1、Chapter 3 Valuing The Environment: Methods 1. Introduction Main Contents: Examine the valuation methods Identify 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 valuatio
2、n information cannot reliably be obtained. 2. Valuing Benefits 2.1 Types of Values 2.2 Classifying Valuation Methods 2.3 Valuing Human Life 2.4 Issues in Benefit Estimation 2.5 Approaches to Cost Estimation 2.6 A Critical Appraisal 2.1 Types of Values Economists have decomposed the total economic va
3、lue conferred by resources 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 Values Use value （使用价值）（使用价值）reflects the direct use of the environmental resource. Fish harvested from the sea Timber harvested from the forest Water extracted from a stream fo
4、r irrigation Scenic beauty conferred by a natural vista Pollution can cause a loss of use value. 2.1 Types of Values Option 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
5、 in the future even if one is not 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 Values Nonuse value （非使用价值）（非使用价值）reflects the common observation that people are more th
6、an willing to pay for improving or preserving resources that they will never use. 2.1 Types of Values These 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 Value 2.2 Classifying Valuation Methods 2.2 Classifying Valuation Met
7、hods Direct observation methods （直接观察法） are those which are based on actual observable choices and from which actual resource values can be directly inferred. Direct hypothetical methods （直接假设法） might be used when the value is not directly observable. This approach is called contingent valuation （意愿
8、调查法或条件（意愿调查法或条件 估值法）估值法）which merely asks respondents what value they would place on an environmental change or on preserving the resource in its current state. 2.2 Classifying Valuation Methods Four 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
9、差） Information bias（信息偏差） Starting point 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 Methods Strategic bias （策略性偏差）（策略性偏差）arises when the respondent provides a biased answer in order to influ
10、ence a particular outcome. Information bias （信息偏差）（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 Methods Starting-point bias （初始点偏差）（初始点偏差） may arise in those survey instruments in which a respondent is aske
11、d to check off his or her answers from a predefined range 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 ma
12、y arise when respondents are asked for their willingness to 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 Methods WTP versus WTA: why so different? Psycholog
13、ical endowment effect (禀赋效应) Substitutes （替代品） Characteristics of the 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 Methods Indirect observable methods （间接观察（间接观察 法）法）are “observable” because they involve actual (as opposed to hypoth
14、etical) behavior, and “indirect” because they infer a value rather than estimate 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 Methods Travel-cost methods （旅行成本法）（旅行成本法） may in
15、fer the value of a recreational resource by using information on how much the visitors 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 i
16、nto their component parts. 2.2 Classifying Valuation Methods Hedonic wage value （工资价值法）（工资价值法） 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 th
17、ose designed to reduce the damage caused by pollution by taking some kind of averting or defensive action. 2.2 Classifying Valuation Methods Indirect 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
18、 set of hypothetical situations that differ in terms of the environmental amenity available and other 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 off
19、ers a powerful collection of tools for depicting and examining spatial relationships. 2.3 Valuing Human Life The 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 p
20、lace a value on the change. 2.4 Issues in Benefit Estimation Primary versus secondary effects Are the secondary benefits to be counted? Tangible versus intangible benefits Tangible 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 t
21、hose which cannot be assigned a monetary value. How are intangible benefits to be handled? 2.5 Approaches to Cost Estimation The 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 circums
22、tances facing the firm Engineering approaches are used to derive the actual costs of those technologies, given the special circumstances. 2.6 A Critical Appraisal On the positive side, benefit cost analysis （成本收益分析法）is frequently a very useful part of the policy process. On the negative side, benefi
23、t 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 Analysis Cost-effectiveness analysis （成本有效性分（成本有效性分 析法）析法）frequently involves an optimization procedure. An optimization procedu
24、re 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 Analysis Second Equimarginal Principle（第（第 二等边际原理）二等边际原理） ( The C
25、ost- 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 Analysis What can be done when the information needed to perform a benefit-cost analysis（成本收
26、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 Analysis An impact analysis （影响分析）（影响分析） regardless of whether it focus on economic impact or environmental impact or both, attemp
27、ts to quantify the consequences of various actions. 4. Impact Analysis In 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 analysis a
28、nd 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, 7592 L. Tyrvinen , Antti Miettinen, Property Prices and Urban Forest Amenitie
29、s, Journal 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-222 Liisa Tyrvinen , Hannu Vnnen, The economic value of urban forest amenities: an
30、 application of the contingent valuation +method, Landscape and Urban Planning 43(1998) 105-118 A 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，2002 Objectives & Requirements: Understand and grasp the types of values Understand the methods for valuing benefits and costs of environment Understand the three diffe
31、rent methods for environmental decision Problem: 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
32、 in the area of oil spill prevention. 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?
