平狄克微观经济学课后习题答案(中文)
平狄克《微观经济学》课后答案 18
CHAPTER 18EXTERNALITIES AND PUBLIC GOODSThis chapter extends the discussion of market failure begun in Chapter 17. To avoid over-emphasis on definitions, stress the main theme of the chapter: the characteristics of some goods lead to situations where price is not equal to marginal cost. Rely on the discussion of market power (Chapter 10) as an example of market failure. Also, point out with each case that government intervention might not be required if property rights can be defined and transaction costs are small (Section 18.3). The first four sections present positive and negative externalities and solutions to market failure. The last two sections discuss public goods and public choice.The consumption of many goods involves the creation of externalities. Stress the divergence between social and private costs. Exercise (5) presents the classic beekeeper/apple-orchard problem, originally popularized in Meade, “External Economies and Diseconomies in a Competitive Situation,” Economic Journal (March 1952). Empirical research on this example has shown that beekeepers and orchard owners have solved many of their problems: see Cheung, “The Fable of the Bees: An Economic Investigation,” Journal of Law and Economics (April 1973).Solutions to the problems of externalities are presented in Sections 18.2 and 18.3. Section 18.2, in particular, discusses emission standards, fees, and transferable permits. Example 18.1 and Exercise (3) are simple applications of these concepts.One of the main themes of the law and economics literature since 1969 is the application of Coase’s insight on the assignment of property rights. The original article is clear and can be understood by students. Stress the problems posed by transactions costs. For a lively debate, ask students whether non-smokers should be granted the right to smokeless air in public places (see Exercise (4)). For an extended discussion of the Coase Theorem at the undergraduate level, see Polinsky, Chapters 3-6, An Introduction to Law & Economics (Little, Brown & Co., 1983).The section on common property resources emphasizes the distinction between private and social marginal costs. Example 18.5 calculates the social cost of unlimited access to common property, and the information provided is used in Exercise (7). Exercise (8) provides an extended example of managing common property.The last two sections focus on public goods and private choice. Point out the similarities and differences between public goods and other activities with externalities. Since students confuse nonrival and nonexclusive goods, create a table similar to the following and give examples to fill in the cells:The next stumbling block for students is achieving an understanding of why we add individual demand curves vertically rather than horizontally. Exercise (6) compares vertical and horizontal summation of individual demand.The presentation of public choice is a limited introduction to the subject, but you can easily expand on this material. A logical extension of this chapter is an introduction to cost-benefit analysis. For applications of this analysis, see Part III, “Empirical Analysis of Policies and Programs,” in Haveman and Margolis (eds.), Public Expenditure and Policy Analysis (Houghton Mifflin, 1983).1. Which of the following describes an externality and which does not? Explain the difference.a. A policy of restricted coffee exports in Brazil causes the U.S. price of coffee to rise,which in turn also causes the price of tea to increase.Externalities cause market inefficiencies by preventing prices from conveying accurateinformation. A policy of restricting coffee exports in Brazil causes the U.S. price ofcoffee to rise, because supply is reduced. As the price of coffee rises, consumers switchto tea, thereby increasing the demand for tea, and hence, increasing the price of tea.These are market effects, not externalities.b. An advertising blimp distracts a motorist who then hits a telephone pole.An advertising blimp is producing information by announcing the availability of somegood or service. However, its method of supplying this information can be distractingfor some consumers, especially those consumers who happen to be driving neartelephone poles. The blimp is creating a negative externality that influences thedrivers’ safety. Since the price charged by the advertising firm does not incorporate theexternality of distracting drivers, too much of this type of advertising is produced fromthe point of view of society as a whole.2. Compare and contrast the following three mechanisms for treating pollution externalities when the costs and benefits of abatement are uncertain: (a) an emissions fee, (b) an emissions standard, and (c) a system of transferable emissions permits.Since pollution is not reflected in the marginal cost of production, its emission createsan externality. Three policy tools can be used to reduce pollution: an emissions fee, anemissions standard, and a system of transferable permits. The choice between a feeand a standard will depend on the marginal cost and marginal benefit of reducingpollution. If small changes in abatement yield large benefits while adding little to cost,the cost of not reducing emissions is high. Thus, standards should be used. However, ifsmall changes in abatement yield little benefit while adding greatly to cost, the cost ofreducing emissions is high. Thus, fees should be used.A system of transferable emissions permits combines the features of fees and standardsto reduce pollution. Under this system, a standard is set and fees are used to transferpermits to the firm that values them the most (i.e., a firm with high abatement costs).However, the total number of permits can be incorrectly chosen. Too few permits willcreate excess demand, increasing price and inefficiently diverting resources to ownersof the permits. Typically, pollution control agencies implement one of threemechanisms, measure the results, reassess the success of their choice, then reset newlevels of fees or standards or select a new policy tool.3. When do externalities require government intervention, and when is such intervention unlikely to be necessary?Economic efficiency can be achieved without government intervention when theexternality affects a small number of people and when property rights are wellspecified. When the number of parties is small, the cost of negotiating an agreementamong the parties is small. Further, the amount of required information (i.e., the costsof and benefits to each party) is small. When property rights are not well specified,uncertainty regarding costs and benefits increases and efficient choices might not bemade. The costs of coming to an agreement, including the cost of delaying such anagreement, could be greater than the cost of government intervention, including theexpected cost of choosing the wrong policy instrument.4. An emissions fee is paid to the government, whereas an injurer who is sued and is held liable pays damages directly to the party harmed by an externality. What differences in the behavior of victims might you expect to arise under these two arrangements?When the price of an activity that generates an externality reflects social costs, anefficient level of the activity is maintained. The producer of the externality reduces (fornegative externalities) or increases (for positive externalities) activity away from(towards) efficient levels. If those who suffer from the externality are not compensated,they find that their marginal cost is higher (for negative externalities) or lower (forpositive externalities), in contrast to the situation in which they would be compensated.5. Why does free access to a common property resource generate an inefficient outcome?Free access to a resource means that the marginal cost to the user is less than the socialcost. The use of a common property resource by a person or firm excludes others fromusing it. For example, the use of water by one consumer restricts its use by another.Because private marginal cost is below social marginal cost, too much of the resource isconsumed by the individual user, creating an inefficient outcome.6. Public goods are both nonrival and nonexclusive. Explain each of these terms and state clearly how they differ from each other.A good is nonrival if, for any level of production, the marginal cost of providing the goodto an additional consumer is zero (although the production cost of an additional unitcould be greater than zero). A good is nonexclusive if it is impossible or very expensiveto exclude individuals from consuming it. Public goods are nonrival and nonexclusive.Commodities can be (1) exclusive and rival, (2) exclusive and nonrival, (3) nonexclusiveand rival, or (4) nonexclusive and nonrival. Most of the commodities discussed in thetext to this point have been of the first type. In this chapter, we focus on commodities ofthe last type.Nonrival refers to the production of a good or service for one more customer. It usuallyinvolves a production process with high fixed costs, such as the cost of building ahighway or lighthouse. (Remember that fixed cost depends on the period underconsideration: the cost of lighting the lamp at the lighthouse can vary over time, butdoes not vary with the number of consumers.) Nonexclusive refers to exchange, wherethe cost of charging consumers is prohibitive. Incurring the cost of identifyingconsumers and collecting from them would result in losses. Some economists focus onthe nonexclusion property of public goods because it is this characteristic that poses themost significant problems for efficient provision.7. Public television is funded in part by private donations, even though anyone with a television set can watch for free. Can you explain this phenomenon in light of the free rider problem?The free-rider problem refers to the difficulty of excluding persons from consuming anonexclusive commodity. Non-paying consumers can “free-ride” on commoditiesprovided by paying customers. Public television is funded in part by contributions.Some viewers contribute, but most watch without paying, hoping that someone else willpay so they will not. To combat this problem these stations (1) ask consumers to assesstheir true willingness to pay, then (2) ask consumers to contribute up to this amount,and (3) attempt to make everyone else feel guilty for free-riding.8. Explain why the median voter outcome need not be efficient when majority rule voting determines the level of public spending.The median voter is the citizen with the middle preference: half the voting population ismore strongly in favor of the issue and half is more strongly opposed to the issue.Under majority-rule voting, where each citizen’s vote is weighted equally, the preferredspending level on public-goods provision of the median voter will win an electionagainst any other alternative.However, majority rule is not necessarily efficient, because it weights each citizen’spreferences equally. For an efficient outcome, we would need a system that measuresand aggregates the willingness to pay of those citizens consuming the public good.Majority rule is not this system. However, as we have seen in previous chapters,majority rule is equitable in the sense that all citizens are treated equally. Thus, weagain find a trade-off between equity and efficiency.1. A number of firms located in the western portion of a town after single-family residences took up the eastern portion. Each firm produces the same product and, in the process, emits noxious fumes that adversely affect the residents of the community.a. Why is there an externality created by the firms?Noxious fumes created by firms enter the utility function of residents. We can assumethat the fumes decrease the utility of the residents (i.e., they are a negative externality)and lower property values.b. Do you think that private bargaining can resolve the problem with the externality?Explain.If the residents anticipated the location of the firms, housing prices should reflect thedisutility of the fumes; the externality would have been internalized by the housingmarket in housing prices. If the noxious fumes were not anticipated, privatebargaining could resolve the problem of the externality only if there are a relativelysmall number of parties (both firms and families) and property rights are well specified.Private bargaining would rely on each family’s willingness to pay for air quality, buttruthful revelation might not be possible. All this will be complicated by theadaptability of the production technology known to the firms and the employmentrelations between the firms and families. It is unlikely that private bargaining willresolve the problem.c. How might the community determine the efficient level of air quality?The community could determine the economically efficient level of air quality byaggregating the families’ willingne ss to pay and equating it with the marginal cost ofpollution reduction. Both steps involve the acquisition of truthful information.2. A computer programmer lobbies against copyrighting software. He argues that everyone should benefit from innovative programs written for personal computers and that exposure to a wide variety of computer programs will inspire young programmers to create even more innovative programs. Considering the marginal social benefits possibly gained by his proposal, do you agree with the programmer’s position?Computer software as information is a classic example of a public good. Since it can becostlessly copied, the marginal cost of providing software to an additional user is nearzero. Therefore, software is nonrival. (The fixed costs of creating software are high, butthe variable costs are low.) Furthermore, it is expensive to exclude consumers fromcopying and using software because copy protection schemes are available only at highcost or high inconvenience to users. Therefore, software is also nonexclusive. As bothnonrival and nonexclusive, computer software suffers the problems of public goodsprovision: the presence of free-riders makes it difficult or impossible for markets toprovide the efficient level of software. Rather than regulating this market directly, thelegal system guarantees property rights to the creators of software. If copyrightprotection were not enforced, it is likely that the software market would collapse.Therefore, we do not agree with the computer programmer.3. Four firms located at different points on a river dump various quantities of effluent into it. The effluent adversely affects the quality of