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八版课后答案电子版
内容简介知择学习网平狄克微观经济学第八版课后习题答案电子版，具有众多功能。
一，使用方便，便于查找，有时候资源太多，查找起来很麻烦，而且还没有书签功能，使用上多有不便。
二、可以在线做标记，做标注，这样一边看一遍做笔记可以节省时间。
三、我们的资料是实时更新的。
我们的资料分为两块内容：第一个就是复习笔记。
对本章的重难点都进行了整理，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了整理，可以说几乎浓缩了经典教材的知识精华，复习的时候使用它可以节省大量时间。
第二块课后答案。
参考大量经济学相关资料对平狄克微观经济学第8版课章后习题进行了详细的分析和解答，并对相关重要知识点进行了延伸和归纳。
巩固所学的知识点。
资料内容1. 2 课后复习题详解1. 人们常说，一个好的理论是可以用实证的、数据导向的研究来加以证伪的。
试解释为什么一个不能用经验事实来验证的理论不是一个好理论。
答：理论指对事物的合理解释和预测，对客观事物本质及其运动规律的科学认识，是关于应该做什么的规定和建议。
它既是实践的总结，又是实践的向导。
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。
一个好的理论在原则上可以用经验的、注重数据的研究来加以验证，经得起经验和实践的检验。
如果一个理论无法被检验的话，它将不会被接受，因为它对理解现实情况没有任何帮助。
所以，一个不能用经验事实来验证的理论不是一个好的理论。
2. 下面两个陈述哪个是实证分析，哪个是规范分析？这两类分析有什么不同？(1) 汽油配给制（为个人每年可购买的汽油量设置一个最大限额）是一个糟糕的社会政策，因为它阻碍了竟争性市场体系的运转。
(2) 由于汽油配给制而境况变差的人要多于因此而境况变好的人。
答：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，其中不包含任何的价值判断。
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.。