumptionC. Steady-state Consumption and Population1. Effects of Technological Change2. Effects of Population ControlD. Malthus: Theory and EvidenceIII. Solow’s Model of Exogenous GrowthA. The Representative ConsumerB. The Representative FirmC. Competitive EquilibriumD. Steady-State Growth1. The Steady-State Path2. Adjustment toward EquilibriumE. Savings and Growth1. Equilibrium Effects2. The Golden Rule: K MP n d =+F. Labor Force Growth and Output Per CapitaG. Total Factor Productivity and Output Per CapitaH. Solow: Theory and Evidence54 Williamson • Macroeconomics, Third EditionIV. Growth AccountingA. Solow ResidualsB. The Productivity Slowdown1. Measurement of Services2. The Relative Price of Energy3. Costs of Adopting New TechnologyC. Cyclical Properties of Solow ResidualsTextbook Question SolutionsQuestions for Review1. In exogenous growth models, growth is caused in the model by forces not explained by the modelitself. Endogenous growth models examine the economic factors that cause growth.2. Pre-1800: Constant Per Capita Income across Time and SpacePost-1800: Sustained Growth in the Rich CountriesHigh Investment ↔ High Standard of LivingHigh Population Growth ↔ Low Standard of LivingDivergence of Per Capita Incomes: 1800–1950No Conditional Convergence amongst All CountriesConditional Convergence amongst the Rich Countries3. An increase in total factor productivity increases the size of the population, but has no effect on theequilibrium level of consumption per capita.4. Only a downward shift in the population growth function can increase the standard of living.5. Malthu’s model is quite successful in explaining economic growth prior to the industrial revolution.Malthu’s model has little relevance for more recent growth experience.6. In the steady state, all variables stay constant: per capita capital, output, consumption, savings. Also,this steady state is stable: whatever the initial capital (except zero), the economy will converge to this steady state.7. With an increase in the saving rate, it becomes possible to sustain a higher level of per capita capital,and thus higher output and consumption. With an increase in the population rate, the contraryhappens, as one needs to provide more newborns with the going per capita capital. A higher total factor productivity improves all per capita variables in the steady state.8. To maximize steady-state per capita consumption, the saving rate must be such that the marginalproduct of capital (the slope of the per capita production function) equals the population growth rate plus the depreciation rate.9. The Malthusian model gave no way out of misery, except for measures that reduce the population.Even technological advances would not raise the standard of living. The Solow model shows that it is possible to obtain a stable standard of living with growing population. And if total factor productivity increases, one can even obtain improvements in the standard of living despite population growth.Chapter 6 Economic Growth: Malthus and Solow 55 10. The Cobb-Douglas production function permits a simple decomposition of economic growth into itscomponent sources.11. In a competitive equilibrium, the parameter a is equal to the share of capital income in total income.12. The Solow residual measures increases in real GDP that are not accounted for by increases in capitaland labor. The Solow residual is highly procyclical as it explains the great majority of the cyclical component in GDP.13. The productivity slowdown could be explained by underestimates of output in the growing servicessector, increases in the relative price of energy, and the costs of adopting new technologies.14. American workers then knew how to incorporate the new technologies, in particular informationtechnology. These efficiency gains may have been realized by 2000, which explains the newslowdown, along with higher energy prices.15. Growth in capital, employment, and total factor productivity account for growth in GDP.16. During this period, growth in these countries was much larger than average. Growth rates for thesecountries were about three times as fast as growth in the United States. However, most of this growth can be attributed to increases in the capital stocks in these countries, and such rapid rates of growth of capital cannot be sustained for long periods of time.Problems1. The amount of land increases, and, at first, the size of the population is unchanged. Therefore,consumption per capita increases. However, the