swimming for homeowners who live downstream. These people can build swimming pools to avoid swimming in the river, and firms can purchase filters that eliminate harmful chemicals in the material that is dumped in the river. As a policy advisor for a regional planning organization, how would you compare and contrast the following options for dealing with the harmful effect of the effluent:a. An equal-rate effluent fee on firms located on the river.First, one needs to know the value to homeowners of swimming in the river. Thisinformation can be difficult to obtain, because homeowners will have an incentive tooverstate this value. As an upper boundary, if there are no considerations other thanswimming, one could use the cost of building swimming pools, either a pool for eachhomeowner or a public pool for all homeowners. Next, one needs to know the marginalcost of abatement. If the abatement technology is well understood, this informationshould be readily obtainable. If the abatement technology is not understood, anestimate based on the firms’ knowledge must be used.The choice of a policy tool will depend on the marginal benefits and costs of abatement.If firms are charged an equal-rate effluent fee, the firms will reduce effluents to thepoint where the marginal cost of abatement is equal to the fee. If this reduction is nothigh enough to permit swimming, the fee could be increased. Alternatively, revenuefrom the fees could be to provide swimming facilities, reducing the need for effluentreduction.b. An equal standard per firm on the level of effluent each firm can dump.Standards will be efficient only if the policy maker has complete information regardingthe marginal costs and benefits of abatement. Moreover, the standard will notencourage firms to reduce effluents further when new filtering technologies becomeavailable.c. A transferable effluent permit system, in which the aggregate level of effluent isfixed and all firms receive identical permits.A transferable effluent permit system requires the policy maker to determine theefficient effluent standard. Once the permits are distributed and a market develops,firms with a higher cost of abatement will purchase permits from firms with lowerabatement costs. However, unless permits are sold initially, rather than merelydistributed, no revenue will be generated for the regional organization.4. Recent social trends point to growing intolerance of smoking in public areas. Many people point out the negative effects of “second hand” smoke. If you are a smoker and you wish to continue smoking despite tougher anti smoking laws, describe the effect of the following legislative proposals on your behavior. As a result of these programs, do you, the individual smoker, benefit? Does society benefit as a whole?Since smoking in public areas is similar to polluting the air, the programs proposedhere are similar to those examined for air pollution. A bill to lower tar and nicotinelevels is similar to an emissions standard, and a tax on cigarettes is similar to anemissions fee. Requiring a smoking permit is similar to a system of emissions permits,assuming that the permits would not be transferable. The individual smoker in all ofthese programs is being forced to internalize the externality of “second-hand” smokeand will be worse off. Society will be better off if the benefits of a particular proposaloutweigh the cost of implementing that proposal. Unfortunately, the benefits ofreducing second-hand smoke are uncertain, and assessing those benefits is costly.a. A bill is proposed that would lower tar and nicotine levels in all cigarettes.The smoker will most likely try to maintain a constant level of consumption of nicotine,and will increase his or her consumption of cigarettes. Society may not benefit fromthis plan if the total amount of tar and nicotine released into the air is the same.b. A tax is levied on each pack of cigarettes sold.Smokers might turn to cigars, pipes, or might start rolling their own cigarettes. Theextent of the effect of a tax on cigarette consumption depends on the elasticity ofdemand for cigarettes. Again, it is questionable whether society will benefit.c. Smokers would be required to carry smoking permits at all times. These permitswould be sold by the government.Smoking permits would effectively transfer property rights to clean air from smokers tonon-smokers. The main obstacle to society benefiting from such a proposal would bethe high cost of enforcing a smoking permits system.5. A beekeeper lives adjacent to an apple orchard. The orchard owner benefits from thebees because each hive pollinates about one acre of apple trees. The orchard owner pays nothing for this service, however, because the bees come to the orchard without his having to do anything. There are not enough bees to pollinate the entire orchard, and the orchard owner must complete the pollination by artificial means, at a cost of $10 per acre of trees.Beekeeping has a marginal cost of MC = 10 + 2Q, where Q is the number of beehives.Each hive yields $20 worth of honey.a. How many beehives will the beekeeper maintain?The beekeeper maintains the number of hives that maximizes profits, when marginalrevenue is equal to marginal cost. With a constant marginal revenue of $20 (there is noinformation that would lead us to believe that the beekeeper has any market power)and a marginal cost of 10 + 2Q:20 = 10 + 2Q, or Q = 5.b. Is this the economically efficient number of hives?If there are too few bees to pollinate the orchard, the farmer must pay $10 per acre forartificial pollination. Thus, the farmer would be willing to pay up to $10 to thebeekeeper to maintain each additional hive. So, the marginal social benefit, MSB, ofeach additional hive is $30, which is greater than the marginal private benefit of $20.Assuming that the private marginal cost is equal to the social marginal cost, we setMSB = MC to determine the efficient number of hives:30 = 10 + 2Q, or Q = 10.Therefore, the beekeeper’s private choice of Q = 5 is not the socially efficient number ofhives.c. What changes would lead to the more efficient operation?The most radical change that would lead to more efficient operations would be themerger of the farmer’s business with the beekeeper’s business. This merger wouldinternalize the positive externality of bee pollination. Short of a merger, the farmerand beekeeper should enter into a contract for pollination services.7. Reconsider the common resource problem as given by Example 18.5. Suppose that crawfish popularity continues to increase, and that the demand curve shifts from C = 0.401 - 0.0064F to C = 0.50 - 0.0064F. How does this shift in demand affect the actual crawfish catch, the efficient catch, and the social cost of common access? (Hint: Use the marginal social cost and private cost curves given in the example.)The relevant information is now the following:Demand: C = 0.50 - 0.0064FMSC: C = -5.645 + 0.6509F.With an increase in demand, the demand curve for crawfish shifts upward, intersectingthe price axis at $0.50. The private cost curve has a positive slope, so additional effortmust be made to increase the catch. Since the social cost curve has a positive slope, thesocially efficient catch also increases. We may determine the socially efficient catch bysolving the following two equations simultaneously:0.50 - 0.0064F = -5.645 + 0.6509F, or F* = 9.35.To determine the price that consumers are willing to pay for this quantity, substituteF* into the equation for marginal social cost and solve for C:C = -5.645 + (0.6509)(9.35), or C = $0.44.Next, find the actual level of production by solving these equations simultaneously:Demand: C = 0.50 - 0.0064FMPC: C = -0.357 + 0.0573F0.50 - 0.0064F = -0.357 + 0.0573F, or F** = 13.45.To determine the price that consumers are willing to pay for this quantity, substituteF** into the equation for marginal private cost and solve for C:C = -0.357 + (0.0573)(13.45), or C = $0.41.Notice that the marginal social cost of producing 13.45 units isMSC = -5.645 +(0.6509)(13.45) = $3.11.With the increase in demand, the social cost is the area of a triangle with a base of 4.1million pounds (13.45 - 9.35) and a height of $2.70 ($3.11 - 0.41), or $5,535,000 morethan the social cost of the original demand.8. The Georges Bank, a highly productive fishing area off New England, can be divided into two zones in terms of fish population. Zone 1 has the higher population per square mile but is subject to severe diminishing returns to fishing effort. The daily fish catch (in tons) in Zone 1 isF 1 = 200(X1) - 2(X1) 2where X1is the number of boats fishing there. Zone 2 has fewer fish per mile but is larger, and diminishing returns are less of a problem. Its daily fish catch isF 2 = 100(X2) - (X2) 2where X2is the number of boats fishing in Zone 2. The marginal fish catch MFC in each zone can be represented asMFC1 = 200 - 4(X1) MFC2= 100 - 2(X2).There are 100 boats now licensed by the U.S. government to fish in these two zones. The fish are sold at $100 per ton. The total cost (capital and operating) per boat is constant at $1,000 per day. Answer the following questions about this situation.a. If the boats are allowed to fish where they want, with no government restriction,how many will fish in each zone? What will be the gross value of the catch?Without restrictions, the boats will divide themselves so that the average catch (AF 1and AF 2) for each boat is equal in each zone. (If the average catch in one zone is greaterthan in the other, boats will leave the zone with the lower catch for the zone with thehigher catch.) We solve the following set of equations:AF 1 = AF 2 and X 1 + X 2 = 100 where 11121120022002AF X X X X =-=- and 222222100100AF X X X X =-=-. Therefore, AF 1 = AF 2 implies200 - 2X 1 = 100 - X 2,200 - 2(100 - X 2) = 100 - X 2, or X 21003= and 320031001001=⎪⎭⎫ ⎝⎛-=X . Find the gross catch by substituting the value of X 1 and X 2 into the catch equations:()(),,,,F 444488983331332002320020021=-=⎪⎭⎫ ⎝⎛-⎪⎭⎫ ⎝⎛= and ().,,,F 2222111133333100310010022=-=⎪⎭⎫ ⎝⎛-⎪⎭⎫ ⎝⎛= The total catch is F 1 + F 2 = 6,666. At the price of $100 per ton, the value of the catch is$666,600. The average catch for each of the 100 boats in the fishing fleet is 66.66 tons.To determine the profit per boat, subtract total cost from total revenue:π = (100)(66.66) - 1,000, or π = $5,666.Total profit for the fleet is $566,000.b. If the U.S. government can restrict the boats, how many should be allocated to eachzone? What will the gross value of the catch be? Assume the total number of boats remains at 100.Assume that the government wishes to maximize the net social value of the fish catch,i.e., the difference between the total social benefit and the total social cost. Thegovernment equates the marginal fish catch in both zones, subject to the restrictionthat the number of boats equals 100:MFC 1 = MFC 2 and X 1 + X 2 = 100,MFC 1 = 200 - 4X 1 and MFC 2 = 100 - 2X 2.Setting MFC 1 = MFC 2 implies:200 - 4X 1 = 100 - 2X 2, or 200 - 4(100 - X 2) = 100 - 2X 2, or X 2 = 50 andX 1 = 100 - 50 = 50.Find the gross catch by substituting X 1 and X 2 into the catch equations:F 1 = (200)(50) - (2)(502) = 10,000 - 5,000 = 5,000 andChapter 18: Externalities and Public Goods242 F 2 = (100)(50) - 502 = 5,000 - 2,500 = 2,500.The total catch is equal to F 1 + F 2 = 7,500. At the market price of $100 per ton, thevalue of the catch is $750,000. Total profit is $650,000. Notice that the profits are notevenly divided between boats in the two zones. The average catch in Zone A is 100 tonsper boat, while the average catch in Zone B is 50 tons per boat. Therefore, fishing inZone A yields a higher profit for the individual owner of the boat.c. If additional fishermen want to buy boats and join the fishing fleet, should agovernment wishing to maximize the net value of the fish catch grant them licenses to do so? Why or why not?To answer this question, first determine the profit-maximizing number of boats in eachzone. Profits in Zone A areππA A X X X X X =--=-1002002100019000200112112b g e j,,, or . To determine the change in profit with a change in X 1 take the first derivative of theprofit function with respect to X 1:d dX X A π1119000400=-,. To determine the profit-maximizing level of output, setd dX A π1equal to zero and solve for X 1:19,000 - 400X 1 = 0, or X 1 = 47.5.Substituting X 1 into the profit equation for Zone A gives: ()()()()()()()()250,451$5.47000,15.4725.472001002=--=A π.For Zone B follow a similar procedure. Profits in Zone B areππB B X X X X X =--=-100100100090002002222222b g e j,,, or . Taking the derivative of the profit function with respect to X 2 givesd X B π229000200=-,. Setting d B π2equal to zero to find the profit-maximizing level of output gives 9,000 - 200X 2 = 0, or X 2 = 45.Substituting X 2 into the profit equation for Zone B gives:πB = (100)((100)(45) - 452) - (1,000)(45) = $202,500.Total profit from both zones is $653,750, with 47.5 boats in Zone A and 45 boats in ZoneB. Because each additional boat above 92.5 decreases total profit, the governmentshould not grant any more licenses.。
平狄克第八版课后答案
平狄克第八版课后答案【篇一:平狄克微观经济学课后习题答案-第7-8 章】> 1. 显性成本2. 她自己做其他事时会得到的最高收入3. 多用资本,少用工人4. 完全竞争价格给定, 即斜率不变5. 不意味6. 意味着递增7. avcac mc 递增mc=avc 最低点mc=ac 最低点1.1 形9 . 长期扩展线为把等产量线簇上斜率相同点连起来,此时它改变了斜率10 .规模经济基础是内在经济,针对一种产品范围经济基础是同时生产高度相关的产品.练习题1.avc=1000 ac=1000+1000/q非常大,最后为10002. 不对,除非工人只可以在这里找到工作3. 见书后4. 见书后5. 见书后6. 每个均衡点斜率更小7. 不同意,应按不同时段定价,如不可,则同意8. 见书后9.tc=120000+3000(q/40)+2000ac=75+122000/qmc=75ac 随q 减小2 个劳动组,1600 元1/4, 更大的生产能力11.190 万元53 元53 元19 元第七章附录练习题1 、我们考查规模报酬时可由f( ak,al)与af( k,l)之间的关系判断当f( ak,al) af( k,l),表明是规模报酬递增;当f( ak,al) =af( k,l),表明是规模报酬不变;当f( ak,al) af( k,l),表明是规模报酬递减;( a)规模报酬递增;( b)规模报酬不变;( c)规模报酬递增。
2 、根据已知条件,资本价格r=30 ,设劳动价格为w,则成本函数c=30k+ wl联立(1) ,(2),(3)可得k=(w/3) 1/2 ,l=(300/w) 1/2 ,此时成本最小,代入成本函数c=30k+ wl ,得c=2 ( 300w ) 1/2联立(1) ,(2),(3)可得k/l=3/4 ,此时成本最小,即生产既定产出的成本最小化的资本和劳动的组合为资本/劳动=3/4。
4、( a)已知q=10k0.8(l-40)0.2 ,得mpl=2(k/ (l-40))0.8 , mpk=8( (l-40) / k)0.2 ,在最小成本点有:mpl/ mpk=w/r即2(k/ (l-40))0.8/8( (l-40) / k)0.2=w/r ,k/( l-40) =4 w/r ,l-40=kr/4w ,0.80.20.2q=10k(l-40)=10 k ( r/4w),最小需求为:k=q/10(r/4w)0.2 ,l=40+ q (r/4w)0.8/10总成本函数为:tc=10q+kr+lw=10q+q/10((4w)0.2r0.8+(r/4)0.8w0.2)+40w( b)当r=64 ,w=32 时tc=10q+ (2*20.2+0.50.8)32 q/10+1280tc=1280+10q+91.84 q/10=1280+19.184q该技术呈现规模递减。
平狄克《微观经济学》(第8版)笔记和课后习题详解
第1篇导论:市场和价格第1章绪论1.1复习笔记1.微观经济学的主题(1)微观经济学的研究对象微观经济学研究的是个体经济单位(如消费者、工人、投资者、土地所有者和企业)的行为,也研究构成市场与行业的消费者和厂商的相互影响。
微观经济学的核心内容是论证亚当·斯密的“看不见的手”原理。
(2)经济模型经济模型是现代经济理论的一种主要分析方法,也称为经济数学模型,指用数学形式所表述的经济过程或经济理论结构。
现实世界的情况是由各种主要变量和次要变量构成的,因而非常复杂,只有把次要因素排除在外,才能对经济运行进行严格的分析。
