經(jīng)濟學(xué)原理第七版第10章外部性課件

1、Externalities 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.1ExternalitiesGovernment act

2、ion can sometimes improve upon market outcomesWhy markets sometimes fail to allocate resources efficientlyHow government policies can potentially improve the markets allocationWhat kinds of policies are likely to work best 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or du

3、plicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.2ExternalitiesExternalityThe uncompensated impact of one persons actions on the well-being of a bystanderMarket failure

4、 Negative externalityImpact on the bystander is adversePositive externalityImpact on the bystander is beneficial 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or

5、service or otherwise on a password-protected website for classroom use.3ExternalitiesNegative externalitiesExhaust from automobilesBarking dogsPositive externalitiesRestored historic buildingsResearch into new technologies 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or du

6、plicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.4Externalities and Market InefficiencyWelfare economics: a recapDemand curve: value to consumersPrices they are willing

7、 to paySupply curve: cost to suppliersEquilibrium quantity and priceEfficientMaximizes the sum of producer and consumer surplus 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a cert

8、ain product or service or otherwise on a password-protected website for classroom use.5Figure 16 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or other

9、wise on a password-protected website for classroom use.The Market for AluminumPrice ofAluminumQuantity of Aluminum0Demand(private value)Supply(private cost)The demand curve reflects the value to buyers, and the supply curve reflects the costs of sellers. The equilibrium quantity, QMARKET, maximizes

10、the total value to buyers minus the total costs of sellers. In the absence of externalities, therefore, the market equilibrium is efficient.QMARKETEquilibriumExternalities and Market InefficiencyNegative externalitiesCost to society (of producing a good)Larger than the cost to the good producers 201

11、5 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.7“All I can say is that if being a leading ma

12、nufacturer means being a leading polluter, so be it.”Externalities and Market InefficiencyNegative externalitiesSocial costPrivate costs of the producers (supply)Plus the costs to those bystanders affected adversely by the negative externalitySocial cost curve is above the supply curveTakes into acc

13、ount the external costs imposed on society 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use

14、.8Figure 29 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.Pollution and the Social Optim

15、umPrice ofAluminumQuantity of Aluminum0Demand(private value)Supply(private cost)In the presence of a negative externality, such as pollution, the social cost of the good exceeds the private cost. The optimal quantity, QOPTIMUM, is therefore smaller than the equilibrium quantity, QMARKET.QMARKETOptim

16、umSocial cost (private costand external cost)External Cost QOPTIMUMEquilibriumExternalities and Market InefficiencyNegative externalitiesOptimum quantity producedMaximize total welfareSmaller than market equilibrium quantityGovernment correct market failureInternalizing the externalityAltering incen

17、tives so that people take account of the external effects of their actions 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-pro

18、tected website for classroom use.10Externalities and Market InefficiencyPositive externalitiesEducationBenefit of education is privateExternalities: better government, lower crime rates, higher productivity and wagesSocial value is greater than private valueSocial value curveAbove the demand curve 2

19、015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.11Figure 312 2015 Cengage Learning. All Rig

20、hts Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.Education and the Social OptimumPrice ofEducationQuantity of Education0D

21、emand (private value)Supply(private cost)In the presence of a positive externality, the social value of the good exceeds the private value. The optimal quantity, QOPTIMUM, is therefore larger than the equilibrium quantity, QMARKET.QMARKETEquilibriumSocial value (privatevalue and external benefit)Ext

22、ernal BenefitQOPTIMUMOptimumExternalities and Market InefficiencyPositive externalitiesSocially optimal quantity is greater than market equilibrium quantityGovernment correct market failureInternalize the externalitySubsidy 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or d

23、uplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.13Externalities and Market InefficiencyNegative externalitiesMarkets produce a larger quantity than is socially desira

24、bleGovernment: taxPositive externalitiesMarkets produce a smaller quantity than is socially desirableGovernment: subsidy 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain pro

25、duct or service or otherwise on a password-protected website for classroom use.14Technology spillovers, industrial policy, and patent protectionTechnology spillover = Positive externalityImpact of one firms research and production efforts on other firms access to technological advanceGovernment: int

26、ernalize the externalitySubsidy = value of the technology spillover15 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protecte

27、d website for classroom use.Technology spillovers, industrial policy, and patent protectionIndustrial policyGovernment intervention in the economy that aims to promote technology-enhancing industriesPatent lawProtect the rights of inventors by giving them exclusive use of their inventions for a peri

28、od of time16 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.Public Policies Toward Extern

29、alitiesCommand-and-control policiesRegulate behavior directlyRegulation Market-based policies Provide incentives so that private decision makers will choose to solve the problem on their ownCorrective taxes and subsidiesTradable pollution permits 2015 Cengage Learning. All Rights Reserved. May not b

30、e copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.17Public Policies Toward ExternalitiesRegulation Regulate behavior directly: making certain beh