increase in consumption per capita increases the population growth rate, see the figure below. In the steady state, neither *c nor *l are affected by the initial increase in land. This fact can be discerned by noting that there will be no changes in either of the panels of Figure 6.8 in the textbook.56 Williamson • Macroeconomics, Third Edition2. A reduction in the death rate increases the number of survivors from the current period who will stillbe living in the future. Therefore, such a technological change in public health shifts the function ()g cupward. In problem #1 there were no effects on the levels of land per capita and consumption per capita. In this case, the ()g c function in the bottom figure below shifts upward. Equilibriumconsumption per capita decreases. From the top figure below, we also see that the decrease inconsumption per capita requires a reduction in the equilibrium level of land per capita. The size of the population has increased, but the amount of available land is unchanged.Chapter 6 Economic Growth: Malthus and Solow 57 3. For the marginal product of capital to increase at every level of capital, the shift in the productionfunction is equivalent to an increase in total factor productivity.(a) The original and new production functions are depicted in the figures below.(b) Equilibrium in the Solow model is at the intersection of ()n d k+szf k with the line segment ().The old and new equilibria are depicted in the bottom panel of the figure above. The newequilibrium is at a higher level of capital per capita and a higher level of output per capita.(c) For a given savings rate, more effective capital implies more savings, and in the steady state thereis more capital and more output. However, if the increase in the marginal product of capital were local, in the neighborhood of the original equilibrium, there would be no equilibrium effects. A twisting of the production function around its initial point does not alter the intersection point.4. An increase in the depreciation rate acts in much the same way as an increase in the populationgrowth rate. More of current savings is required just to keep the amount of capital per capita constant.In equilibrium output per capita and capital per capita decrease.58 Williamson • Macroeconomics, Third Edition5. A destruction of capital.(a) The long-run equilibrium is not changed by an alteration of the initial conditions. If the economystarted in a steady state, the economy will return to the same steady state. If the economy wereinitially below the steady state, the approach to the steady state will be delayed by the loss ofcapital.(b) Initially, the growth rate of the capital stock will exceed the growth rate of the labor force. Thefaster growth rate in capital continues until the steady state is reached.(c) The rapid growth rates are consistent with the Solow model’s predictions about the likelyadjustment to a loss of capital.6. A reduction in total factor productivity reduces the marginal product of capital. The golden rule levelof capital per capita equates the marginal product of capital with .n d + Therefore, for given ,n d + the golden rule amount of capital per capita must decrease as in the figure below. Therefore the golden rule savings rate must decrease.7. Government spending in the Solow model.(a) By assumption, we know that T = G, and so we may write:()(1)(1)K's Y G d K sY gN d K =−+−=−+−Now divide by N and rearrange as:(1)()(1)k'n szf k sg d k +=−+−Divide by (1 + n ) to obtain:()(1)(1)(1)(1)szf k sg d k k'n n n −=−++++Chapter 6 Economic Growth: Malthus and Solow 59Setting k = k ′, we find that:**()().szf k sg n d k =++This equilibrium condition is depicted in the figure below.(b) The two steady states are also depicted in the figure above.(c) The effects of an increase in g are depicted in the bottom panel of the figure above. Capital percapita declines in the steady state. Steady-state growth rates of aggregate output, aggregate consumption, and investment are all unchanged. The reduction in capital per capita isaccomplished through a temporary reduction in the growth rate of capital.8. The golden rule quantity of capital per capita, *,k is such that *().K MP zf k n d ′==+ A decrease in the population growth rate, n , requires a decrease in the marginal product of capital. Therefore, thegolden rule quantity of capital per capita must increase. The golden rule savings rate may either increase or decrease.60 Williamson • Macroeconomics, Third Edition9. (a) First, we need to determine how bN evolves over time:(bN )′ = (1 + f )(1 + n ) bNThen we just need to redo the analysis of the competitive equilibrium and the steady state as inthe book, replacing every N by bN , every (1 + n ) by (1 + f )(1 + n ), and every n by f + n . The new steady-state per efficiency unit capital is then******()(1)(1)(1)(1)(1)szf k d k k f n f n −=+++++ All aggregate variables then grow at the rate of f + n , while per capita aggregates grow at therate f .