运用经济模型,事先做出某些假设,可以排除掉许多次要因素,从而建立起一定的模型,然后通过运用这一模型,可以对错综复杂的现实世界做出简单的描述。
(3)经济理论的局限性在经济学、物理学或者其他学科中,没有一个理论是绝对正确的。
理论的有用性和合理性取决于它是否对其试图解释和预测的一系列现象成功地做出了解释和预测。
比如说,厂商并不总是追求其利润的最大化的,因此,厂商理论只在解释厂商某些行为(如资本投资决策的时机)时才获得了有限的成功。
尽管如此,这一理论确实解释了有关厂商和行业的行为、成长和演变方面的大量现象,所以它已经成为决策者手中一个重要的工具。
2.实证分析和规范分析(1)微观经济学的分析方法微观经济学既研究实证问题,也研究规范问题。
实证问题主要是解释和预测,规范问题则研究“应该如何”。
实证分析和规范分析都是重要的经济学分析方法。
(2)实证分析和规范分析的含义实证分析是进行经济分析的一种重要方法,特点是它对有关命题的逻辑分析,旨在理解经济过程实际是什么、将会是什么、为什么,而不涉及对结果好坏和是否公平的评价,其中不包含任何价值判断。
实证分析既有定性分析,也有定量分析。
规范分析也是经济学分析经济问题的一种方法,它以一定的价值判断作为出发点,提出行为的标准,并研究如何才能符合这些标准。
它力求说明“应该是什么”的问题,或者说,它回答这样的问题:为什么要做出这种选择,而不做出另一种选择?(3)实证分析和规范分析的关系实证分析和规范分析既有联系又有区别。
平狄克《微观经济学》(第9版)笔记和课后习题详解
平狄克《微观经济学》(第9版)笔记和课后习题详解
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第1篇导论:市场与价格
第1章绪论
1.1复习笔记
【知识框架】
【考点难点归纳】
考点一:微观经济学的主题(见表1-1)★
表1-1微观经济学的主题
考点二:微观经济学的分析方法——实证分析和规范分析(见表1-2)★★
表1-2微观经济学的分析方法——实证分析和规范分析
考点三:市场★
市场是指买者和卖者的集合,以及由此确定的潜在的买卖。
微观经济学中的市场不仅有买方和卖方都不会影响市场的竞争性市场,还有卖方影响市场的非竞争市场,如寡头市场、垄断竞争市场等。
市场是有范围的,不仅要考虑地理边界,还要考虑包含产品范围的大小。
如住房市场是高度当地化的,而黄金市场却是世界性的。
市场的价格是在买卖双方互动的基础上形成的。
一般而言,微观经济学考察市场均衡的价格,即一个市场上的供给等于需求时的价格。
考点四:名义价格与实际价格★★
1名义价格与实际价格的含义
名义价格是指以某些货币表示的,未经过通货膨胀的调整的价格。
实际价格则是指名义价格剔除通货膨胀因素之后的价格。
2名义价格与实际价格的关系
名义价格与实际价格的关系需要引入消费价格指数(CPI)。
居民消费价格指数是一个反映居民家庭一般所购买的消费品和服务项目价格水平变动情况的宏观经济指标,它是衡量通货膨胀的主要指标之一。
某年商品的实际价格与名义价格之间的关系为:
某年商品的实际价格=基准年消费物价指数/计算年消费物价指数×计算年的名义价格。
平狄克微观经济学第九本课后习题答案笔记
平狄克微观经济学第九版课后习题答案与笔记内容简介本书遵循平狄克《微观经济学》(第9版)教材的章⽬目编排,共分4篇19章,每章由三部分组成:第⼀一部分为复习笔记,总结本章的重难点内容;第⼆二部分为课(章)后复习题详解,对第9版的所有课(章)后复习题都进⾏行行了了详细的分析和解答;第三部分为课(章)后练习题详解,对第9版的所有课(章)后练习题都进⾏行行了了详细的分析和解答。
作为该教材的学习辅导书,本书具有以下⼏几个⽅方⾯面的特点:(1)整理理名校笔记,浓缩内容精华。
每章的复习笔记以平狄克所著的《微观经济学》(第9版)为主,并结合国内外其他微观经济学经典教材对各章的重难点进⾏行行了了整理理,因此,本书的内容⼏几乎浓缩了了经典教材的知识精华。
(2)解析课后习题,提供详尽答案。
本书参考⼤大量量经济学相关资料料对平狄克所著的《微观经济学》(第9版)的课(章)后习题进⾏行行了了详细的分析和解答,并对相关重要知识点进⾏行行了了延伸和归纳。
(3)补充相关要点,强化专业知识。
⼀一般来说,国外英⽂文教材的中译本不不太符合中国学⽣生的思维习惯,有些语⾔言的表述不不清或条理理性不不强⽽而给学习带来了了不不便便,因此,对每章复习笔记的⼀一些重要知识点和⼀一些习题的解答,我们在不不违背原书原意的基础上结合其他相关经典教材进⾏行行了了必要的整理理和分析。
⽬目录第1篇 导论:市场与价格 第1章 绪 论 1.1 复习笔记 1.2 课后复习题详解 1.3 课后练习题详解 第2章 供给与需求的基本原理 2.1 复习笔记 2.2 课后复习题详解 2.3 课后练习题详解第2篇 ⽣产者、消费者与竞争性市场 第3章 消费者⾏为 3.1 复习笔记 3.2 课后复习题详解 3.3 课后练习题详解 第4章 个⼈需求与市场需求 4.1 复习笔记 4.2 课后复习题详解 4.3 课后练习题详解 第4章附录 需求理论:⼀种数学的处理⽅法 第5章 不确定性与消费者⾏为 5.1 复习笔记 5.2 课后复习题详解 5.3 课后练习题详解 第6章 ⽣ 产 6.1 复习笔记 6.2 课后复习题详解 6.3 课后练习题详解 第7章 ⽣产成本 7.1 复习笔记 7.2 课后复习题详解 7.3 课后练习题详解 第7章附录 ⽣产与成本理论:⼀种数学的处理⽅法 第8章 利润最⼤化与竞争性供给 8.1 复习笔记 8.2 课后复习题详解 第9章 竞争性市场分析 9.1 复习笔记 9.2 课后复习题详解 9.3 课后练习题详解第3篇 市场结构与竞争策略 第10章 市场势⼒:垄断与买⽅垄断 10.1 复习笔记 10.2 课后复习题详解 10.3 课后练习题详解 第11章 有市场势⼒的定价 11.1 复习笔记 11.2 课后复习题详解 11.3 课后练习题详解 第11章附录 纵向联合⼚商 第12章 垄断竞争与寡头垄断 12.1 复习笔记 12.2 课后复习题详解 12.3 课后练习题详解 第13章 博弈论与竞争策略 13.1 复习笔记 13.2 课后复习题详解 13.3 课后练习题详解 第14章 投⼊要素市场 14.1 复习笔记 14.2 课后复习题详解 14.3 课后练习题详解 第15章 投资、时间与资本市场 15.1 复习笔记 15.2 课后复习题详解第4篇 信息、市场失灵与政府的⾓⾊ 第16章 ⼀般均衡与经济效率 16.1 复习笔记 16.2 课后复习题详解 16.3 课后练习题详解 第17章 信息不对称的市场 17.1 复习笔记 17.2 课后复习题详解 17.3 课后练习题详解 第18章 外部性与公共物品 18.1 复习笔记 18.2 课后复习题详解 18.3 课后练习题详解 第19章 ⾏为经济学 19.1 复习笔记 19.2 课后复习题详解 19.3 课后练习题详解附录 指定平狄克《微观经济学》教材为考研参考书⽬目的院校列列表1.2. 课后习题详解1 ⼈人们常说,⼀一个好的理理论是可以⽤用实证的、数据导向的研究来加以证伪的。
平狄克《微观经济学》(第8版)笔记和课后习题详解复习答案
平狄克《微观经济学》(第8版)笔记和课后习题详解完整版>精研学习䋞>无偿试用20%资料全国547所院校视频及题库全收集考研全套>视频资料>课后答案>往年真题>职称考试第1篇导论:市场和价格第1章绪论1.1复习笔记1.2课后复习题详解1.3课后练习题详解第2章供给和需求的基本原理2.1复习笔记2.2课后复习题详解2.3课后练习题详解第2篇生产者、消费者与竞争性市场第3章消费者行为3.1复习笔记3.2课后复习题详解3.3课后练习题详解第4章个人需求和市场需求4.1复习笔记4.2课后复习题详解4.3课后练习题详解第4章附录需求理论——一种数学的处理方法第5章不确定性与消费者行为5.1复习笔记5.2课后复习题详解5.3课后练习题详解第6章生产6.1复习笔记6.2课后复习题详解6.3课后练习题详解第7章生产成本7.1复习笔记7.2课后复习题详解7.3课后练习题详解第7章附录生产与成本理论——一种数学的处理方法第8章利润最大化与竞争性供给8.1复习笔记8.3课后练习题详解第9章竞争性市场分析9.1复习笔记9.2课后复习题详解9.3课后练习题详解第3篇市场结构与竞争策略第10章市场势力:垄断和买方垄断10.1复习笔记10.2课后复习题详解10.3课后练习题详解第11章有市场势力的定价11.1复习笔记11.2课后复习题详解11.3课后练习题详解第11章附录纵向联合厂商第12章垄断竞争和寡头垄断12.1复习笔记12.2课后复习题详解12.3课后练习题详解第13章博弈论与竞争策略13.1复习笔记13.2课后复习题详解13.3课后练习题详解第14章投入要素市场14.1复习笔记14.2课后复习题详解14.3课后练习题详解第15章投资、时间与资本市场15.1复习笔记15.2课后复习题详解15.3课后练习题详解第4篇信息、市场失灵与政府的角色第16章一般均衡与经济效率16.1复习笔记16.2课后复习题详解16.3课后练习题详解第17章信息不对称的市场17.1复习笔记17.2课后复习题详解17.3课后练习题详解第18章外部性和公共物品18.1复习笔记18.2课后复习题详解附录指定平狄克《微观经济学》教材为考研参考书目的院校列表。
平狄克《微观经济学》第七版·课后习题答案中文word资料68页
第一章复习题1.市场是通过相互作用决定一种或一系列产品价格的买卖双方的集合,因此可以把市场看作决定价格的场所。
行业是出售相同的或紧密相关的产品的厂商的集合,一个市场可以包括许多行业。
2.评价一个理论有两个步骤:首先,需要检验这个理论假设的合理性;第二,把该理论的预测和事实相比较以此来验证它。
如果一个理论无法被检验的话,它将不会被接受。
因此,它对我们理解现实情况没有任何帮助。
3.实证分析解释“是什么”的问题,而规范分析解释的是“应该是什么”的问题。
对供给的限制将改变市场的均衡。
A中包括两种分析,批评这是一种“失败的政策”——是规范分析,批评其破坏了市场的竞争性——是实证分析。
B向我们说明在燃油的配给制下总社会福利的被损坏——是实证分析。
4.由于两个市场在空间上是分离的,商品在两地间的运输是套利实现的条件。
如果运输成本为零,则可以在Oklahoma购买汽油,到New Jersey出售,赚取差价;如果这个差价无法弥补运输成本则不存在套利机会。
5.商品和服务的数量与价格由供求关系决定。
鸡蛋的实际价格从1970年至1985年的下降,一方面是由于人们健康意识的提高而导致鸡蛋需求的减少,同时也因为生产成本的降低。
在这两种因素下,鸡蛋的价格下降了。
大学教育的实际价格的升高,是由于越来越多的人倾向于获得大学教育而导致需求提高,同时教育的成本也在升高。
在这两方面因素作用下,大学教育费用提高了。
6.日圆相对美圆来说,价值升高,升值前相比,兑换同样数量的日圆需要付出更多的美圆。
由汇率的变化引起购买力的变化,在日本市场出售的美国汽车,由于美圆贬值日圆升值,持有日圆的消费者将较以前支付较底的价格;而在美国市场出售的日本汽车,由于日圆升值美圆贬值,持有美圆的消费者将面对较以前提高的价格。
第二章复习题1.假设供给曲线固定,炎热天气通常会引起需求曲线右移,在当前价格上造成短期需求过剩。
消费者为获得冰激凌,愿意为每一单位冰激凌出价更高。
平狄克微观经济学课后习题答案-第7-8章
第七章复习题1.显性成本2.她自己做其他事时会得到的最高收入3.多用资本,少用工人4.完全竞争价格给定,即斜率不变5.不意味6.意味着递增7.AVC<AC MC递增 MC=AVC最低点 MC=AC最低点8.L形9.长期扩展线为把等产量线簇上斜率相同点连起来,此时它改变了斜率10.规模经济基础是内在经济,针对一种产品范围经济基础是同时生产高度相关的产品.练习题1.AVC=1000 AC=1000+1000/Q非常大,最后为10002.不对,除非工人只可以在这里找到工作3.见书后4.见书后5.见书后6.每个均衡点斜率更小7不同意,应按不同时段定价,如不可,则同意8.见书后9.TC=120000+3000(q/40)+2000AC=75+122000/QMC=75AC随Q减小2个劳动组,1600元1/4, 更大的生产能力11.190万元 53元 53元 19元第七章附录练习题1、我们考查规模报酬时可由F(aK,aL)与aF(K,L)之间的关系判断当F(aK,aL)>aF(K,L),表明是规模报酬递增;当F(aK,aL)=aF(K,L),表明是规模报酬不变;当F(aK,aL)<aF(K,L),表明是规模报酬递减;(a)规模报酬递增;(b)规模报酬不变;(C)规模报酬递增。
2、根据已知条件,资本价格r=30,设劳动价格为w,则成本函数C=30K+ wL由拉格朗日函数可知,F(K,L,λ)=30K+wL-λ(100KL -1000)要使成本最小化则有:∂F(K,L, λ)/ ∂K=30-100λL =0 (1)∂F(K,L, λ)/ ∂L=w -100λK=0 (2)∂F(K,L, λ)/ ∂λ=100KL -1000 =0 (3)联立(1) ,(2), (3)可得K=(w/3) 1/2 ,L=(300/w) 1/2 ,此时成本最小,代入成本函数C=30K+ wL,得C=2(300w)1/23、根据已知条件,资本价格为r=10,劳动价格为w=15,则成本函数C=10K+ 15L由拉格朗日函数可知,F(K,L,λ)=10K+15L-λ(KL2–Q)要使成本最小化则有:∂F(K,L, λ)/ ∂K=10-λL2 =0 (1)∂F(K,L, λ)/ ∂L=15-2λKL=0 (2)∂F(K,L, λ)/ ∂λ= KL2–Q=0 (3)联立(1) ,(2), (3)可得K/L=3/4,此时成本最小,即生产既定产出的成本最小化的资本和劳动的组合为资本/劳动=3/4。
平狄克《微观经济学》课后答案 2
CHAPTER 2THE BASICS OF SUPPLY AND DEMANDThis chapter departs from the standard treatment of supply and demand basics found in most other intermediate microeconomics textbooks by discussing some of the world’s most important markets (wheat, gasoline, and automobiles) and teaching students how to analyze these markets with the tools of supply and demand.Although most of the discussion of economic theory in this chapter serves as a review, the real-world applications of this theory will be enlightening for students, particularly the material covered in Section 2.5 and Examples 2.5 and 2.6.Some problems plague the understanding of supply and demand analysis. One of the most common sources of confusion is between movements along the demand curve and shifts in demand. Through a discussion of the ceteris paribus assumption, stress that when representing a demand function (either with a graph or an equation), all other variables are held constant. Movements along the demand curve occur only with changes in price. As the omitted factors change, the entire demand function shifts. Students may also find a review of how to solve two equations with two unknowns helpful.To stress the quantitative aspects of the demand curve to students, make the distinction between quantity demanded as a function of price, Q = D(P), and the inverse demand function, where price is a function of the quantity demanded, P = D-1(Q). This may clarify the positioning of price on the Y-axis and quantity on the X-axis.Students may also question how the market adjusts to a new equilibrium. One simple mechanism is the partial-adjustment cobweb model. A discussion of the cobweb model (based on traditional corn-hog cycle or any other example) adds a certain realism to the discussion and is much appreciated by students.Although this chapter introduces demand, income, and cross-price elasticities, you may find it more appropriate to return to income and cross-price elasticity after demand elasticity is reintroduced in Chapter 4. If you wait, you should postpone Exercise (7) until income and cross-price elasticities are discussed.1. Suppose that unusually hot weather causes the demand curve for ice cream to shift to the right. Why will the price of ice cream rise to a new market-clearing level?Assume the supply curve is fixed. The unusually hot weather will cause a rightwardshift in the demand curve, creating short-run excess demand at the current price.Consumers will begin to bid against each other for the ice cream, putting upwardpressure on the price. The price of ice cream will rise until the quantity demanded andthe quantity supplied are equal.4. Why do long-run elasticities of demand differ from short-run elasticities? Consider two goods: paper towels and televisions. Which is a durable good? Would you expect the price elasticity of demand for paper towels to be larger in the short-run or in the long-run? Why? What about the price elasticity of demand for televisions?Long-run and short-run elasticities differ based on how rapidly consumers respond toprice changes and how many substitutes are available. If the price of paper towels, anon-durable good, were to increase, consumers might react only minimally in the shortrun. In the long run, however, demand for paper towels would be more elastic as newsubstitutes entered the market (such as sponges or kitchen towels). In contrast, thequantity demanded of durable goods, such as televisions, might change dramatically inthe short run following a price change. For example, the initial influence of a priceincrease for televisions would cause consumers to delay purchases because durablegoods are built to last longer. Eventually consumers must replace their televisions asthey wear out or become obsolete; therefore, we expect the demand for durables to bemore elastic in the long run.5. Explain why, for many goods, the long-run price elasticity of supply is larger than the short-run elasticity.The elasticity of supply is the percentage change in the quantity supplied divided by thepercentage change in price. An increase in price induces an increase in the quantitysupplied by firms. Some firms in some markets may respond quickly and cheaply toprice changes. However, other firms may be constrained by their production capacity inthe short run. The firms with short-run capacity constraints will have a short-runsupply elasticity that is less elastic. However, in the long run all firms can increasetheir scale of production and thus have a larger long-run price elasticity.6. Suppose the government regulates the prices of beef and chicken and sets them below their market-clearing levels. Explain why shortages of these goods will develop and what factors will determine the sizes of the shortages. What will happen to the price of pork? Explain briefly.If the price of a commodity is set below its market-clearing level, the quantity that firmsare willing to supply is less than the quantity that consumers wish to purchase. Theextent of the excess demand implied by this response will depend on the relativeelasticities of demand and supply. For instance, if both supply and demand are elastic,the shortage is larger than if both are inelastic. Factors such as the willingness ofconsumers to eat less meat and the ability of farmers to change the size of their herdsand produce less determine these elasticities and influence the size of excess demand.Rationing will result in situations of excess demand when some consumers are unableto purchase the quantities desired. Customers whose demands are not met willattempt to purchase substitutes, thus increasing the demand for substitutes and raisingtheir prices. If the prices of beef and chicken are set below market-clearing levels, theprice of pork will rise.7. In a discussion of tuition rates, a university official argues that the demand for admission is completely price inelastic. As evidence she notes that while the university has doubled its tuition (in real terms) over the past 15 years, neither the number nor quality of students applying has decreased. Would you accept this argument? Explain briefly. (Hint: The official makes an assertion about the demand for admission, but does she actually observe a demand curve? What else could be going on?)If demand is fixed, the individual firm (a university) may determine the shape of thedemand curve it faces by raising the price and observing the change in quantity sold.The university official is not observing the entire demand curve, but rather only theequilibrium price and quantity over the last 15 years. If demand is shifting upward, assupply shifts upward, demand could have any elasticity. (See Figure 2.7, for example.)Demand could be shifting upward because the value of a college education hasincreased and students are willing to pay a high price for each opening. More marketc. A drought shrinks the apple crop to one-third its normal size.The supply curve would shift in, causing the equilibrium price to rise and theequilibrium quantity to fall.d. Thousands of college students abandon the academic life to become apple pickers.The increased supply of apple pickers will lead to a decrease in the cost of bringingapples to market. The decreased cost of bringing apples to market results in anoutward shift of the supply curve of apples and causes the equilibrium price to fall andthe equilibrium quantity to increase.e. Thousands of college students abandon the academic life to become apple growers.This would result in an outward shift of the supply curve for apples, causing theequilibrium price to fall and the equilibrium quantity to increase.1. Consider a competitive market for which the quantities demanded and supplied (per year) at various prices are given as follows:Price($)Demand (millions) Supply (millions) 6022 14 8020 16 10018 18 12016 20 a. Calculate the price elasticity of demand when the price is $80. When the price is$100.We know that the price elasticity of demand may be calculated using equation 2.1 fromthe text:E Q Q P PP Q Q PD D D D D ==∆∆∆∆. With each price increase of $20, the quantity demanded decreases by 2. Therefore,∆∆Q P DF HG I K J =-=-22001.. At P = 80, quantity demanded equals 20 andE D =F HG I KJ -=-802001040...b g Similarly, at P = 100, quantity demanded equals 18 andE D =F HG I K J -=-1001801056...b g b. Calculate the price elasticity of supply when the price is $80. When the price is $100.The elasticity of supply is given by:E Q Q P P Q Q PS S S S S ==∆∆∆∆. With each price increase of $20, quantity supplied increases by 2. Therefore,∆∆Q SF HG I K J ==22001.. At P = 80, quantity supplied equals 16 andE S =F HG I KJ =80160105..bg .Similarly, at P = 100, quantity supplied equals 18 andE S=FH GIK J= 1001801056...bgc. What