31、aviors either required or forbiddenCannot eradicate pollutionEnvironmental Protection Agency (EPA)Develop and enforce regulationsDictates maximum level of pollution Requires that firms adopt a particular technology to reduce emissions 2015 Cengage Learning. All Rights Reserved. May not be copied, sc

32、anned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.18Public Policies Toward ExternalitiesCorrective taxes and subsidiesCorrective taxes (Pigovian taxes)Induce

33、 private decision makers to take account of the social costs that arise from a negative externalityPlaces a price on the right to polluteReduce pollution at a lower cost to societyRaise revenue for the governmentEnhance economic efficiency 2015 Cengage Learning. All Rights Reserved. May not be copie

34、d, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.19Why is gasoline taxed so heavily?Negative externalities associated with drivingCongestion, accidents

35、, pollution20 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.Why is gasoline taxed so hea

36、vily?The gas tax = corrective taxDoesnt cause deadweight lossesMakes the economy work betterLess traffic congestionSafer roadsCleaner environment21 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license dis

37、tributed with a certain product or service or otherwise on a password-protected website for classroom use.Why is gasoline taxed so heavily?How high should the tax on gasoline be?Most European countriesHigher gasoline tax than in the U.S. 2007, Journal of Economic LiteratureOptimal corrective tax on

38、gasoline$2.28 per gallon in 2005 dollars$2.70 per gallon in 2012 dollarsActual tax in the U.S. in 2012:50 cents per gallon22 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain

39、 product or service or otherwise on a password-protected website for classroom use.Why is gasoline taxed so heavily?Tax revenue from a gasoline taxUsed to lower taxes that distort incentives and cause deadweight lossesSome government regulationsProduction of fuel-efficient cars unnecessary23 2015 Ce

40、ngage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.Public Policies Toward ExternalitiesTradable poll

41、ution permitsVoluntary transfer of the right to pollute from one firm to anotherNew scarce resource: pollution permitsMarket to trade permitsFirms willingness to payDepend on its cost of reducing pollution 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whol

42、e or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.24Public Policies Toward ExternalitiesAdvantage of free market for pollution permitsInitial allocation of pollution permits doesnt matte

43、rIf firms can reduce pollution at a low cost:Sell whatever permits they getIf firms can reduce pollution only at a high cost: buy whatever permits they needEfficient final allocation 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except fo

44、r use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.25Public Policies Toward ExternalitiesReducing pollution using pollution permits or corrective taxesFirms pay for their pollutionCorrective taxes: pay to the g

45、overnmentPollution permits: pay to buy permitsInternalize the externality of pollution 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a

46、password-protected website for classroom use.26Figure 427 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website fo

47、r classroom use.The Equivalence of Corrective Taxes and Pollution PermitsPrice ofpollutionIn panel (a), the EPA sets a price on pollution by levying a corrective tax, and the demand curve determines the quantity of pollution. In panel (b), the EPA limits the quantity of pollution by limiting the num

48、ber of pollution permits, and the demand curve determines the price of pollution. The price and quantity of pollution are the same in the two cases.0Quantity ofpollution(a) Corrective Tax(b) Pollution PermitsDemand forpollution rightsQPCorrective tax1. A corrective tax sets the price of pollution .

49、. .2. . . . which, together with the demand curve, determines the quantity of pollution.Price ofpollution0Quantity ofpollutionDemand forpollution rightsPQSupply of pollution permits1. Pollution permits set the quantity of pollution . . .2. . . . which, together with the demand curve, determines the

50、price of pollution.Public Policies Toward ExternalitiesObjections to the economic analysis of pollution“We cannot give anyone the option of polluting for a fee.” - by late Senator Edmund MuskiePeople face trade-offsEliminating all pollution is impossible Clean water and clean air opportunity costLow

51、er standard of living 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.28Public Policies To

52、ward ExternalitiesClean environment is a normal goodPositive income elasticityRich countries can afford a cleaner environment More rigorous environmental protectionClean air and clean water - law of demandThe lower the price of environmental protectionThe more the public will want it 2015 Cengage Le

53、arning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.29Private Solutions to ExternalitiesThe types of private

54、solutionsMoral codes and social sanctionsCharitiesSelf-interest of the relevant partiesIntegrating different types of businessesInterested parties can enter into a contract 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as p

55、ermitted in a license distributed with a certain product or service or otherwise on a password-protected website for classroom use.30Private Solutions to ExternalitiesThe Coase theoremIf private parties can bargain without cost over the allocation of resourcesThey can solve the problem of externalit

56、ies on their ownWhatever the initial distribution of rightsInterested parties can reach a bargain in whichEveryone is better offOutcome is efficient 2015 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part, except for use as permitted in a license di

57、stributed with a certain product or service or otherwise on a password-protected website for classroom use.31Private Solutions to Externalities1. Dick has the legal right to keep a barking dog.Dick gets a $500 benefit from the dogJane bears an $800 cost from the barkingEfficient outcome:Jane can offer Dick $600 to get rid of the dogDic