(b) An increase in f increases the growth rate of per capita income by the same amount, as f is itsgrowth rate. This happens because the exogenous growth in b raises instant capital and income for everyone without a need to invest in capital.10. Production linear in capital:()()Y K z zf k f k k N N==⇒= (a) Recall Equation (20) from the text, and replace ()f k with k to obtain:+−=+((1))(1)sz d k'k n Also recall that 11 and .Y Y Y'zk k k'N z N z N'=⇒== Therefore: ((1))(1)Y'sz d Y N'n N+−=+ As long as((1))1,(1)sz d n +−>+ per capita income grows indefinitely. (b) The growth rate of income per capita is therefore: ((1))1(1)()(1)Y'Y sz d N'N g Y n Nsz n d n −+−==−+−+=+ Obviously, g is increasing in s .(c) This model allows for the possibility of an ever-increasing amount of capital per capita. In theSolow model, the fact that the marginal product of capital is declining in capital is the key impediment to continual increases in the amount of capital per capita.Chapter 6 Economic Growth: Malthus and Solow 6111. Solow residual calculations.(a) To calculate the Solow residuals, we apply the formula, 0.360.64ˆˆˆˆ/,zY K N = to the values in the provided table. Adding a new column for these values, we obtain:Year ˆY ˆK ˆN ˆz 1995 8031.7 25487.3 124.9 9.4781996 8328.9 26222.3 126.7 9.6401997 8703.5 27018.1 129.6 9.8231998 9066.9 27915.9 131.5 10.0191999 9470.3 28899.9 133.5 10.2362000 9817.0 29917.1 136.9 10.3122001 9890.7 30793.4 136.9 10.2822002 10048.8 31599.6 136.5 10.3692003 10301.0 32426.2 137.7 10.4722004 10703.5 33304.9 139.2 10.7032005 11048.6 34191.7 141.7 10.820(b) Next, we compute the percentage changes in each of the table entries. These values arepresented in the table below.Year ˆˆY Y Δ/ (%) ˆˆK K Δ/ (%) ˆˆN N Δ/ (%) ˆˆzz Δ/ (%) 1996 3.70 2.88 1.44 1.71 1997 4.50 3.03 2.29 1.901998 4.18 3.32 1.47 2.001999 4.45 3.52 1.52 2.172000 3.66 3.52 2.55 0.742001 0.75 2.93 0.00 −0.292002 1.60 2.62 −0.29 0.852003 2.51 2.62 0.88 0.992004 3.91 2.71 1.09 2.212005 3.22 2.66 1.80 1.0962 Williamson • Macroeconomics, Third EditionTo compare the contributions to growth, we need to compare the magnitudes,ˆˆˆˆ0.36(/),0.64(/),KKNN ΔΔ and ˆˆ/.z z Δ These values are presented in the table below.Year ˆˆ0.36(Δ/K K) (%) ˆˆ0.64(Δ/N N)(%) ˆˆz z Δ/ (%)1996 1.04 0.92 1.711997 1.09 1.46 1.901998 1.20 0.94 2.001999 1.27 0.97 2.172000 1.27 1.63 0.742001 1.05 0.00 −0.292002 0.94 −0.19 0.852003 0.94 0.56 0.992004 0.98 0.70 2.212005 0.96 1.15 1.09Most often, when output is growing, the biggest contribution to growth comes from increases intotal factor productivity. In 1991 and in 2001, both bad years for growth, total factor productivity decreased. In the other years, growth in total factor productivity is usually the largest contributor to growth, while increases in capital and labor equally share the role of the leading cause of growth in the other years. In the later years, capital growth has come to be relatively more important than in the early years.。
宏观经济学-课后思考题答案-史蒂芬威廉森004.pdf_英中
7.休闲代表所有用于非市场活动的时间。如果政府现在提供其中的一些，比如提供免费的儿童保育，家庭将会利用这样一个项目，从而为包括市场工作在内的其他活动留出更多的时间。具体来说，这意味着家庭偏好的改变。对于同样的消费，他们现在愿意多工作，或者换句话说，他们愿意放弃一些额外的休闲。下图中，新的无差异曲线标记为I2。它可以跨越I1的无差异曲线，因为我们在这里衡量的偏好已经发生了变化。家庭的平衡商品篮子现在从甲转移到乙。这导致休闲减少(从l 1到l 2)，工作时间增加，消费增加(从C1到C2)，这要归功于固定工资下更高的劳动收入。
2.U=al+bc
（a）为了指定一条无差异曲线，我们将效用常数保持在u。下一步以下列形式重新排成线性关系，斜率a/b代表边际替代率。根据是a/b>w还是a/b<w，主要有两种情况。左下图的顶部面板显示了a/b<w。在这种情况下，无差异曲线比预算线更平坦，消费者选择点A，在该点l = 0且C=wh+π-T。右图显示了a/b>w,在这种情况下，无差异曲线比预算线更陡，消费者选择B点，在该点l=h和C=π-T。在巧合的情况下，可达到的最高无差异曲线与无差异曲线一致，消费者对所有可能的休闲和工作时间漠不关心。
第三个特性是消费和休闲都是正常的商品。这一特性向我们保证，消费者收入的增加总是会促使个人消费更多的消费和休闲。
斯蒂芬D威廉森宏观经济学第三版第九章Stephen D. Williamson's Macroeconomics, Third Edition chapter9
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
9-2
Real Intertemporal Model
• Current and future periods. • Representative Consumer – consumption/savings decision • Representative Firm – hires labor and invests in current period, hires labor in future • Government – spends and taxes in present and future, and borrows on the credit market.
