1、Chapter 3Valuing The Environment:Methods1.IntroductionMain Contents:Examine the valuation methodsIdentify and discuss the various valuation techniques that are used to value environmental resources.Discuss the strategies that exist for using economics to protect the environment when valuation inform
2、ation cannot reliably be obtained.2.Valuing Benefits2.1 Types of Values2.2 Classifying Valuation Methods2.3 Valuing Human Life2.4 Issues in Benefit Estimation2.5 Approaches to Cost Estimation2.6 A Critical Appraisal2.1 Types of ValuesEconomists have decomposed the total economic value conferred by r
3、esources into three main components:Use value（使用价值）Option value（选择价值）Nonuse value（非使用价值）2.1 Types of ValuesUse value（使用价值）（使用价值）reflects the direct use of the environmental resource.Fish harvested from the seaTimber harvested from the forestWater extracted from a stream for irrigationScenic beauty c
4、onferred by a natural vistaPollution can cause a loss of use value.2.1 Types of ValuesOption value（选择价值）（选择价值）reflects the value people place on a future ability to use the environment.Option value reflects the willingness to preserve an option to use the environment in the future even if one is not
5、 currently using it.Whereas use value reflects the value derive from current use,option value reflects the desire to preserve a potential for possible future use.2.1 Types of ValuesNonuse value（非使用价值）（非使用价值）reflects the common observation that people are more than willing to pay for improving or pre
6、serving resources that they will never use.2.1 Types of ValuesThese categories of value can be combined to produce the Total Willingness to Pay(TWP，总支付意愿):TWP=Use Value+Option Value+Nonuse Value2.2 Classifying Valuation Methods2.2 Classifying Valuation MethodsDirect revealed preference methods（直接揭示偏
7、好法）are those which are based on actual observable choices and from which actual resource values can be directly inferred.Direct stated preference methods（直接陈述偏好法）might be used when the value is not directly observable.This approach is called contingent valuation（意愿调查法或（意愿调查法或条件估值法）条件估值法）which merely
8、 asks respondents what value they would place on an environmental change or on preserving the resource in its current state.2.2 Classifying Valuation MethodsFour types of potential bias for using the contingent valuation method（意愿调查法）（意愿调查法）:Strategic bias（策略性偏差）Information bias（信息偏差）Starting point
9、bias（初始点偏差）Hypothetical bias（假设性偏差）The observed discrepancy between willingness to pay(WTP)and willingness to accept(WTA)2.2 Classifying Valuation MethodsStrategic bias（策略性偏差）（策略性偏差）arises when the respondent provides a biased answer in order to influence a particular outcome.Information bias（信息偏差）（
10、信息偏差）may arise whenever respondents are forced to value attributes with which they have little or no experience.2.2 Classifying Valuation MethodsStarting-point bias（初始点偏差）（初始点偏差）may arise in those survey instruments in which a respondent is asked to check off his or her answers from a predefined ran
11、ge of possibilities.Hypothetical bias（假设性偏差）（假设性偏差）can enter the picture because the respondent is being confronted by a contrived rather than an actual,set of choices.Gaps between willingness to pay and willingness to accept compensation may arise when respondents are asked for their willingness to
12、 accept compensation for a specified loss may tend to report much higher values than if asked for their willingness to pay far a specified improvement in quantity.2.2 Classifying Valuation MethodsWTP versus WTA:why so different?Psychological endowment effect(禀赋效应)Substitutes（替代品）Characteristics of t
13、he goods（物品特征）Moral context of the valuation(价值的道德判断）Property rights allocated（产权配置）2.2 Classifying Valuation MethodsIndirect revealed preference methods（间接观察法）（间接观察法）are“observable”because they involve actual(as opposed to hypothetical)behavior,and“indirect”because they infer a value rather than es
14、timate it directly.Travel-cost methods（旅行成本法）Hedonic wage approaches（工资价值法）Hedonic property value（资产价值法）Averting or defensive expenditures（费用支出法）2.2 Classifying Valuation MethodsTravel-cost methods（旅行成本法）（旅行成本法）may infer the value of a recreational resource by using information on how much the visit
15、ors spent in getting to the site to construct a demand curve for willingness to pay for a“visitor day.”Hedonic property value（资产价值法）（资产价值法）studies attempt to decompose the various attributes of value in property into their component parts.2.2 Classifying Valuation MethodsHedonic wage value（工资价值法）（工资
16、价值法）approaches are similar except that they attempt to isolate the component of wages which serves to compensate workers in risky occupations for taking on the risk.Averting expenditures（费用支出法）（费用支出法）are those designed to reduce the damage caused by pollution by taking some kind of averting or defen