are the equilibrium price and quantity?The equilibrium price and quantity are found where the quantity supplied equals thequantity demanded at the same price. As we see from the table, the equilibrium priceis $100 and the equilibrium quantity is 18 million.d. Suppose the government sets a price ceiling of $80. Will there be a shortage, and, ifso, how large will it be?With a price ceiling of $80, consumers would like to buy 20 million, but producers willsupply only 16 million. This will result in a shortage of 4 million.2. Refer to Example 2.3 on the market for wheat. Suppose that in 1985 the Soviet Union hadbought an additional 200 million bushels of U.S. wheat. What would the free market price of wheat have been and what quantity would have been produced and sold by U.S. farmers?The following equations describe the market for wheat in 1985:QS= 1,800 + 240PandQD= 2,580 - 194P.If the Soviet Union had purchased an additional 200 million bushels of wheat, the newdemand curve 'Q D, would be equal to Q ED + 200, or'Q D= (2,580 - 194P) + 200 = 2,780 - 194PEquating supply and the new demand, we may determine the new equilibrium price,1,800 + 240P = 2,780 - 194P, or434P = 980, or P* = $2.26 per bushel.To find the equilibrium quantity, substitute the price into either the supply or demandequation, e.g.,QS= 1,800 + (240)(2.26) = 2,342andQD= 2,780 - (194)(2.26) = 2,342.3. The rent control agency of New York City has found that aggregate demand is QD= 100 - 5P measured in tens of thousands of apartments, and price, the average monthly rental rate, P, with quantity measured in hundreds of dollars. The agency also noted that the increase in Q at lower P results from more three-person families coming into the city from Long Island and demanding apartments. The city’s board of realtors acknowledges that this is agood demand estimate and has shown that supply is QS= 50 + 5P.a. If both the agency and the board are right about demand and supply, what is the freemarket price? What is the change in city population if the agency sets a maximum average monthly rental of $100, and all those who cannot find an apartment leave the city?To find the free market price for apartments, set supply equal to demand:100 - 5P = 50 + 5P, or P = $500.Substituting the equilibrium price into either the demand or supply equation todetermine the equilibrium quantity:QD= 100 - (5)(5) = 75andQ S = 50 + (5)(5) = 75.We find that at the rental rate of $500, 750,000 apartments are rented.If the rent control agency sets the rental rate at $100, the quantity supplied would thenbe 550,000 (Q S = 50 + (5)(100) = 550), a decrease of 200,000 apartments from the freemarket equilibrium. (Assuming three people per family per apartment, this wouldimply a loss of 600,000 people.) At the $100 rental rate, the demand for apartments is950,000 units, and the resultant shortage is 400,000 units.b. Suppose the agency bows to the wishes of the board and sets a rental of $900 permonth on all apartments to allow landlords a “fair” rate of return. If 50 percent of any long-run increases in apartment offerings comes from new construction, how many apartments are constructed?At a rental rate of $900, the supply of apartments would be 50 + 5(9) = 95, or 950,000units, which is an increase of 200,000 units over the free market equilibrium.Therefore, (0.5)(200,000) = 100,000 units would be constructed. Note, however, thatsince demand is only 550,000 units, 400,000 units would go unrented.4. Much of the demand for U.S. agricultural output has come from other countries. From Example 2.3, total demand is Q = 3,550 - 266P . In addition, we are told that domestic demand is Q d = 1,000 - 46P . Domestic supply is Q S = 1,800 + 240P . Suppose the export demand for wheat falls by 40 percent.a. U.S. farmers are concerned about this drop in export demand. What happens to thefree market price of wheat in the United States? Do the farmers have much reason to worry?Given total demand, Q = 3,550 - 266P , and domestic demand, Q d = 1,000 - 46P , we maysubtract and determine export demand, Q e = 2,550 - 220P .The initial market equilibrium price is found by setting total demand equal to supply:3,550 - 266P - 1,800 + 240P , orP = $3.46.There are two different ways to handle the 40 percent drop in demand. One way is toassume that the demand curve shifts down so that at all prices demand decreases by 40percent. The second way is to rotate the demand curve in a clockwise manner aroundthe vertical intercept (i.e. in the current case the demand curve would becomeQ = 3,550 - 159.6P ). We apply the former approach in the solution to exercises here.Regardless of the two approaches, the effect on prices and quantity will be qualitativelythe same, but will differ quantitatively.Therefore, if export demand decreases by 40 percent, total demand becomesQ D = Q d + 0.6Q e = 1,000 - 46P + (0.6)(2,550 - 220P ) = 2,530 - 178P .Equating total supply and total demand,1,800 + 240P = 2,530 - 178P , orP = $1.75,which is a significant drop from the market-clearing price of $3.46 per bushel. At thisprice, the market-clearing quantity is 2,219 million bushels. Total revenue hasdecreased from $9.1 billion to $3.9 billion. Most farmers would worry.b. Now suppose the U.S. government wants to buy enough wheat each year to raise theprice to $3.00 per bushel. Without export demand, how much wheat would the government have to buy each year? How much would this cost the government?With a price of $3, the market is not in equilibrium. Demand = 1000 - 46(3) = 862.Supply = 1800 + 240(3) = 2,520, and excess supply is therefore 2,520 - 862 = 1,658. Thegovernment must purchase this amount to support a price of $3, and will spend $3(1.66million) = $5.0 billion per year.5. In Example 2.6 we examined the effect of a 20 percent decline in copper demand on the price of copper, using the linear supply and demand curves developed in Section 2.5. Suppose the long-run price elasticity of copper demand were -0.4 instead of -0.8.a. Assuming, as before, that the equilibrium price and quantity are P* = 75 cents perpound and Q* = 7.5 million metric tons per year, derive the linear demand curve consistent with the smaller elasticity.Following the method outlined in Section 2.5, we solve for a and b in the demandequation Q D = a - bP . First, we know that for a linear demand function E b P D =-F H G I KJ *. Here E D = -0.4 (the long-run price elasticity), P* = 0.75 (the equilibrium price), and Q* =7.5 (the equilibrium quantity). Solving for b , -=-F H I K0407575...b , or b = 4. To find the intercept, we substitute for b , Q D (= Q *), and P (= P *) in the demandequation:7.5 = a - (4)(0.75), or a = 10.5.The linear demand equation consistent with a long-run price elasticity of -0.4 isthereforeQ D = 10.5 - 4P .b. Using this demand curve, recalculate the effect of a 20 percent decline in copperdemand on the price of copper.The new demand is 20 percent below the original (using our convention that the wholedemand curve is shifted down by 20 percent):'Q D =-=-0810548432....a f a fP P . Equating this to supply,8.4 - 3.2P = -4.5 + 16P , orP = 0.672.With the 20 percent decline in the demand, the price of copper falls to 67.2 cents perpound.6. Example 2.7 analyzes the world oil market. Using the data given in that example,a. Show that the short-run demand and competitive supply curves are indeed given byD = 24.08 - 0.06PS C = 11.74 + 0.07P .First, considering non-OPEC supply:S c = Q * = 13.With E S = 0.10 and P * = $18, E S = d (P */Q *) implies d = 0.07.Substituting for d , S c , and P in the supply equation, c = 11.74 and S c = 11.74 + 0.07P .Similarly, since Q D = 23, E D = -b (P */Q *) = -0.05, and b = 0.06. Substituting for b , Q D = 23, and P = 18 in the demand equation gives 23 = a - 0.06(18), so that a = 24.08.Hence Q D = 24.08 - 0.06P .b. Show that the long-run demand and competitive supply curves are indeed given byD = 32.18 - 0.51PS C = 7.78 + 0.29P .As above, E S = 0.4 and E D = -0.4: E S = d (P */Q *) and E D = -b(P*/Q*), implying 0.4 = d (18/13)and -0.4 = -b (18/23). So d = 0.29 and b = 0.51.Next solve for c and a :S c = c + dP and Q D = a - bP , implying 13 = c + (0.29)(18) and 23 = a - (0.51)(18).So c = 7.78 and a = 32.18.c. Use this model to calculate what would happen to the price of oil in the short-runand the long-run if OPEC were to cut its production by 6 billion barrels per year.With OPEC’s supply reduced from 10 bb/yr to 4 bb/yr, add this lower supply of 4 bb/yr to the short-run and long-run supply equations:S c ' = 4 + S c = 11.74 + 4 + 0.07P = 15.74 + 0.07P and S " = 4 + S c = 11.78 + 0.29P .These are equated with short-run and long-run demand, so that:15.74 + 0.07P = 24.08 - 0.06P ,implying that P = $64.15 in the short run; and11.78 + 0.29P = 32.18 - 0.51P ,implying that P = $24.29 in the long run.7.Refer to Example 2.8, which analyzes the effects of price controls on natural gas. a. Using the data in the example, show that the following supply and demand curvesdid indeed describe the market in 1975:Supply: Q = 14 + 2P G + 0.25P ODemand: Q = -5P G + 3.75P Owhere P G and P O are the prices of natural gas and oil, respectively. Also, verify that if the price of oil is $8.00, these curves imply a free market price of $2.00 for natural gas.To solve this problem, we apply the analysis of Section 2.5 to the definition of cross-price elasticity of demand given in Section 2.3. For example, the cross-price-elasticity of demand for natural gas with respect to the price of oil is:E Q P P Q GO G O G G=F HG I K J FH GI KJ ∆∆. ∆∆Q P G O F H G IK J is the change in the quantity of natural gas demanded, because of a small change in the price of oil. For linear demand equations,∆∆Q P G O F H G I K J is constant. If we represent demand as:Q G = a - bP G + eP O(notice that income is held constant), then∆∆Q P G OF HG I K J = e . Substituting this into the cross-price elasticity, E e P Q PO O G=F H G I K J **, where P O * and Q G * are the equilibrium price and quantity. We know that P O * = $8 and Q G* = 20 trillion cubic feet (Tcf). Solving for e , 15820.=F H G I KJ e , or e = 3.75. Similarly, if the general form of the supply equation is represented as:Q G = c + dP G + gP O , the cross-price elasticity of supply is g P Q OG**F H G I K J , which we know to be 0.1. Solving for g , ⎪⎭⎫ ⎝⎛=2081.0g , or g = 0.25. The values for d and b may be found with equations 2.5a and 2.5b in Section 2.5. Weknow that E S = 0.2, P* = 2, and Q* = 20. Therefore,⎪⎭⎫ ⎝⎛=2022.0d , or d = 2.Also, E D = -0.5, so⎪⎭⎫ ⎝⎛=-2025.0b , or b = -5. By substituting these values for d, g, b , and e into our linear supply and demandequations, we may solve for c and a :20 = c + (2)(2) + (0.25)(8), or c = 14,and20 = a - (5)(2) + (3.75)(8), or a = 0.If the price of oil is $8.00, these curves imply a free market price of $2.00 for naturalgas. Substitute the price of oil in the supply and demand curves to verify theseequations. Then set the curves equal to each other and solve for the price of gas.14 + 2P G + (0.25)(8) = -5P G + (3.75)(8), 7P G = 14, orP G = $2.00.b. Suppose the regulated price of gas in 1975 had been $1.50 per million cubic feet,instead of $1.00. How much excess demand would there have been?With a regulated price of $1.50 for natural gas and a price of oil equal to $8.00 perbarrel,Demand: Q D = (-5)(1.50) + (3.75)(8) = 22.5, andSupply: Q S = 14 + (2)(1.5) + (0.25)(8) = 19.With a supply of 19 Tcf and a demand of 22.5 Tcf, there would be an excess demand of3.5 Tcf.c. Suppose that the market for natural gas had not been regulated. If the price of oilhad increased from $8 to $16, what would have happened to the free market price of natural gas?If the price of natural gas had not been regulated and the price of oil had increasedfrom $8 to $16, thenDemand: Q D = -5P G + (3.75)(16) = 60 - 5P G , andSupply: Q S = 14 + 2P G + (0.25)(16) = 18 + 2P G .Equating supply and demand and solving for the equilibrium price,18 + 2P G = 60 - 5P G , or P G = $6.The price of natural gas would have tripled from $2 to $6.。
平狄克微观经济学课后习题答案中文
第一章复习题1.市场是通过相互作用决定一种或一系列产品价格的买卖双方的集合,因此可以把市场看作决定价格的场所。
行业是出售相同的或紧密相关的产品的厂商的集合,一个市场可以包括许多行业。
2.评价一个理论有两个步骤:首先,需要检验这个理论假设的合理性;第二,把该理论的预测和事实相比较以此来验证它。
如果一个理论无法被检验的话,它将不会被接受。
因此,它对我们理解现实情况没有任何帮助。
3.实证分析解释“是什么”的问题,而规范分析解释的是“应该是什么”的问题。
对供给的限制将改变市场的均衡。
A中包括两种分析,批评这是一种“失败的政策”——是规范分析,批评其破坏了市场的竞争性——是实证分析。
B向我们说明在燃油的配给制下总社会福利的被损坏——是实证分析。
4.由于两个市场在空间上是分离的,商品在两地间的运输是套利实现的条件。
如果运输成本为零,则可以在Oklahoma购买汽油,到New Jersey出售,赚取差价;如果这个差价无法弥补运输成本则不存在套利机会。
5.商品和服务的数量与价格由供求关系决定。
鸡蛋的实际价格从1970年至1985年的下降,一方面是由于人们健康意识的提高而导致鸡蛋需求的减少,同时也因为生产成本的降低。
在这两种因素下,鸡蛋的价格下降了。
大学教育的实际价格的升高,是由于越来越多的人倾向于获得大学教育而导致需求提高,同时教育的成本也在升高。
在这两方面因素作用下,大学教育费用提高了。
6.日圆相对美圆来说,价值升高,升值前相比,兑换同样数量的日圆需要付出更多的美圆。
由汇率的变化引起购买力的变化,在日本市场出售的美国汽车,由于美圆贬值日圆升值,持有日圆的消费者将较以前支付较底的价格;而在美国市场出售的日本汽车,由于日圆升值美圆贬值,持有美圆的消费者将面对较以前提高的价格。
4.长期弹性和短期弹性区别在于消费者对价格变化的反映速度以及可获得的替代品。
对纸巾这样的非耐用品,价格上升,消费者在短期内的反映很小。
但在长期,对纸巾的需求将会变得富有弹性。
平狄克微观经济学答案第1-3章11页word
第一章复习题1.市场是通过相互作用决定一种或一系列产品价格的买卖双方的集合,因此可以把市场看作决定价格的场所。
行业是出售相同的或紧密相关的产品的厂商的集合,一个市场可以包括许多行业。
2.评价一个理论有两个步骤:首先,需要检验这个理论假设的合理性;第二,把该理论的预测和事实相比较以此来验证它。
如果一个理论无法被检验的话,它将不会被接受。
因此,它对我们理解现实情况没有任何帮助。
3.实证分析解释“是什么”的问题,而规范分析解释的是“应该是什么”的问题。
对供给的限制将改变市场的均衡。
A中包括两种分析,批评这是一种“失败的政策”——是规范分析,批评其破坏了市场的竞争性——是实证分析。
B向我们说明在燃油的配给制下总社会福利的被损坏——是实证分析。
4.由于两个市场在空间上是分离的,商品在两地间的运输是套利实现的条件。
如果运输成本为零,则可以在Oklahoma购买汽油,到New Jersey出售,赚取差价;如果这个差价无法弥补运输成本则不存在套利机会。
5.商品和服务的数量与价格由供求关系决定。
鸡蛋的实际价格从1970年至1985年的下降,一方面是由于人们健康意识的提高而导致鸡蛋需求的减少,同时也因为生产成本的降低。
在这两种因素下,鸡蛋的价格下降了。
大学教育的实际价格的升高,是由于越来越多的人倾向于获得大学教育而导致需求提高,同时教育的成本也在升高。
在这两方面因素作用下,大学教育费用提高了。
6.日圆相对美圆来说,价值升高,升值前相比,兑换同样数量的日圆需要付出更多的美圆。
由汇率的变化引起购买力的变化,在日本市场出售的美国汽车,由于美圆贬值日圆升值,持有日圆的消费者将较以前支付较底的价格;而在美国市场出售的日本汽车,由于日圆升值美圆贬值,持有美圆的消费者将面对较以前提高的价格。
第二章复习题1.假设供给曲线固定,炎热天气通常会引起需求曲线右移,在当前价格上造成短期需求过剩。
消费者为获得冰激凌,愿意为每一单位冰激凌出价更高。
平狄克 中级微观经济学第一章课后练习答案_Ch01
Oklahoma and New Jersey represent separate geographic markets for gasoline because of high transportation costs.There would be an opportunity for arbitrage if transportation costs were less
In general, the first class is a good time to pique student interest in the course.It is also a good time to tell students that they need to work hard to learn how to do economic analysis, and that memorization alone will not get them through the course.Students must learn to think like economists, so encourage them to work lots of problems.Also encourage them to draw graphs neatly and large enough to make them easy to interpret.It always amazes me to see the tiny, poorly drawn graphs some students produce.It is no wonder their answers are often incorrect.You might even suggest they bring a small ruler and colored pencils to class as they can draw good diagrams.