9-22
The Representative Firm’s Investment Decision
The firm invests to the point where the marginal benefit from investment equals the marginal cost.
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
9-26
Equation 9.16
Simplified optimal investment rule:
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
宏观经济学斯蒂芬威廉森chap09
宏观经济学斯蒂芬威廉森chap09Macroeconomics, 3e (Williamson)Chapter 9 A Real Intertemporal Model with Investment1) A consumer may increase her saving byA) w orking more hours and consuming more goods in the present period.B) w orking more hours and consuming fewer goods in the present period.C) w orking fewer hours and consuming more goods in the present period.D) w orking fewer hours and consuming fewer goods in the present period.Answer: BQuestion Status: P revious Edition2) T he condition, MRS l,C=w, describes the representative consumer'sA) i nvestment decision.B) c onsumption - savings decision.C) c urrent period work - leisure decision.D) f uture period work - leisure decision.Answer: CQuestion Status: P revious Edition3) T he condition, MRS l',C'= w', describes the representative consumer'sA) i nvestment decision.B) c onsumption - savings decision.C) c urrent period work - leisure decision.D) f uture period work - leisure decision.Answer: D4) T he condition, MRS C,C'= 1 +r, describes the representative consumer'sA) i nvestment decision.B) c onsumption - savings decision.C) c urrent period work - leisure decision.D) f uture period work - leisure decision.Answer: BQuestion Status: P revious Edition5) T he assumption that current-period labor supply is positively related to the current-periodreal wage is justified as long as theA) i ncome effect dominates the substitution effect in the short run.B) i ncome effect dominates the substitution effect in the long run.C) s ubstitution effect dominates the income effect in the short run.D) s ubstitution effect dominates the income effect in the long run.Answer: CQuestion Status: P revious Edition6) T he intertemporal substitution of leisure effect is used to justify the assumption that currentlabor supply increases when theA) c urrent real wage increases.B) c urrent real wage decreases.C) r eal interest rate increases.D) r eal interest rate decreases.Answer: C7) W hen drawn against the current wage, the current labor supply shifts to the right ifA) c urrent taxes increase.B) f uture taxes decrease.C) f irms make more profits.D) t otal factor productivity increases.Answer: AQuestion Status: N ew8) A n increase in lifetime wealth is likely toA) i ncrease current labor supply and increase current consumption demand.B) i ncrease current labor supply and decrease current consumption demand.C) d ecrease current labor supply and increase current consumption demand.D) d ecrease current labor supply and decrease current consumption demand.Answer: CQuestion Status: P revious Edition9) A ny increase in the present value of taxes for the consumer impliesA) a n increase in lifetime wealth and an increase in current labor supply.B) a n increase in lifetime wealth and a decrease in current labor supply.C) a decrease in lifetime wealth and an increase in current labor supply.D) a decrease in lifetime wealth and a decrease in current labor supply.Question Status: P revious Edition10) A ny increase in the present value of dividends for the consumer impliesA) a n increase in lifetime wealth and an increase in current labor supply.B) a n increase in lifetime wealth and a decrease in current labor supply.C) a decrease in lifetime wealth and an increase in current labor supply.D) a decrease in lifetime wealth and a decrease in current labor supply.Answer: BQuestion Status: N ew11) T he assumption that current-period consumption demand is positively related to the realinterest rate is justified as long as theA) i ncome effect dominates the substitution effect.B) s ubstitution effect dominates the income effect.C) r epresentative consumer is a borrower.D) r epresentative consumer is a lender.Answer: BQuestion Status: P revious Edition12) T he demand for current consumption, as plotted against current income, shifts to the rightdue to all of the following exceptA) a decrease in current taxes.B) a decrease in future taxes.C) a n increase in current income.D) a n increase in future income.Question Status: P revious Edition13) T he demand for current consumption, as plotted against the interest rate, shifts to the rightdue to all of the following exceptA) a decrease in current taxes.B) a increase in future taxes.C) a n increase in current income.D) a n increase in future income.Answer: BQuestion Status: N ew14) T he marginal propensity to consume out of incomeA) i s larger than one.B) i s equal to one.C) i s smaller than one.D) v