17、sive action.2.2 Classifying Valuation MethodsIndirect hypothetical methods（间接假（间接假设法）设法）are illustrated by a technique known as contingent ranking（意愿排（意愿排序法）序法）which means that respondents are given a set of hypothetical situations that differ in terms of the environmental amenity available and othe
18、r characteristics the respondents are presumed to care about,and are asked to rank these situations in terms of their desirability.Using geographic information systems for economic valuation GIS offers a powerful collection of tools for depicting and examining spatial relationships.2.3 Valuing Human
19、 LifeThe economic approach to valuing lifesaving reductions in environmental risk is to calculate the change in the probability of death resulting from the reduction in environmental risk and to place a value on the change.2.4 Issues in Benefit EstimationPrimary versus secondary effectsAre the secon
20、dary benefits to be counted?Tangible versus intangible benefitsTangible benefits（有形收益）（有形收益）are those which can reasonably be assigned a monetary value.Intangible benefits（无性收益）（无性收益）are those which cannot be assigned a monetary value.How are intangible benefits to be handled?2.5 Approaches to Cost
21、EstimationThe survey approach（调查法）The engineering approach（工程法）The combined approach（混合法）The survey approach collects information on possible technologies,as well as special circumstances facing the firmEngineering approaches are used to derive the actual costs of those technologies,given the specia
22、l circumstances.2.6 The Treatment of RiskThe treatment of risk in the policy process involves two major dimensions:Identifying and quantifying the risksDeciding how much risk is acceptable2.7 A Critical AppraisalOn the positive side,benefit cost analysis（成本收益分析法）is frequently a very useful part of t
23、he policy process.On the negative side,benefit cost analysis has been attacked as seeming to promise more than can actually be delivered,particularly in the absence of solid benefit information.3.Cost-Effectiveness AnalysisCost-effectiveness analysis（成本有效性分（成本有效性分析法）析法）frequently involves an optimiz
24、ation procedure.An optimization procedure is merely a systematic method for finding the lowest cost means of accomplishing the objective.This procedure does not produce an efficient allocation because the predetermined objective may not be efficient.3.Cost-Effectiveness AnalysisSecond Equimarginal P
25、rinciple（第（第二等边际原理）二等边际原理）(The Cost-Effectiveness Equimarginal Principle):The least-cost means of achieving an environmental target will have been achieved when the marginal costs of all possible means of achievement are equal.4.Impact AnalysisWhat can be done when the information needed to perform
26、a benefit-cost analysis（成本收益分析）or a cost-effectiveness analysis（成本有效性分析）is not available?The analytical technique designed to deal with this problems is called impact analysis（影响分析）.4.Impact AnalysisAn impact analysis（影响分析）（影响分析）regardless of whether it focus on economic impact or environmental impa
27、ct or both,attempts to quantify the consequences of various actions.4.Impact AnalysisIn contrast to benefit-cost analysis,a pure impact analysis makes no attempt to convert all these consequences into a one-dimensional measure,such as dollars,to ensure comparability.In contrast to both benefit cost
28、analysis and cost-effectiveness analysis,impact analysis does not necessarily attempt to optimize.Further reading:L.Tyrvinen,Economic valuation of urban forest benefits in Finland,Journal of Environmental Management(2001)62,7592L.Tyrvinen,Antti Miettinen,Property Prices and Urban Forest Amenities,Jo
29、urnal of Environmental Economics and Management 39,205-223(2000)Liisa Tyrvinen,The amenity value of the urban forest:an application of the hedonic pricing method,Landscape and Urban Planning 37(1997)21 l-222Liisa Tyrvinen,Hannu Vnnen,The economic value of urban forest amenities:an application of the
30、 contingent valuation+method,Landscape and Urban Planning 43(1998)105-118A 迈克里 弗里曼，环境与资源价值评估理论与方法，中国人民大学出版社，2002Objectives&Requirements:Understand and grasp the types of valuesUnderstand the methods for valuing benefits and costs of environmentUnderstand the three different methods for environmental
31、 decisionProblem:In Mark A.Cohen,“The costs and benefits of oil spill prevention and enforcement”,Journal of Environmental Economics and Management 13,an attempt was made to quantify the marginal benefits and marginal costs of U.S.Coast Guard enforcement activity in the area of oil spill prevention.
32、His analysis suggests that the marginal per-gallon benefit from the current level of enforcement activity is$7.50 while the marginal per-gallon cost is$5.50.Assuming these numbers are correct,would you recommend that the Coast Guard increase,decrease,or hold at the current level their enforcement activity?Why?