平狄克微观经济学(第7版)习题详解(第7篇生成成本)
平狄克微观经济学(第7版)习题详解(第7篇生成成本)平狄克《微观经济学》(第7版)第7章生产成本课后复习题详解1.某公司支付给会计人员10000美元的年薪,这笔费用是一项经济成本吗?答:这笔费用是一项经济成本。
经济成本是显性成本和隐性成本之和。
显性成本指实际支出,所有涉及到货币交易行为的成本都属于显性成本。
隐性成本是一种经济成本,不涉及到货币交易行为,但涉及到生产中所使用的资源的成本。
当一个公司支付给会计人员10000美元年薪时,这是一笔货币交易,这笔费用是会计人员用劳动换来的收入。
因此,这笔费用属于经济成本中的显性成本。
2.某小零售店女店主自己做账,你将如何计算她工作的机会成本?答:该店主自己做账的机会成本是:她利用做账的时间和精力做其他事情时所能获得的最大收入。
根据机会成本的定义,如果该小零售店女店主不是自己做账,她可以在这段时间里做其他的事情,例如做小生意或者参加一些休闲活动。
那么,女店主自己做账的机会成本就是她用于做账的时间做其他事情时所能获得的最大收入。
3.解释以下说法正确与否:(1)如果一家企业的拥有者不给自己支付工资,则会计成本为零,而经济成本为正。
(2)会计利润为正的企业不一定经济利润也为正。
(3)企业雇佣了一些目前处于失业状态的工人,则其使用这些工人服务的机会成本为零。
答:(1)正确。
因为这里不存在货币交易,所以不存在会计成本(或显性成本)。
但是,因为企业的拥有者可以受雇于其他企业,因而存在经济成本。
经济成本为正,反映了此人工作时间的机会成本。
(2)正确。
会计利润仅考虑显性成本。
对于企业而言,可能还存在某些机会成本,这些机会成本没有像显性成本那样完全实现,所以对于会计利润为正的企业,有可能加进这些机会成本之后,经济利润为负。
这意味着企业没有最有效地利用其资源。
(3)错误。
机会成本衡量了这些工人的时间价值,因而不可能为零。
对于工人而言,尽管工人目前处于失业状态,但是他们仍掌握一定的技能,这些技能具有价值,进入某一企业工作意味着他们放弃了去另一家企业工作,或者利用时间在家照顾老人或孩子的机会,这些可能的选择使得雇佣工人的机会成本大于零。
平狄克微观经济学第六版第十四章课后答案
平狄克微观经济学第六版第十四章课后答案平狄克微观经济学第六版课后答案***** 14***** FOR FACTOR INPUTSThe following two chapters examine the markets for labor and capital. Although the discussion in this chapter is general, most of the examples refer to labor as the only variable input to production, with the exception of Example 14.1, which discusses “The Demand for Jet Fuel” by airlines. Labor demand and supply are discussed in the first section, and the competitive factor market equilibrium and economic rent are discussed in the second section. Section 14.3 explores the factor market structure for the case where the buyer has monopsony power, and section 14.4 explores the case of monopoly power on the part of the seller of the factor.An understanding of this chapter relies on concepts from Chapters 4 through 8 and 10. If you have just covered Chapters 11-13, you might begin by reviewing marginal product, marginalrevenue, and cost minimization. You should then discuss marginal revenue product and the profit-maximizing condition MRPL = w. Explain why we are only interested in the portion of the MP curve below the average product curve (the downward-sloping portion). The derivation of the firm’s demand curve for labor is straightforward when labor is the only factor, but becomes more complicated when there are several variable inputs. In particular, you might explain why the MRPL curve shifts as the firm substitutes one input for another in production in response to a price change by noting that the MRPL curve is drawn for a fixed level of the other variable input.When presenting the market labor demand curve, explain that since the input prices change as more inputs are demanded, the market demand curve is not simply the summation of individual demand curves. You can extend the presentation of price elasticity of input demand (see Example 14.1) by discussing the conditions leading to price sensitivity. Elasticity is greater (1) when the elasticity of demand for the product is higher, (2) when it is easy to substitute one input for another, and (3) when the elasticity of supply is higher for other inputs. Elasticity of supply, which was discussed in Chapter 2, is reintroduced in Example 14.2.You should also distinguish between short-run and long-run elasticity (see Figure 14.6).If you have already covered substitution and income effects, the students will be ready for the derivation of the backward-bending supply curve for labor. Although Figure 14.9 is a straightforward application of these tools, students are often confused by the plotting of income against leisure. Point out that this is just another type of utility maximization problem where the two goods are leisure and income. Income can be thought of as the consumption of goods other than leisure, in that more income buys more goods. You can also implicitly assume that the price of other goods is $1 and the price of leisure is the wage. The supply of labor curve is derived by changing the wage and finding the new level of hours worked. An individual’s supply curve of labor is backward bending only when the income effect dominates the substitution effect and leisure is a normal good. Show typical supply curves for each group in Table 14.2. For an experimental study of the labor-leisure trade-off see Battalio, Green, and Kagel, “Income-Leisure Tradeoff of Animal Workers,” American Economic Review (September 1981).Section 14.2 brings together labor demand and supply forboth competitive and monopolistic Although economic rent was presented in Chapter 8, it is reintroduced with more detail here. In Section 14.3, carefully explain why the marginal expenditure curve is above the average expenditure curve for a monopsonist (see Figure 14.14). You can discuss how a monopsonist would price discriminate, e.g., pay a different wage rate to each employee. With perfect price discrimination, the marginal revenue expenditure curve would coincide with the average expenditure curve. Although monopsony exists in some markets, the exercise of monopsony power is rare because of factor mobility. However, the employment of athletes by the owners of professional teams provides a good example (see Example 14.4 “Monopsony Power in the Market for Baseball Players”). On this same topic, see Sommers and Quinton, “Pay and Performance in Major League Baseball: The Case of the First Family of Free Agents,” Journal of Hu man Resources (Summer 1982). Section 14.4 discusses the case of unions to explore monopoly power on the part of the seller of the input.平狄克微观经济学第六版课后答案1. Why is a firm’s demand for labor curve more inelastic when the firm has monopoly power in the output market than when thefirm is producing competitively?The firm’s demand curve for labor is determined by the incremental revenue fromhiring an additional unit of labor known as the marginal revenue product of labor:MRPL = (MPL)(MR), the additional output (“product”) that the last worker produced,times the additional revenue earned by selling that output. In a competitive industry,the marginal revenue curve is perfectly elastic and equal to price. For a monopolist,marginal revenue is downward sloping. As more labor is hired and more output isproduced, the monopolist will charge a lower price and marginal revenue will diminish.All else the same, marginal revenue product will be smaller for the monopolist. Thisimplies that the marginal revenue product for the monopolist is more inelastic than forthe competitive firm.2. Why might a labor supply curve be backward bending?A backward-bending supply curve for labor may occur when the income effect of anincrease in the wage rate dominates the substitution effect. Labor supply decisions aremade by individuals choosing the most satisfying combination of work and other(leisure) activities. With a larger income, the individual can afford to work fewerhours: the income effect. As the wage rate increases, the value of leisure time (theopportunity cost of leisure) increases, thus inducing the individual to work longer hours:the substitution effect. Because the two effects work in opposite directions, the shapeof an individual’s labor supply curve depends on the individual’s preferences for income,consumption, and leisure.3. How is a computer company’s demand for computer programmers a derived demand?A computer c ompany’s demand for inputs, including programmers, depends on howmany computers it sells. The firm’s demand for programming labor depends on (isderived from) the demand it faces in its market for computers. As demand forcomputers shifts, the demand for programmers shifts.4. Compare the hiring choices of a monopsonistic and a competitive employer of workers. Which will hire more workers, and which will pay the higher wages? Explain.Since the decision to hire another worker means the monopsonist must pay a higherwage for all workers, and not just the last worker hired, its marginal expenditure curvelies above the input supply curve (the average expenditure curve). The monopsonist’sprofit-maximizing input demand, where the marginal expenditure curve intersects themarginal revenue product curve, will be less than the competitor’s profit-maximizinginput choice, where the average expenditure curve intersects the demand curve. Themonopsonist hires less labor, and the wage paid will be lessthan in a competitivemarket.5. Rock musicians sometimes earn over $1 million per year. Can you explain such large incomes in terms of economic rent?Economic rent is the difference between the actual payment to the factor of productionand the minimum amount that the factor is willing to accept. In this case, you mightassume that there are a limited number of top-quality rock musicians who will continueto play rock music no matter what they are paid. This results in a perfectly inelasticsupply curve, or something close to it. Given the high demand for rock music, thewage will be very high and there will be a lot of economic rent. If there was a largersupply of top-quality rock musicians, or a more elastic supply, then the economic rentwould be smaller.平狄克微观经济学第六版课后答案6. What happens to the demand for one input when the useof a complementary input increases?If the demand for the complementary input increases, the demand for the given inputwill increase as well. When demand for the complementary input increases, there isan increase in the quantity hired and possibly the price paid. Both of these changeswill increase the MRP of the given input, and hence will increase the quantity hiredand possibly the price paid. Whether the prices of the inputs increases depends on thedegree of monopsony power on the part of the firm.7. For a monopsonist, what is the relationship between the supply of an input and the marginal expenditure on it?The decision to increase employment means the monopsonist must pay all units thehigher price, and not just the last unit hired. Therefore, its marginal expenditurecurve lies above the input supply curve (the average expenditure curve). Hiring morelabor will increase the marginal expenditure, which willincrease the averageexpenditure. If the average expenditure is increasing, then the marginal expendituremust be greater than the average expenditure.8. Currently the National Football League has a system for drafting college players by which each player is picked by only one team. The player must sign with that team or not play in the league. What would happen to the wages of newly drafted and more experienced football players if the draft system were repealed, and all teams could compete for college players?The National Football League draft and reserve clause (a primary issue in the 1987-1988 season’s strike) creates a monopsoni st cartel among the owners of NFL teams. Ifthe draft system were repealed, competition among teams would increase wages offootball players to the point where the marginal revenue product of each player wouldbe equal to the player’s wage.9. The government wants to encourage individuals on welfare to become employed. It is considering two possibleincentive programs for firms.A. Give the firm $2 per hour for every individual on welfare who is hired.B. Give each firm that hires one or more welfare workers a payment of $1000 per year, irrespective of the number of hires.To what extent is each of these programs likely to be effective at increasing the employment opportunities for welfare workers?Firms will hire additional labor as long as the extra benefit is greater than the extracost of hiring the worker, or until MRPL = w. Option A would be effective because ifthe firm receives $2 per hour for every welfare worker hired then the effective wagepaid, w, will fall and the firm will find it optimal to hire more labor until the benefits(MRPL) again equal the costs (w) at the margin. Option B would be effective atincreasing employment opportunities also in that if the firm hires an individual whohas been on welfare they will then receive $1000. However,plan B is notnecessarily as effective as plan A given the firm only receives one lump sum paymentregardless of the number of welfare workers hired. In this case the firm only has anincentive to hire the one welfare worker, though they may of course choose to hiremore than one welfare worker.10. A small specialty cookie company, whose only variable input is labor, finds that the average worker can produce 50 cookies per day, the cost of the average worker is $64 per day, and the price of a cookie is $1. Is the cookie company maximizing its profit? Explain.The marginal product of labor is 50 (cookies per day) and the price per cookie is 1($ per cookie) so the marginal revenue product is $50/day. Since this is less than thewage of $64 per day the cookie company is not maximizing profit. They are平狄克微观经济学第六版课后答案employing too much labor since the cost of labor is greaterthan the benefit of labor atthe margin, and are therefore producing too many cookies.11. A firm uses both labor and machines in production. Explain why an increase in the average wage rate causes both a movement along the labor demand curve and a shift of the curve.An increase in the wage rate causes an upward movement along the labor demandcurve. For any given marginal revenue product curve, the firm will find that theywant to hire fewer workers when the wage increases (an upward movement).However, when the wage increases the marginal cost will increase which will reducedesired output. When output falls, the firm will not need as many machines and themarginal product of labor curve will shift to the left, assuming machines and laborare complementary. This will also reduce the demand for labor.1. Suppose that the wage rate is $16 per hour, and the price of the product is $2. Values for output and labor are in units perhour.203547576570a. 0 1 2 3 4 5 6 Find the profit-maximizing quantity of labor.From the information given above, calculate the marginal product of labor, the extraoutput produced by hiring one more unit of labor, and then multiply by price to getthe marginal revenue product of labor. To find the profit-maximizing quantity oflabor, use the rule that the firm wants to hire labor only as long as the marginalrevenue product of labor is greater than the nominal wage, or up to the point wherethe marginal revenue product of labor is equal to the nominal wage. From thetable below, the firm will hire 5 units of labor.b. Suppose that the price of the product remains at $2 but that the wage rateincreases to $21. Find the new profit-maximizing quantity of labor.The above table does not change for this part of the problem. However, the firm nolonger wants to hire 5 units of labor because the benefit of the 5th unit ($16 per hour)is less than the cost of the 5th unit ($21 per hour). The firm would only hire 3 units平狄克微观经济学第六版课后答案of labor per hour since in this case the benefit still exceeds the cost at the margin.The firm would stick with 3 units instead of 4 unless fractional units are possible.At L=4 the cost is greater than the benefit so you lose profit by hiring the 4th unit oflabor.c. Suppose the price of the product increases to $3 and the wage remains at $16 perhour. Find the new profit-maximizing quantity of labor.A change in the price of the product will not change the marginal product of labor,but it will change the marginal revenue product of labor. The new marginal revenueproduct of labor is given in the table below. The firm will still want to hire 5 units oflabor, as in part a above. It will not hire the 6th unit because the extra benefit is lessthan the extra cost. Profit will be greater than in part a.d. Suppose that the price of the product remains at $2 and the wage remains at $16,but there is a technological breakthrough that increases output by 25% for any given level of labor. Find the new profit-maximizing quantity of labor.The technological breakthrough changes the number of units of output produced by agiven number of units of labor, and hence changes the marginal product and themarginal revenue product of labor. The new output values are found by multiplyingthe old values by 1.25. This new information is given in thetable below. The firmwill still choose to hire 5 units of labor. Profit will be greater than in part a.2. Assume that workers whose incomes are less than $10,000 currently pay no federal income taxes. Suppose a new government program guarantees each worker $5,000, whether or not he or she earns any income. For all earned income up to $10,000, the worker must pay a 50-percent tax. Draw the budget line facing the workers under this new program. How is the program likely to affect the labor supply curve of workers?The budget line for workers under this program is a straight line at $5,000. This lineis shown in the figure and table below. Workers earn $5,000 whether they work or not.