aries around one.Answer: CQuestion Status: N ew15) T he marginal propensity to consume helps explaining which stylized fact?A) p rocyclicality of consumptionB) t he lag of consumptionC) t he low relative volatility of consumptionD) c ountercyclical pricesAnswer: CQuestion Status: N ew16) N ext period's capital is equal to current-period investmentA) p lus the amount of current capital left over after depreciation.B) m inus the amount of current capital left over after depreciation.C) p lus the amount of current period depreciation.D) m inus the amount of current period depreciation.Answer: AQuestion Status: P revious Edition17) W hen drawn against the current real wage, the labor demand curve isA) u pward sloping because the marginal product of labor rises with the quantity of laboremployed.B) u pward sloping because the marginal product of labor declines with the quantity oflabor employed.C) d ownward sloping because the marginal product of labor rises with the quantity oflabor employed.D) d ownward sloping because the marginal product of labor declines with the quantity oflabor employed.Answer: DQuestion Status: P revious Edition18) W hen drawn against the current real wage, the labor demand curve shift to the right ifA) t he interest rate increases.B) c urrent taxes increase.C) t otal factor productivity increases.D) f uture capital increases.Answer: CQuestion Status: N ew19) I n determining the benefit of additional investment to the representative firm, we considerthe marginal product ofA) c urrent capital.B) f uture capitalC) c urrent labor.D) f uture labor.Answer: BQuestion Status: N ew20) T he marginal cost of investment for the firm is equal toA) 1.B) -1.C) M P'K .D) -MP'K .Answer: AQuestion Status: P revious Edition21) T he marginal cost of investment for the firm is equal toA) 1.B) 0.C) t he depreciation rate.D) t he depreciation rate plus the interest rate.Answer: AQuestion Status: N ew22) T he marginal benefit from investment for a firm is equal to A) '1(1)K MP d r +++. B) '1(1)K MP d r ?++. C) '1(1)K MP d r +?+. D) '1(1)K MP d r ??+. Answer: CQuestion Status: P revious Edition23) W hen drawn against the real interest rate, the optimal investment schedule shifts to the rightifA) c urrent total factor productivity z increases.B) c urrent total factor productivity z decreases.C) f uture total factor productivity z' increases.D) f uture total factor productivity z' decreases.Answer: CQuestion Status: P revious Edition24) F irms discount future profits at the interest rate r becauseA) i t is the interest rate on their debt.B) i t is the same rate as for households.C) R icardian equivalence holds.D) i t has to equal the marginal productivity of capital in equilibrium.Answer: BQuestion Status: N ew25) W hen drawn against the real interest rate, the optimal investment schedule shifts to the rightif theA) c urrent capital stock K increases.B) c urrent capital stock K decreases.C) f uture capital stock K' increases.D) f uture capital stock K' increases.Answer: BQuestion Status: P revious Edition26) I nvestment will be more variable if the real interest rate isA) m ore variable and future total factor productivity is morevariable.B) m ore variable and future total factor productivity is less variable.C) l ess variable and future total factor productivity is more variable.D) l ess variable and future total factor productivity is less variable.Answer: AQuestion Status: P revious Edition27) I f the interest rate goes up, what happens to the investment demand curve?A) I t shifts to the right.B) I t shift to the left.C) I t stays put.D) W e cannot tell.Answer: CQuestion Status: N ew28) L abor demand depends on the interest rate becauseA) h ousehold savings depend on the interest rate.B) f irms discount future profits.C) o f Ricardian equivalence.D) L abor demand actually does not depend on the interest rate.Answer: DQuestion Status: N ew29) W hen drawn against the real interest rate, the output supply curve is upward slopingbecause labor supply isA) i ncreasing in the real interest rate and labor demand is independent of the real interestrate.B) d ecreasing in the real interest rate and labor demand is independent of the real interestrate.C) i ndependent of the real interest rate and labor demand is increasing in the real interestrate.D) i ndependent of the real interest rate and labor demand is decreasing in the real interestrate.Answer: AQuestion Status: P revious Edition30) O utput supply is increasing in the interest rate becauseA) l abor demand is increasing in the interest rate.B) l abor demand is decreasing in the interest rate.C) l abor supply is increasing in the interest rate.D) l abor supply is decreasing in the interest rate.Answer: CQuestion Status: N ew31) W hen drawn against the real interest rate, the output supply curve unambiguously shifts tothe right if either or both of the following occur.A) a n increase in current government spending and an increase in future governmentspendingB) a n increase in current government spending and a decrease in future governmentspendingC) a decrease in current government spending and an increase in future governmentspendingD) a decrease in current government spending and a decrease in future governmentspendingAnswer: AQuestion Status: P revious Edition32) W hen drawn against the real interest rate, the output supply curve unambiguously shifts tothe right ifA) c urrent capital decreases.B) c urrent total factor productivity decreases.C) f uture total factor productivity decreases.D) c urrent or future taxes increase.Answer: DQuestion Status: N ew33) W hen drawn against the real interest rate, output supply increases ifA) c urrent government expenses increase.B) f uture government expenses increase.C) c urrent total factor productivity increases.D) t he money supply increases.Answer: CQuestion Status: N ew34) W hen drawn against the real interest rate, output supply increases ifA) t he present value of taxes decreases.B) c urrent capital increases.C) t he interest rate decreases.D) f uture total productivity increases.Answer: BQuestion Status: N ew35) I n a model with money neutrality, how much should the money supply be increased toobtain a 1% increase in nominal output?A) -1%B) b etween 0 and 1%C) 1%D) I t cannot be done.Answer: CQuestion Status: N ew36) I n a model with money neutrality, how much should the money supply be increased toobtain a 1% increase in real output?A) -1%B) b etween 0 and 1%C) 1%D) I t cannot be done.Answer: DQuestion Status: N ew37) When drawn against current income, the slope of the Cd (r) + l d (r) + G curve is equal to themarginalA) p roduct of capital.B) p roduct of labor.C) p ropensity to consume.D) p ropensity to save.Answer: CQuestion Status: P revious Edition38) W hen drawn against the real interest rate, the output demand curve unambiguously shiftsto the right if either or both of the following occur.A) a n increase in current taxes and an increase in future taxesB) a n increase in current taxes and a decrease in future taxesC) a decrease in current taxes and an increase in future taxesD) a decrease in current taxes and a decrease in future taxesAnswer: DQuestion Status: P revious Edition39) W hen drawn against the real interest rate, output demand increases ifA) c urrent government expenses increase.B) f uture government expenses increase.C) c urrent taxes increase.D) f uture taxes increase.Answer: AQuestion Status: N ew40) W hen drawn against the real interest rate, the output demand curve unambiguously shiftsto the right ifA) c urrent capital decreases.B) c urrent total factor productivity decreases.C) f uture total factor productivity decreases.D) c urrent or future taxes increase.Answer: AQuestion Status: N ew41) W hich of these curves is directly affected by a change in current capital?A) o utput demandB) o utput supplyC) l abor supplyD) c onsumption demandAnswer: BQuestion Status: N ew42) W hen drawn against the real interest rate, the output demand curve shifts to the right whenA) c urrent total factor productivity z increases.B) c urrent total factor productivity z decreases.C) f uture total factor productivity z' increases.D) f uture total factor productivity z' decreases.Answer: CQuestion Status: P revious Edition43) A temporary increase in government spending that leads to only a small decline in lifetimewealth likely shifts the aggregate demand curve to theA) r ight by more than the rightward shift in aggregate supply.B) r ight by less than the rightward shift in aggregate supply.C) l eft by more than the leftward shift in aggregate supply.D) l eft by less than the leftward shift in aggregate supply.Answer: AQuestion Status: P revious Edition44) A change in current government expenses induces a direct shift in which curve?A) l abor supplyB) l abor demandC) a ggregate supplyD) a ggregate demandAnswer: DQuestion Status: N ew45) A ny increase in the present value of taxes impliesA) a n increase in lifetime wealth and an increase in the current labor supply.B) a n increase in lifetime wealth and a decrease in the current labor supply.C) a decrease in lifetime wealth and an increase in the current labor supply.D) a decrease in lifetime wealth and a decrease in the current labor supply.Answer: CQuestion Status: N ew46) I n response to a temporary increase in government spending, the representative consumerconsumesA) m ore and takes more leisure.B) m ore and takes less leisure.C) l ess and takes more leisure.D) l ess and takes less