平狄克微观经济学第六版课后答案6,0007,0008,0009,00010,000 3,000 3,500 4,000 4,500 5,000 2,000 1,500 1,000 500 0 5,000 5,000 5,000 5,000 5,0003. Using your knowledge of marginal revenue product, explain the following:a. A famous tennis star is paid $100,000 for appearing in a 30-second televisioncommercial. The actor who plays his doubles partner is paid $500.Marginal revenue product of labor, MRPL, is equal to marginal revenue from anincremental unit of output multiplied by the marginal product from an incrementalunit of labor, or in other words, the extra revenue generated by having the tennis starappear in the ad. The famous tennis star is able to help increase revenues far morethan the actor, so he is paid much more than the actor. The wage of the actor isdetermined by the supply and demand of actors willing to play tennis with tennis stars.平狄克微观经济学第六版课后答案b. The president of an ailing savings and loan is paid not to stay in his job for the lasttwo years of his contract.The marginal revenue product of the president of the ailing savings and loan is likely tobe negative and therefore, the savings and loan is better off by paying the president notto show up. They have calculated that they will lose less (or gain more) by paying thepresident off and hiring someone else.c. A jumbo jet carrying 400 passengers is priced higher than a 250-passenger modeleven though both aircraft cost the same to manufacture.The ability of the larger jet to generate more revenue increases its value to the airline,and therefore the airline is willing to pay more for it.4. The demands for the factors of production listed below have increased. What can you conclude about changes in the demand for the related consumer goods? If demands for the consumer goods remain unchanged, what other explanation is there for an increase in derived demands for these items?a. Computer memory chipsIn general, an increase in the demand for a good increasesthe demand for its factorinputs. The converse is not necessarily true; i.e., an increase in the demand for factorinputs does not necessarily imply an increase in the demand for the final product. Thedemand for an input may increase due to a change in the use of other inputs in theproduction process. As the price of another input increases, its demand falls and thedemand of substitutable inputs rises. In this case, the increase in the demand forcomputer memory chips must have been caused by an increase in the demand forpersonal computers given that computer memory chips are used only in computers, andthere are no substitutes for computer memory chips.b. Jet fuel for passenger planesWith an increase in the demand for jet travel, the demand for jet fuel will increase.There are no substitutes for jet fuel.c. Paper used for newsprintGiven the paper is being used to print newspapers then there must have been anincrease in the circulation of newspapers.d. Aluminum used for beverage cansWith an increase in demand for cold drinks in the summer, the seasonal demand foraluminum increases, so this is one possible explanation. Alternatively, if glass orplastic have become more expensive then this may affect the demand for aluminum.Finally, changes in the market for recycled aluminum may affect the demand for newaluminum.5. Suppose there are two groups of workers, unionized and nonunionized. Congress passes a law that requires all workers to join the union. What do you expect to happen to the wage rates of formerly nonunionized workers? of those workers who were originally unionized? What have you assumed about the union’s behavior?In general, we expect that nonunionized workers are earning lower wages thanunionized workers. If all workers are forced to join the union, it would be reasonableto expect that the nonunionized workers will now receive higher wages and theunionized workers will receive a wage that could go either way. There are a couple ofitems to consider. First, the union now has more monopoly power in that there are nononunion workers to act as substitutes for union workers. This gives more power tothe union, which means higher wages can in general be negotiated. However, the unionnow has more members to satisfy. If wages are kept at a high level, there will be fewerjobs, and hence some previously nonunionized workers may end up with no job. Theunion may wish to trade off some of the wage for a guarantee of more jobs. The平狄克微观经济学第六版课后答案average income of all workers will rise if labor demand is inelastic and will fall if labordemand is elastic.平狄克微观经济学第六版课后答案implications of the government’s monopsony power: fewer soldiers are hired, and theyare paid less than their marginal product. When a mandatory draft is implemented,even fewer professional soldiers are hired. Wages for volunteer soldiers fall, pusheddown by the fact that wages of the draftees can be very low.8. The demand for labor by an industry is given by the curve L = 1200 - 10w, where L is the labor demanded per day and w is the wage rate. The supply curve is given by L = 20w. What is the equilibrium wage rate and quantity of labor hired? What is the economic rent earned by workers?The equilibrium wage rate is determined where quantity of labor supplied is equal tothe quantity of labor demanded:20w = 1,200 - 10w, or w = $40.平狄克微观经济学第六版课后答案Substituting into either the labor supply or labor demand equations, we find theequilibrium quantity of labor is 800:LS = (20)(40) = 800,andLD = 1,200 - (10)(40) = 800.Economic rent is the summation of the difference between the equilibrium wage andthe wage given by the labor supply curve. Here, it is the area above the labor supplycurve up to L = 800 and below the equilibrium wage. This triangle’s area is(0.5)(800)($40) = $16,000.9. This exercise is a continuation of Exercise 8. Suppose now that the only labor available is controlled by a monopolistic labor union that wishes to maximize the rent earned by union members. What will be the quantity of labor employed and the wage rate? How does your answer compare with your answer to Exercise 8? Discuss. (Hint: The union’s marginal revenue curve is given by L = 1200 - 20w.)Recall that the monopolist chooses output by setting marginal revenue equal to themarginal cost of supplying one more unit of output, asopposed to the competitive firmwhich chooses output by setting price equal to marginal cost, or in other wordsproducing where supply intersects demand. The monopolistic labor union acts in thesame way. To maximize rent in this case, the union will choose the number of workershired so that the marginal revenue to the union (the additional wages earned) is equalto the extra cost of inducing the worker to work. This involves choosing the quantity oflabor at the point where the marginal revenue curve crosses the supply curve of labor.Note that the marginal revenue curve has twice the slope of the labor demand curve.Marginal revenue is less than the wage, because when more workers are hired, allworkers receive a lower wage.Setting the marginal revenue curve equal to the supply curve for labor, we find:1200 - 20w = 20w, or w* = 30.At w*, we may determine the number of workers who are willing to work bysubstituting w* into the labor supply equation:L* = (20)(30) = 600.Therefore, if the union wants to maximize the rent that the union members earn, theunion should limit employment to 600 members.To determine the wage the members will earn, substitute L* into the labor demandequation:600 = 1,200 - 10w, or w = 60.The total rent the employed union members will receive is equal to:Rent = (60 - 30)(600) + (0.5)(30)(600) = $27,000.Notice that the wage is higher and the number of workers employed is lower than in Exercise (8).*10. A firm uses a single input, labor, to produce output q according to the production function q . The commodity sells for $150 per unit and the wage rate is $75 per hour.a. Find the profit-maximizing quantity of L.There are two (equivalent) methods of solving this problem.Most generally, definethe profit function, where revenues and costs are expressed in terms of the input,calculate the first order necessary condition (the first derivative of the profit function),and solve for the optimal quantity of the input. Alternatively, use the rule that the平狄克微观经济学第六版课后答案firm will hire labor up until the point where the marginal revenue product (p*MPL) equals the wage rate. Using the first method:TR TC pq wL150*8*L 75L1 600L2 75 0 LL 64.12b. Find the profit-maximizing quantity of q.From part a, the profit maximizing quantity of labor is 64 so substitute this quantity of labor into the production function to find q 8L 8* 64. 12c.d. What is the maximum profit? Profit is total revenue minustotal cost or 150*64 75*64 4800. Suppose now that the firm is taxed $30 per unit of output and the wage rate issubsidized at a rate of $15 per hour. Assume the firm is a price taker, so that the price of the product remains at $150. Find the new profit-maximizing levels of L, q, and profit.After the $30 tax per unit of output is paid, the firm receives 150-30=$120 per unit of output sold. This is the relevant price for the profit maximizing decision. The input cost is now 75-15=$60 per unit labor after the subsidy is received. The profit maximizing values can be found as in parts a-c above:TR TC pq wL120*8*L 60L1 480L2 60 0 LL 64q 64123840.e. Now suppose that the firm is required to pay a 20% tax on its profits. Find thenew profit-maximizing levels of L, q, and profit.The profit maximizing values can be found as in parts a-c above, only here profit is 80% of total revenue minus total cost.。
平狄克《微观经济学》课后答案 3-4
CHAPTER 3CONSUMER BEHAVIORChapter 3 builds the foundation to derive the demand curve in Chapter 4. In order to understand demand theory, students must have a firm grasp of indifference curves, the marginal rate of substitution, the budget line, and optimal consumer choice. Utility theory may be discussed independently from consumer choice. Many students find utility functions to be a more abstract concept than preference relationships. However, if you plan to discuss uncertainty in Chapter 5, you will need to cover marginal utility. Even if you cover utility theory only briefly, make sure students are comfortable with the term utility because it appears frequently in Chapter 4.When introducing indifference curves, stress that physical quantities are represented on the two axes. After discussing supply and demand, students may think that price should be on the vertical axis. To develop indifference curves, start with any point in the Cartesian plane and ask for points that are more (and less) preferred. This will divide the plane into four quadrants. Then ask between which points they will be indifferent. Once students grasp the concept of preference points, introduce the notion of a “preference hill.” Using the example of a topographical map or a well-drawn three dimensional figure, point out that a three-dimensional figure is being collapsed into two dimensions.The marginal rate of substitution, MRS , is confusing to students. Some confuse the MRS with the ratio of the two quantities. If this is the case, point out that the slope is equal to the ratio of the rise, ∆Y, and the run, ∆X . This ratio is equal to the ratio of the intercepts of a line just tangent to the indifference curve. As we move along a convex indifference curve, these intercepts and the MRS change. Another problem is the terminology “of X for Y .” This is confusing because we are not substituting “X for Y ,” but Y for one unit of X . Exercise (6) discusses this point, but you may want to offer other exercises to stress it.1. What does transitivity of preferences mean?Transitivity of preferences implies that if someone prefers A to B and prefers B to C , then he orshe prefers A to C .satisfaction. This trading continues until the highest level of satisfaction is achieved.6. Explain why consumers are likely to be worse off when a product that they consume is rationed.If the maximum quantity of a good is fixed by decree and desired quantities are not available forpurchase, then there is no guarantee that the highest level of satisfaction can be achieved. Theconsumer will not be able to give up the consumption of other goods in order to obtain more of therationed good. Only if the amount rationed is greater than the desired level of consumption canthe consumer still maximize satisfaction without constraint. (Note: rationing may imply ahigher level of social welfare because of equity or fairness considerations across consumers.)7. Upon merging with West Germany’s economy, East German consumers indicated a preference for Mercedes-Benz automobiles over Volkswagen automobiles. However, when they converted their savings into deutsche marks, they flocked to Volkswagen dealerships. How can you explain this apparent paradox?Three assumptions are required to address this question: 1) that a Mercedes costs more than aVolkswagen; 2) that the East German consumers’ utility function comprises two goods,automobiles and all other goods evaluated in deutsche marks; and 3) that East Germans haveincomes. Based on these assumptions, we can surmise that while once-East German consumersmay prefer a Mercedes to a Volkswagen, they either cannot afford a Mercedes or they prefer abundle of other goods plus a Volkswagen to a Mercedes alone.8. Describe the equal marginal principle. Explain why this principle may not hold if increasing marginal utility is associated with the consumption of one or both goods.The equal marginal principle states that the ratio of the marginal utility to price must be equalacross all goods to obtain maximum satisfaction. This explanation follows from the same logicexamined in Review Question 5. Utility maximization is achieved when the budget is allocatedso that the marginal utility per dollar of expenditure is the same for each good.If marginal utility is increasing, the consumer maximizes satisfaction by consuming ever largeramounts of the good. Thus, the consumer would spend all income on one good, assuming aconstant price, resulting in a corner solution. With a corner solution, the equal marginalprinciple cannot hold.9. What is the difference between ordinal utility and cardinal utility? Explain why the assumption of cardinal utility is not needed in order to rank consumer choices.Ordinal utility implies an ordering among alternatives without regard for intensity of preference.For example, the consumer’s first choice is preferred to their second choice. Cardinal utilityimplies that the intensity of preferences may be quantified. An ordinal ranking is all that isneeded to rank consumer choices. It is not necessary to know how intensely a consumer prefersbasket A over basket B; it is enough to know that A is preferred to B.10. The price of computers has fallen substantially over the past two decades. Use this drop in price to explain why the Consumer Price Index is likely to substantially understate the cost-of-living index for individuals who use computers intensively.The consumer price index measures the changes in the weighted average of the prices of thebundle of goods purchased by consumers. The weights equal the share of consumer's expenditureson all of the goods in the bundle. A base year is chosen, and the weights for that year are used tocompute the CPI in that and subsequent years. When the price of a good falls substantially then aconsumer will substitute towards that good, altering the share of that consumer's income spent oneach good. By using the base year's weights the CPI does not take into account that large pricechanges alter these expenditure shares, and so gives an inaccurate measure of changes in the costof living.For example, assume Fred spends 10% of his income on computers in 1970, and that Fred'sexpenditure shares in 1970 were used as the weights to calculate Fred's CPI in subsequent years.If Fred's demand for computers was inelastic, then reductions in the price of computers (relativeto other goods) would reduce the share of his income spent on computers. After 1970 a CPI thatused Fred's 1970 expenditure shares as weights would give a 10% weight to the falling price ofcomputers, even though Fred spent less that 10% of his income on computers. So long as theprices of other goods rose, or fell less than 10%, then the CPI gives too little weight to the changesin the prices of other goods, and understates the changes in Fred's cost of living.1. In this chapter, consumer preferences for various commodities did not change during the analysis. Yet in some situations, preferences do change as consumption occurs. Discuss why and how preferences might change over time with consumption of these two commodities:a. cigarettesThe assumption that preferences do not change is a reasonable one if choices are independentacross time. It does not hold, however, when “habit-forming” or addictive behavior is involved, asin the case of cigarettes: the consumption of cigarettes in one period influences their consumptionin the next period.b. dinner for the first time at a restaurant with a special cuisineWhile there may not be anything physically addictive in dining at new and different restaurants, one can become better informed about a particular restaurant. One may enjoy choosing more new and different restaurants, or one may be tired of choosing another new and different place to4.a.c. tothis graphically?, the quantity of butter by B, the Let Bill’s income be represented by Y, the price of butter by PB, and the quantity of margarine by M. Then the general form of the price of margarine by PMbudget constraint is:5.the their a.c. If both Smith and Jones pay the same prices for their refreshments, will their marginal rates ofsubstitution of alcoholic for nonalcoholic drinks be the same or different? Explain.In order to maximize utility, the consumer must consume quantities such that the MRS betweenany two commodities is equal to the ratio of prices. If Smith and Jones are rational consumers,their MRS must be equal because they face the same market prices. But because they havedifferent preferences, they will consume different amounts of the two goods, alcoholic andnonalcoholic. At those different levels, however, their MRS are equal.6. Anne is a frequent flyer whose fares are reduced (through coupon giveaways) by 25 percent after she flies 25,000 miles a year, and then by 50 percent after she flies 50,000 miles. Can you graph the budget line that Anne faces in making her flight plans for the year?In Figure 3.6, we plot miles flown, M , against all other goods, G , in dollars. The budgetconstraint is:Y = P M M + P G G , or.⎪⎪⎭⎫ ⎝⎛-=G M G P P M P Y G The slope of the budget line is -P P M G. In this case, the price of miles flown changes as the number of miles flown changes, so the budget curve is kinked at 25,000 and at 50,000 miles. Suppose P M is $1 per mile for less than or equal to 25,000 miles. Then P M = $0.75 for 25,000 < M ≥ 50,000 and P M = $0.50 for M > 50,000. Also, let P G = $1.00. Then the slope of the budget line from A to B is -1, the slope of the budget line from B to C is -0.75, and the slope of the budget line from B to D is -0.5.8. Suppose that Samantha and Jason both spend $24 per week on video and movie entertainment.U = 12 U = 24Food Clothing Food Clothing 1.0 12.0 1.0 24.01.5 8.02.0 12.02.0 6.03.0 8.012 = 1F + 3C , or ⎪⎪⎭⎝-=34.See Figure 3.10.a.c. What is the utility-maximizing choice of food and clothing? (Hint: Solve the problemgraphically.)The highest level of satisfaction occurs where the budget line is tangent to the highestindifference curve. In Figure 3.10.a this is at the point F = 6 and C = 2. To check this answer,note that it exhausts Jane’s income, 12 = 6P F + 2P C . Also, this bundle yields a satisfaction of 12,as (6)(2) = 12. See Figure 3.10.a.d. What is the marginal rate of substitution of food for clothing when utility is maximized?At the utility-maximizing level of consumption, the slope of the indifference curve is equal to theslope of the budget constraint. Since the MRS is equal to the negative slope of the indifferencecurve, the MRS in this problem is equal to one-third. Thus, Jane would be willing to give upone-third of a unit of clothing for one unit of food.e. Suppose that Jane buys 3 units of food and 3 units of clothing with her $12 budget. Would hermarginal rate of substitution of food for clothing be greater or less than 1/3? Explain.If Jane buys 3 units of food for $1.00 per unit and 3 units of clothing for $3.00 per unit, she wouldspend all her income. However, she would obtain a level of satisfaction of only 9, whichrepresents a sub-optimal choice. At this point, the MRS is greater than one-third, and thus, atthe prices she faces, she would welcome the opportunity to give up clothing to get more food. Sheis willing to trade clothing for food until her MRS is equal to the ratio of prices. See Figure3.10.c.Figure 3.10.c11. The utility that Meredith receives by consuming food F and clothing C is given by u(F,C) = FC. Suppose that Meredith’s income in 1990 is $1,200 and the prices of food and clothing are $1 per unit for each. However, by 1995 the price of food has increased to $2 and the price of clothing to $3. Let 100 represent the cost of living index for 1990. Calculate the ideal and the Laspeyres cost-of-living index for Meredith for 1995. (Hint: Meredith will spend equal amounts on food and clothing with these preferences.)Laspeyres IndexThe Laspeyres index represents how much more Meredith would have to spend in 1995 versus 1990 ifshe consumed the same amounts of food and clothing in 1995 as she did in 1990. That is, the Laspeyresindex for 1995 (L) is given by:L = 100 (Y ')/Ywhere Y’ represents the amount Meredith would spend at 1995 prices consuming the same amount offood and clothing as in 1990: Y ' = P 'F F + P 'C C = 2F + 3C, where F and C represent the amounts of foodand clothing consumed in 1990.We thus need to calculate F and C, which make up the bundle of food and clothing which maximizesMeredith’s utility given 1990 prices and her income in 1990. Use the hint to simplify the problem:Since she spends equal amounts on both goods, P F F = P C C. Or, you can derive this same equationmathematically: With this utility function, MU C = ∆U/∆C = F, and MU F = ∆U/∆F = C. To maximizeutility, Meredith chooses a consumption bundle such that MU F /MU C = P F /P C , which again yields P F F =P C C.From the budget constraint, we also know that:P F F +P C C = YCombining these two equations and substituting the values for the 1990 prices and income yields thesystem of equations:C = F and C + F = 1,200Solving these two equations, we find that:C = 600 and F = 600Therefore, the Laspeyres cost-of-living index is:L = 100(2F + 3C)/Y = 100[(2)(600) + (3)(600)]/1200 = 250Ideal IndexThe ideal index represents how much more Meredith would have to spend in 1995 versus 1990 if sheconsumed amounts of food and clothing in 1995 which would give her the same amount of utility as shehad in 1990. That is, the ideal index for 1995 (I) is given by:I = 100(Y'')/Y, where Y'' = P'F F + P'C C' = 2F' + 3C'where F' and C' are the amount of food and clothing which give Meredith the same utility as she had in1990. F' and C' must also be such that Meredith spends the least amount of money at 1995 prices toattain the 1990 utility level.The bundle (F',C') will be on the same indifference curve as (F,C) and the indifference curve at this point will be tangent to a budget line with slope -(P'F /P'C ), where P'F and P'C are the prices of food and clothing in 1995. Since Meredith spends equal amounts on the two goods, we know that 2F' = 3C'. Since this bundle lies on the same indifference curve as the bundle F = 600, C = 600, we also know that F'C' = (600)(600).Cslope 1P slope F C =-H K slope slope F C =-'H KFigure 3.11Solving for F' yields:F'[(2/3)F'] = 360,000 or F' =[(/),)]32360000 = 734.8From this, we obtain C':C' = (2/3)F' = (2/3)734.8 = 489.9We can now calculate the ideal index: I = 100(2F' + 3C')/Y = 100[2(734.8) + (3)(489.9)]/1200 = 244.9CHAPTER 4INDIVIDUAL AND MARKET DEMANDChapter 4 relies on two important ideas from Chapter 3: the influence of price and income changes on the budget line and optimal consumer choice. The chapter focuses on price changes, individual demand, market demand, demand elasticity, and consumer surplus. These concepts are crucial to understanding the application of demand and supply analysis in Chapter 9 as well as the discussion of market failure in Parts III and IV. Chapter 4 also discusses the derivation of the individual’s demand curve with a discussion of substitution and income effects. The analytical tools students learn in this chapter will be important for the discussion of factor supply and demand in Chapter 14.When discussing the derivation of demand, review how the budget curve pivots around an intercept as price changes and how optimal quantities change as the budget line pivots. Once students understand the effect of price changes on consumer choice, they can grasp the derivation of the price consumption path and the individual demand curve. Remind students that the price a consumer is willing to pay is a measure of the marginal benefit of consuming another unit.When covering the aggregation of individual demands, stress that this is equivalent to the summation of individual demand curves horizontally. Students might think that they can add linear demand functions, e.g., add Q P =-1 plus Q P =-23 to arrive at Q P =-35 or 223Q P =-. Students must be reminded, instead, to write the demand curve in inverse form, with price as a function of quantity, and then add. Thus, we add P = 1 - Q to P = 1 - 2Q to obtain P = 2 - 3Q .Price elasticity of demand and consumer surplus are referred to throughout the text, but the mathematics of price elasticity of demand is difficult for many students. Before discussing the algebra, encourage students to develop an intuitive grasp of elasticity as a measure of the sensitivity of the quantity demanded to changes in price.The easiest algebraic representation of elasticity is %%∆∆QP. As you expand on this expression, make sure thatstudents can distinguish between the slope of a line and an elasticity at each point. One effective teaching method is using a linear demand curve to show that while the slope is constant, the elasticity changes throughout the range of prices. The text relies on this relationship in the discussion of the monopolist’s determination of the profit-maximizing quantity in Chapter 10. The exercises given here are progressive in their difficulty, i.e., the last exercise is much harder than the first. Exercises (1) and (7) assume student understanding of demand elasticity, and a grasp of income elasticity is needed for Exercise (9).Although this chapter introduces consumer surplus, it is not extensively discussed until Chapter 9; producer surplus is covered in Chapter 8. If you postpone the discussion of consumer surplus, do not assign Exercise (4). Once students understand consumer surplus, they will find it to be an extremely useful tool. See Example 4.5.Section 4.2 discusses income and substitution effects. An understanding of these effects is aided by the discussion of normal and inferior goods. This is also a good time to reinforce the concept of relative prices, i.e., a decrease in the price of one good increases the relative price of the other good. Giffen goods, while infrequently encountered, provide a way to discuss the importance of income and substitution effects.Finally, there are other special topics in this chapter and its Appendix. An application of network externalities is given in Example 4.5. The first part of Section 4.6, “Empirical Estimation of Demand,” is straightforward, particularly if you have covered the forecasting section of Chapter 2. However, the l ast part, “The Form of the Demand Relationship,” is difficult for students who do not understand logarithms. The Appendix is intended for students with a background in calculus.1.How is an individual demand curve different from a market demand curve? Which curve is likely to be more price elastic? (Hint: Assume that there are no network externalities.)The market demand curve is the horizontal summation of the individual demand curves. Thegraph of market demand shows the relation between each price and the sum of individualquantities. Because price elasticities of demand may vary by individual, the price elasticity ofdemand is likely to be greater than some individual price elasticities and less than others.2.Is the demand for a particular brand of product, such as Head skis, likely to be more price elastic or price inelastic than the demand for the aggregate of all brands, such as downhill skis? Explain.Individual brands compete with other brands. If the two brands are similar, a small change inthe price of one good will encourage many consumers to switch to the other brand. Becausesubstitutes are readily available, the quantity response to a change in one brand’s price is moreelastic than the quantity response for all brands. Thus, the demand for Head skis is more elasticthan the demand for downhill skis.3.Tickets to a rock concert sell for $10. But at that price, the demand is substantially greater than the available number of tickets. Is