leisure.Answer: DQuestion Status: P revious Edition47) T he equilibrium effects of a temporary increase in government spending includeA) a n increase in the real wage and an increase in the real interest rate.B) a n increase in the real wage and a decrease in the real interest rate.C) a decrease in the real wage and an increase in the real interest rate.D) a decrease in the real wage and a decrease in the real interest rate.Answer: CQuestion Status: P revious Edition48) T he equilibrium effects of an anticipated increase infuture government spending includeA) a n increase in the real wage and an increase in the real interest rate.B) a n increase in the real wage and a decrease in the real interest rate.C) a decrease in the real wage and an increase in the real interest rate.D) a decrease in the real wage and a decrease in the real interest rate.Answer: DQuestion Status: P revious Edition49) I n response to a permanent increase in government spending, the permanent incomehypothesis would suggest that, to a first approximation, consumption demand shouldA) b e unaffected.B) f all by less than the increase in government spending.C) f all exactly as much as the increase in government spending.D) f all by more than the increase in government spending.Answer: CQuestion Status: P revious Edition50) A ccording to S. Rao Aiyagari, Lawrence Christiano and Martin Eichenbaum, outputA) i ncreases more with a temporary increase in government spending than with apermanent increase in government spending.B) i ncreases less with a temporary increase in government spending than with apermanent increase in government spending.C) d ecreases more with a temporary increase in government spending than with apermanent increase in government spending.D) d ecreases less with a temporary increase in government spending than with apermanent increase in government spending.Answer: BQuestion Status: P revious Edition51) A likely explanation for the extremely large reduction in investment spending during WorldWar II would beA) t he extremely large increase in output during the period.B) t he extremely large increase in real interest rates during the period.C) t hat consumption spending fell very little.D) t hat there was much government control over prices and the distribution of rawmaterials during the period.Answer: DQuestion Status: P revious Edition52) T he response of output following a natural disaster includesA) a n increase in aggregate demand and an increase in aggregate supply.B) a n increase in aggregate demand and a decrease in aggregate supply.C) a decrease in aggregate demand and an increase in aggregate supply.D) a decrease in aggregate demand and a decrease in aggregate supply.Answer: BQuestion Status: P revious Edition53) T he equilibrium effects of a temporary increase in total factor productivity includeA) a n increase in the real wage and an increase in the real interest rate.B) a n increase in the real wage and a decrease in the real interest rate.C) a decrease in the real wage and an increase in the real interest rate.D) a decrease in the real wage and a decrease in the real interest rate.Answer: BQuestion Status: P revious Edition54) H ow many of the following business cycle facts can be explained if the primary cause ofbusiness cycles is temporary changes in total factor productivity: procyclical consumption, procyclical investment, procyclical employment, and procyclical real wages?A) o neB) t woC) t hreeD) f ourAnswer: DQuestion Status: P revious Edition55) T he equilibrium effects of a prospective future increase in total factor productivity includeA) a n increase in the real wage and an increase in the real interest rate.B) a n increase in the real wage and a decrease in the realinterest rate.C) a decrease in the real wage and an increase in the real interest rate.D) a decrease in the real wage and a decrease in the real interest rate.Answer: CQuestion Status: P revious Edition56) I f future total factor productivity increasesA) l abor demand increases.B) g overnment expenses increase.C) c onsumption demand decreases.D) i nvestment demand increases.Answer: DQuestion Status: N ew57) I f consumption demand increases and the labor supply decreases, it must be thatA) t he real wage increases and the interest rate increases.B) t he real wage increases and the interest rate decreases.C) t he real wage decreases and the interest rate increases.D) t he real wage decreases and the interest rate decreases.Answer: BQuestion Status: N ew58) I f consumption demand increases and the labor supply decreases,A) o utput increases.B) o utput decreases.C) o utput does not change.D) o utput may change either way.Answer: DQuestion Status: N ew59) W hat could result in an increase of consumption demand and a decrease in the laborsupply?A) a drop in current taxesB) a n increase in future taxesC) a decrease in total factor productivityD) a n increase in government expensesAnswer: AQuestion Status: N ew60) I n the business cycle models we looked at so far, we assumed that prices (w and r) wereA) c ompletely flexible.B) s omewhat flexible.C) r igid.D) e xogenous.Answer: AQuestion Status: N ew61) I n general equilibriumA) s upply equals demand for all goods in all periods.B) s upply equals demand for most goods in all periods.C) s upply equals demand in present value, but not in all periods.D) p rices are exogenous.Answer: AQuestion Status: N ew。
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Figure 6.10 Adjustment to the Steady State in the Malthusian Model When z Increases
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
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Figure 6.7 The Per-Worker Production Function
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Figure 6.8 Determination of the Steady State in the Malthusian Model
6-4
Real Per Capita Income and the Investment Rate
Across countries, real per capita income and the investment rate are positively correlated.
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
• There is no tendency for rich countries to grow faster than poor countries, and vice-versa. • Rich countries are more alike in terms of rates of growth than are poor countries.
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
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An increase in z in the Malthusian model
• If z increases, this shifts up the per-worker production function. • In the long run, the population increases to the point where per capita consumption returns to its initial level. • There is no long-run change in living standards.
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
6-24
Figure 6.9 The Effect of an Increase in z in the Malthusian Model
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6-14
Equation 6.4: Equilibrium evolution of the population
This equation describes how the future population depends on current population.
Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
Chapter 6
Economic Growth: Malthus and Solow
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Chapter 6 Topics
• • • • Economic growth facts Malthusian model of economic growth Solow growth model Growth accounting
Population Control in the Malthusian Model
• Population control alters the relationship between population growth and per-capita consumption. • In the long run, per capita consumption increases, and living standards rise.
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Equation 6.8
Population growth is increasing in consumption per worker, c
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Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
6-11
Equation 6.1: Production Function
Output is produced from land and labor inputs.
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Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
6-3
Figure 6.1 Natural Log of Real PerCapita Income in the United States, 1869–2005
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Equation 6.6: The per-worker production function
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6-19
Equation 6.7: Equilibrium condition in per-worker form
Across countries, real per capita income and the population growth rate are negatively correlated.
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Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
6-2
U.S. Per Capita Income Growth
In the United States, growth in per capita income has not strayed far from 2% per year (excepting the Great Depression and World War II) since 1900.
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Figure 6.5 Population Growth Depends on Consumption per Worker in the Malthusian Model
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Equation 6.2: Evolution of the population
Population growth is higher the higher is percapita consumption.
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Copyright © 2008 Pearson Addison-Wesley. All rights reserved.
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Figure 6.11 Population Control in the Malthusian Model
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6-13
Equation 6.3: Equilibrium Condition
In equilibrium, consumption equals output produced.
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6-5
Figure 6.2 Real Income Per Capita vs. Investment Rate
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6-6
Real per capita income and the rate of population growth
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6-10
A Malthusian Model of Economic Growth