the value or marginal benefit of an additional ticket greater than, less than, or equal to $10? How might you determine that value?If, at $10, demand exceeds supply, then consumers are willing to bid up the market price to a levelwhere the quantity demanded is equal to the quantity supplied. Since utility-maximizingconsumers must be willing to pay more than $10, then the marginal increase in satisfaction(value) is greater than $10. One way to determine the value of tickets would be to auction off ablock of tickets. The highest bid would determine the value of the tickets.4.Suppose a person allocates a given budget between two goods, food and clothing. If food is an inferior good, can you tell whether clothing is inferior or normal? Explain.If an individual consumes only food and clothing, then any increase in income must be spent oneither food or clothing (Hint: we assume there are no savings). If food is an inferior good, then,as income increases, consumption falls. With constant prices, the extra income not spent on foodmust be spent on clothing. Therefore, as income increases, more is spent on clothing, i.e. clothingis a normal good.5. Which of the following combinations of goods are complements and which are substitutes? Could they be either in different circumstances? Discuss.a. a mathematics class and an economics classIf the math class and the economics class do not conflict in scheduling, then the classes could beeither complements or substitutes. The math class may illuminate economics, and theeconomics class can motivate mathematics. If the classes conflict, they are substitutes.b. tennis balls and a tennis racketTennis balls and a tennis racket are both needed to play a game of tennis, thus they arecomplements.c. steak and lobsterFoods can both complement and substitute for each other. Steak and lobster can compete, i.e., besubstitutes, when they are listed as separate items on a menu. However, they can also functionas complements because they are often served together.d. a plane trip and a train trip to the same destinationTwo modes of transportation between the same two points are substitutes for one another.e. bacon and eggsBacon and eggs are often eaten together and are, therefore, complementary goods. Byconsidering them in relation to something else, such as pancakes, bacon and eggs can function assubstitutes.6.Which of the following events would cause a movement along the demand curve for U.S.-produced clothing, and which would cause a shift in the demand curve?a. the removal of quotas on the importation of foreign clothesThe removal of quotas will shift the demand curve inward for domestically-produced clothes,because foreign-produced goods are substitutes for domestically-produced goods. Both theequilibrium price and quantity will fall as foreign clothes are traded in a free marketenvironment.b. an increase in the income of U.S. citizensWhen income rises, expenditures on normal goods such as clothing increase, causing the demandcurve to shift out. The equilibrium quantity and price will increase.c. a cut in the industry’s costs of producing domestic clothes that is passed on to the market inthe form of lower clothing pricesA cut in an industry’s costs will shift the supply curve out. The equilibrium price an d quantitywill increase.7. For which of the following goods is a price increase likely to lead to a substantial income (as well as substitution) effect?a. saltSmall income effect, small substitution effect: The amount of income that is spent on salt isrelatively small, but since there are few substitutes for salt, consumers will not readily substituteaway from it. As the price of salt rises, real income will fall only slightly, thus leading to a smalldecline in consumption.b. housingLarge income effect, no substitution effect: The amount of income spent on housing is relativelylarge for most consumers. If the price of housing were to rise, real income would be reducedsubstantially, thereby reducing the consumption of all other goods. However, consumers wouldfind it impossible to substitute for housing, in general.c. theater ticketsSmall income effect, large substitution effect: The amount of income that is spent on theatertickets is relatively small, but consumers can substitute away from the theater tickets by choosingother forms of entertainment (e.g., television and movies). As the price of theater tickets rises,real income will fall only slightly, thus leading to a small decline in consumption.d. foodLarge income effect, no substitution effect: As with housing, the amount of income spent on food isrelatively large for most consumers. Price increases for food will reduce real incomesubstantially, thereby reducing the consumption of all other commodities. Although consumerscan substitute out of particular foods, they cannot substitute out of food in general.8. Suppose that the average household in a state consumes 500 gallons of gasoline per year. A 10-cent gasoline tax is introduced, coupled with a $50 annual tax rebate per household. Will the household be better or worse off after the new program is introduced?If the household does not change its consumption of gasoline, it will be unaffected by thetax-rebate program. It still gets 500 gallons of gasoline. To the extent that the householdreduces its gas consumption through substitution, it must be better off.9. Which of the following three groups is likely to have the most, and which the least, price-elastic demand for membership in the Association of Business Economists?a. studentsThe major difference among the groups is the level of income. We know that if the consumptionof a good constitutes a large percentage of an individual’s income, then the demand for the goodwill be relatively elastic. If we assume that a membership in the Association of BusinessEconomists is likely to be a large expenditure for students, we may conclude that the demand willbe relatively elastic for this group.b. junior executivesThe level of income for junior executives will be larger than that of students, but smaller thanthat of senior executives. Therefore, the demand for a membership for this group will be lesselastic than that of the students but more elastic than that of the senior executives.c. senior executivesThe high earnings among senior executives will result in a relatively inelastic demand formembership.1. The ACME corporation determines that at current prices the demand for its computer chips has a price elasticity of -2 in the short run, while the price elasticity for its disk drives is -1.a. If the corporation decides to raise the price of both products by 10 percent, what will happento its sales? To its sales revenue?We know the formula for the elasticity of demand is:EQP P=%%∆∆.For computer chips, EP= -2, so a 10 percent increase in price will reduce the quantity sold by 20percent. For disk drives, EP= -1, so a 10 percent increase in price will reduce sales by 10 percent.Sales revenue is equal to price times quantity sold. Let TR1 = P1Q1be revenue before the pricechange and TR2 = P2Q2be revenue after the price change.For computer chips:∆TR cc = P2Q2 - P1Q1∆TR cc= (1.1P1 )(0.8Q1 ) - P1Q1 = -0.12P1Q1, or a 12 percent decline.For disk drives:∆TR dd = P2Q2 - P1Q1∆TR dd = (1.1P1 )(0.9Q1 ) - P1Q1 = -0.01P1Q1, or a 1 percent decline.Therefore, sales revenue from computer chips decreases substantially, -12 percent, while the salesrevenue from disk drives is almost unchanged, -1 percent.b. Can you tell from the available information which product will generate the most revenue forthe firm? If yes, why? If not, what additional information would you need?No. Although we know the responsiveness of demand to changes in price, we need to know bothquantities and prices of the products to determine total sales revenue.2. Refer to Example 4.3 on the aggregate demand for wheat. From 1981 to 1990, domestic demand grew in response to growth in U.S. income levels. As a rough approximation, the domestic demand curve in 1990 was QDD= 1200 - 55P. Export demand, however, remained about the same, due to。
最新平狄克微观经济学答案第12-13章
平狄克微观经济学答案第12-13章第12章垄断竞争和寡头垄断复习题1.答:垄断竞争主要有以下几个特征:第一,集团中,有大量的企业生产有差别的同种产品,这些产品彼此之间是非常接近的替代品。
第二,一个生产集团中的企业数量非常多,以至于每个厂商都以为自己的行为的影响很小,不会引起竞争对手的注意和反应,因而自己也不会受到对手的任何报复措施的影响。
第三,厂商的生产规模不大,因此,进入和退出一个生产集团比较容易。
如果一个厂商推出了新型、改进型的产品,会使得该市场上每个厂商的需求曲线向内平移,导致每个企业的均衡价格和数量减少。
2.因为在垄断市场中,产品之间是非常接近的替代品,因而对某个品牌商品的需求弹性很大,所以厂商的向右下倾斜的需求曲线是比较平坦的,相对地比较接近完全竞争厂商的需求曲线的形状。
而市场需求曲线表示的是消费者对某个生产集团所生产的一类产品的总的需求状况,这类产品对于消费者来说是必须的,替代品很少甚至没有,其需求曲线显然小于消费者对此类产品中不同品牌产品的需求弹性,因此市场需求曲线要较单个厂商的需求曲线陡峭。
由于生产集团内部某个厂商存在着利润,新的厂商就会被吸引进来。
当他们推出竞争性品牌时,在市场需求规模不变的条件下,这个厂商将会损失一部分市场分额,需求曲线、边际收益曲线向内平移,直至利润消失为止。
3.支持的观点:你在家乐福和沃尔玛可以看到种类繁多的各种麦片,比如黑牛提包高钙营养麦片、金味全味即溶麦片、皇室麦片、皇室营养麦片、雀剿营养麦片、雀剿中老年麦片、雅什利营养麦片……在麦片这种产品上生产了如此多的派品,占用了很多经济资源,表明这个行业中,生产能力过剩了。
反对的观点:消费者的需求是多种多样的,消费者有权从广泛的商品中选择自己喜欢的产品。
而品牌多样性也有助于刺激需求。
4.在古诺均衡中,每个寡头的产量都是在给定它的竞争对手的产量时它所能实现的利润最大化的产量(有理由相信,在古诺模型中,在均衡点上,各寡头对于自己的产量的预期是正确的),此时,双方都处在了给定竞争对手的条件下,自己所能做的最好的行为。
平狄克《微观经济学》(第9版)笔记和课后习题详解
平狄克《微观经济学》(第9版)笔记和课后习题详解
来源微♥公号精研学习网
第1篇导论:市场与价格
第1章绪论
1.1复习笔记
【知识框架】
【考点难点归纳】
考点一:微观经济学的主题(见表1-1)★
表1-1微观经济学的主题
考点二:微观经济学的分析方法——实证分析和规范分析(见表1-2)★★
表1-2微观经济学的分析方法——实证分析和规范分析
考点三:市场★
市场是指买者和卖者的集合,以及由此确定的潜在的买卖。
微观经济学中的市场不仅有买方和卖方都不会影响市场的竞争性市场,还有卖方影响市场的非竞争市场,如寡头市场、垄断竞争市场等。
市场是有范围的,不仅要考虑地理边界,还要考虑包含产品范围的大小。
如住房市场是高度当地化的,而黄金市场却是世界性的。
市场的价格是在买卖双方互动的基础上形成的。
一般而言,微观经济学考察市场均衡的价格,即一个市场上的供给等于需求时的价格。
考点四:名义价格与实际价格★★
1名义价格与实际价格的含义
名义价格是指以某些货币表示的,未经过通货膨胀的调整的价格。
实际价格则是指名义价格剔除通货膨胀因素之后的价格。
2名义价格与实际价格的关系
名义价格与实际价格的关系需要引入消费价格指数(CPI)。
居民消费价格指数是一个反映居民家庭一般所购买的消费品和服务项目价格水平变动情况的宏观经济指标,它是衡量通货膨胀的主要指标之一。
某年商品的实际价格与名义价格之间的关系为:
某年商品的实际价格=基准年消费物价指数/计算年消费物价指数×计算年的名义价格。
(NEW)平狄克《微观经济学》(第7版)课后习题详解
目 录第1篇 导论:市场和价格第1章 绪 论1.1 课后复习题详解1.2 课后练习题详解第2章 供给和需求的基本原理2.1 课后复习题详解2.2 课后练习题详解第2篇 生产者、消费者以及竞争性市场第3章 消费者行为3.1 课后复习题详解3.2 课后练习题详解第4章 个人需求和市场需求4.1 课后复习题详解4.2 课后练习题详解第4章附录 需求理论——一种数学的处理方法课后练习题详解第5章 不确定性与消费者行为5.1 课后复习题详解5.2 课后练习题详解第6章 生 产6.1 课后复习题详解6.2 课后练习题详解第7章 生产成本7.1 课后复习题详解7.2 课后练习题详解第7章附录 生产与成本理论——一种数学的处理方法课后练习题详解第8章 利润最大化和竞争性供给8.1 课后复习题详解8.2 课后练习题详解第9章 竞争性市场分析9.1 课后复习题详解9.2 课后练习题详解第3篇 市场结构和竞争策略第10章 市场势力:垄断与买方垄断10.1 课后复习题详解10.2 课后练习题详解第11章 有市场势力的定价11.1 课后复习题详解11.2 课后练习题详解第11章附录 联合厂商的内部转移定价课后练习题详解第12章 垄断竞争和寡头垄断12.1 课后复习题详解12.2 课后练习题详解第13章 博弈论和竞争策略13.1 课后复习题详解13.2 课后练习题详解第14章 投入要素市场14.1 课后复习题详解14.2 课后练习题详解第15章 投资、时间及资本市场15.1 课后复习题详解15.2 课后练习题详解第4篇 信息、市场失灵以及政府的角色第16章 一般均衡与经济效率16.1 课后复习题详解16.2 课后练习题详解第17章 信息不对称市场17.1 课后复习题详解17.2 课后练习题详解第18章 外部性与公共品18.1 课后复习题详解18.2 课后练习题详解附录:指定平狄克《微观经济学》教材为考研参考书目的院校列表第1篇 导论:市场和价格第1章 绪 论1.1 课后复习题详解1.人们常说,一个好的理论是可以用经验研究和实证研究来加以证伪的。
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平狄克微观经济学课后习题答案(中文)第一章复习题1.市场是通过相互作用决定一种或一系列产品价格的买卖双方的集合,因此可以把市场看作决定价格的场所。
行业是出售相同的或紧密相关的产品的厂商的集合,一个市场可以包括许多行业。
2.评价一个理论有两个步骤:首先,需要检验这个理论假设的合理性;第二,把该理论的预测和事实相比较以此来验证它。
如果一个理论无法被检验的话,它将不会被接受。
因此,它对我们理解现实情况没有任何帮助。
3.实证分析解释“是什么”的问题,而规范分析解释的是“应该是什么”的问题。
对供给的限制将改变市场的均衡。
A中包括两种分析,批评这是一种“失败的政策”——是规范分析,批评其破坏了市场的竞争性——是实证分析。
B向我们说明在燃油的配给制下总社会福利的被损坏——是实证分析。
4.由于两个市场在空间上是分离的,商品在两地间的运输是套利实现的条件。
如果运输成本为零,则可以在Oklahoma购买汽油,到New Jersey出售,赚取差价;如果这个差价无法弥补运输成本则不存在套利机会。
5.商品和服务的数量与价格由供求关系决定。
鸡蛋的实际价格从1970年至1985年的下降,一方面是由于人们健康意识的提高而导致鸡蛋需求的减少,同时也因为生产成本的降低。
在这两种因素下,鸡蛋的价格下降了。
大学教育的实际价格的升高,是由于越来越多的人倾向于获得大学教育而导致需求提高,同时教育的成本也在升高。
在这两方面因素作用下,大学教育费用提高了。
6.日圆相对美圆来说,价值升高,升值前相比,兑换同样数量的日圆需要付出更多的美圆。
由汇率的变化引起购买力的变化,在日本市场出售的美国汽车,由于美圆贬值日圆升值,持有日圆的消费者将较以前支付较底的价格;而在美国市场出售的日本汽车,由于日圆升值美圆贬值,持有美圆的消费者将面对较以前提高的价格。
4.长期弹性和短期弹性区别在于消费者对价格变化的反映速度以及可获得的替代品。
对纸巾这样的非耐用品,价格上升,消费者在短期内的反映很小。
但在长期,对纸巾的需求将会变得富有弹性。
对于象电视机这样的耐用消费品,在短期内,价格的变动可能会引起需求的剧烈变化,价格的上升可能会使消费者推迟购买。
因此耐用品的需求在长期是富有弹性的。
5. 供给价格弹性是供给量变动的百分比和价格变动百分比的比值。
价格上升将引起供给的增加。
有些厂商在短期内,由于生产能力的限制无法迅速增加产量。
这样,在短期内,供给是缺乏弹性的。
然而在长期情况下,厂商可以调整生产规模,因而,从长期来看,供给是富有弹性的。
6. 如果商品价格被定在市场出清水平以下,厂商愿意提供的产量则低于消费者希望购买的数量。
短缺的程度则取决于供求的相对弹性。
供求均富有弹性情况下的缺口要大于双方缺乏弹性时的情况。
消费者无法在价格管制的情况下购买到他想购买到的数量。
他将去购买替代品,这样,替代品的价格会上升。
牛肉和鸡肉的价格被管制后,猪肉的价格将上升。
7. 如果需求固定,单个厂商(大学)可以通过升高价格来决定需求曲线的形状。
大学官员没在过去的15 年观察整个需求曲线,只是看到了均衡价格和数量。
如果供给曲线随需求曲线向上移动,需求是缺乏弹性的。
需求曲线之所以可以向上移动,是因为大学教育的价值提升,学生愿意为此支付高额学费。
d.苹果采摘着的增加将使苹果生产成本下降,供给增加,均衡价格下降,销售量上升。
e.供给曲线将外移,均衡价格下降,销售量上升。
练习题1.a.EQQPPPQQP DDDDD ==∆∆∆∆.P = 80,E d=–0.4 P = 100, E d=–0.56 b.EQQPPPQQP SSSSS ==∆∆∆∆.P = 80, E s=0.5.P = 100, E s=0.56c.均衡价格和数量为$100 ,18 million.d.价格定在80$,需求为20 million.,供给为16 million.,相差4 million.2.Q S = 1,800 + 240PQ D = 2,580 - 194P.'QD= (2,580 - 194P) + 200 = 2,780 - 194P1,800 + 240P = 2,780 - 194P, or434P = 980, or P* = $2.26 per bushel.Q S = 1,800 + (240)(2.26) = 2,342Q D = 2,780 - (194)(2.26) = 2,342.3.a.100 - 5P = 50 + 5P, P = $500.Q D = 100 - (5)(5) = 75Q S = 50 + (5)(5) = 75.租金在500美金时,750,000公寓可以被租掉。
当租金被控制在100美金时,供给量将达到550,000 (Q S = 50 + (5)(100) = 550),比管制前减少了200,000。
假设每个公寓可容纳一个三口之家,将有600,000离开城市。
Appartments (10,000抯)$1,000Rent 10020030040050060070080090020406080100ExcessDemand DemandSupplyFigure 2.3b.当租金达到900美金时,公寓的供给为50 + 5(9) = 95,or 950,000这将超过均衡水平200,000。
因此(0.5)(200,000) = 100,000 个公寓被新建。
但是需求仅仅为550,000。
4. a.由总需求 Q = 3,550 - 266P , 国内需求, Q d = 1,000 - 46P , ,得到出口需求Q e = 2,550 - 220P . 均衡价格:3,550 - 266P - 1,800 + 240P , orP = $3.46.需求减少40%,因此总需求Q D = Q d + 0.6Q e = 1,000 - 46P + (0.6)(2,550 - 220P ) = 2,530 - 178P . 均衡价格1,800 + 240P = 2,530 - 178P , orP = $1.75,在这一价格,市场出清量为2,219 million bushels ,总收益从$9.1 billion 降至 $3.9 billion.这将令大部分农民痛苦。
b.3美金的价格下市场并不在均衡状态,Demand = 1000 - 46(3) = 862. Supply = 1800 + 240(3) = 2,520, 超额供给 2,520 - 862 = 1,658.政府必须购买这个多余产量来支持价格,花费$3(1.66 million) = $5.0 billion 每年。
5. a.Q D = a - bP . E b P Q D =-F H G I KJ **. E D= -0.4 (长期价格弹性), P* = 0.75 (均衡价格),Q* = 7.5 (均衡产量).-=-F H I K 0407575...b, or b = 4. 7.5 = a - (4)(0.75), or a = 10.5.Q D = 10.5 - 4P .b.)需求下降20%:'Q D =-=-0810548432....a fa fP P .8.4 - 3.2P = -4.5 + 16P , orP = 0.672.6. a.D = 24.08 - 0.06P S C = 11.74 + 0.07P .在没有OPEC 组织下的供给S c = Q * = 13.E S = 0.10 , P * = $18, E S = d (P */Q *) , d = 0.07. 代入 d , S c , , P , c = 11.74 and S c = 11.74 + 0.07P .同样的, 因为 Q D = 23, E D = -b (P */Q *) = -0.05, b = 0.06. 代入 b , Q D = 23, , P = 18 23 = a - 0.06(18), a = 24.08. 因此 Q D = 24.08 - 0.06P .b.D = 32.18 - 0.51PS C = 7.78 + 0.29P.如上, E S = 0.4 ,E D = -0.4: E S = d(P*/Q*) ,E D = -b(P*/Q*), 0.4 = d(18/13) and -0.4 = -b(18/23).所以d = 0.29 ,b = 0.51.S c = c + dP,Q D = a - bP,13 = c + (0.29)(18) ,23 = a - (0.51)(18).So c = 7.78 ,a = 32.18.c.减产60亿桶后:S c' = 4 + S c = 11.74 + 4 + 0.07P = 15.74 + 0.07P,S" = 4 + S c = 11.78 + 0.29P.15.74 + 0.07P = 24.08 - 0.06P,短期中,P = $64.15;11.78 + 0.29P = 32.18 - 0.51P,长期中,P = $24.297.a.供给: Q = 14 + 2P G + 0.25P O需求: Q = -5P G + 3.75P O需求交叉弹性为:EQPPQGOGOGG=FH GIK JFH GIK J∆∆.设需求函数为:Q G = a - bP G + eP O(收入为常量), 则∆∆QPGOFH GIK J= e. 将它代入交叉弹性公式, E e P QPOOG=FH GIK J**, P O*andQ G*是均衡价格和产量. 我们知道P O*= $8 ,Q G*= 20 百万立方英尺(Tcf). 解得e,158 20.=FH GIK Je, e = 3.75.同样得, 供给方程可表示为:Q G = c + dP G + gP O,交叉价格弹性为 g P Q OG**F H G IK J , e= 0.1. ⎪⎭⎫ ⎝⎛=2081.0g , g = 0.25. E S = 0.2, P* = 2, Q* = 20. 因此⎪⎭⎫ ⎝⎛=2022.0d , d = 2. 同样, E D = -0.5, 所以⎪⎭⎫ ⎝⎛=-2025.0b , b = -5. 将d, g, b , , e 代入供给,需求方程,解得:20 = c + (2)(2) + (0.25)(8), c = 14,20 = a - (5)(2) + (3.75)(8), a = 0.如果油价为$8.00,意味着天然气价格为$2.00。
将油价代入供求方程,得到天然气价格14 + 2P G + (0.25)(8) = -5P G + (3.75)(8), 7P G = 14, orP G = $2.00.b.需求: Q D = (-5)(1.50) + (3.75)(8) = 22.5,供给: Q S = 14 + (2)(1.5) + (0.25)(8) = 19.在这种情况下将出现超额需求3.5 Tcf.c.需求: Q D = -5P G + (3.75)(16) = 60 - 5P G ,供给: Q S = 14 + 2P G + (0.25)(16) = 18 + 2P G .18 + 2P G = 60 - 5P G , ,P G = $6.第三章复习题1、偏好的可传递性是指:如果消费者在市场篮子A和B中更偏好A,在B和C中更偏好B,那么消费者A和C中更偏好A。