Testing the Consistency Between Standard Contingent Valuation,Repeated Contingent Valuation and Choice Experiments

Choice experiments (CEs) are a relatively new approach to valuing environmental resources. Initial tests of the validity of the approach have either compared benefit estimates generated using CEs with those estimated using contingent valuation (CV) or used more sophisticated hypothesis tests of parameter equality. Although useful, existing tests have been restricted to testing consistency based on a single policy scenario (standard CV). We argue that, although these tests are informative, they fail to take full advantage of the richness of CE data. In particular, CE data allow for the calculation of benefit estimates over a range of policy scenarios (i.e. attribute combinations). A similar range of benefit estimates may be generated by pooling scenarios in a repeated CV study. In this paper, we explore this relationship between CV and CEs by conducting validity tests between a CE model and a repeated CV model over a range of three levels of improved water quality at Clear Lake, IA, USA. Evidence from this test suggests that the CE and CV data are consistent.     

Extending the framework of the economic evaluation of erosion control actions in Mediterranean basins

Traditionally, the benefits of erosion control projects in Mediterranean watersheds were valued by the replacement cost method (RCM). Nowadays, however, environmental economics has provided alternative methods, such as contingent valuation (CV) and others based on stated preferences, the main strength of which is their capacity to capture non-use and future use values, which are essential for the monetary valuation of erosion. This study uses CV to estimate the externalities associated with watershed restoration and erosion control projects conducted in the Aljibe Basin (Almería, Spain). Comparison shows that CV estimates of net environmental benefits are almost double those obtained using standard methods. Thus, the project meets the profitability criteria in the former case but not in the latter. In concrete terms, the Internal Rates of Return are 5.23% versus 2.25%, respectively. The above shows CV to be a useful tool for estimating the social-environmental return on investment in this kind of project. However, as the experimental phase of this study shows, CV is not without certain issues and limitations, the majority of which derive from its hypothetical nature. Moreover, being preference-based, it may be more coherent with a cost-benefit analysis approach. The RCM, on the other hand, is highly detailed in technical terms and, by using physical data, produces more objective results. The two can therefore be considered complementary rather than competing methods, since they view the valuation from different perspectives.     

Yield Effects of Tissue Culture Bananas in Kenya: Accounting for Selection Bias and the Role of Complementary Inputs

We analyse yield effects of tissue culture (TC) banana technology in the Kenyan small farm sector, using recent survey data and an endogenous switching regression approach. TC banana plantlets, which are free from pests and diseases, have been introduced in East Africa since the late 1990s. Although field experiments show significant yield advantages over traditional banana suckers, a rigorous assessment of impacts in farmers’ fields is still outstanding. A comparison of mean yield levels between TC adopters and non‐adopters in our sample shows no significant difference. However, we find evidence of negative selection bias, indicating that farmers with lower than average yields are more likely to adopt TC. Controlling for this bias results in a positive and significant TC net yield gain of 7%. We also find that TC technology is more knowledge intensive and more responsive to irrigation than traditional bananas. Simulations show that improving access to irrigation could lift TC productivity gains to above 20%. The analytical approach developed and applied here and the finding of negative selection bias may also be relevant for the evaluation of other agricultural technologies.     

Spatial plans as relational data: Using social network analysis to assess consistency among Bucharest’s planning instruments

Globally, planning instruments help shape the development of places under uncertain future conditions. In the context of a multi-level planning system, both land-use and strategic spatial plans are available, mandated by different policies and adopted by various authorities. Notwithstanding the excellent support consistency among such plans can provide for their transformative capacity, studies analyzing how plans interact, forming complex relationships, are rare. Treating plans as relational data gives insights into the outcomes acquired by a network compared to the transformations enabled by a single plan. As the theory of networks prevails for handling relational data, we applied social network analysis to evaluate external consistency among 10 plans of Bucharest, Romania and the surrounding region. All plans are currently in force, have spatial implications, and refer to different administrative levels and sectors, from the metropolitan to the sub-district level and from land-use and transportation to environmental plans. We first developed a framework for consistency assessment, covering four categories of external consistency. Second, following these categories, we extracted relevant plan statements from all plans. Third, we assigned one-way, symmetrical and contradictory relationships between the plan statements. Fourth, using directed and valued network analyses we assessed consistencies, inconsistencies and contradictions between plans. Finally, we validated the results by applying questionnaires to local experts. Our results indicate that consistency among Bucharest’s plans is high on a temporal scale regarding issues and general measures, but low for spatialized planning intentions on both vertical and horizontal scales. We discuss consequences of these findings for the transformative capacity of plans and the effectiveness of plan-implementation.     

An experimental approach to valuing new differentiated products

An experimental store was created to evaluate initial demand for locally produced and guaranteed tender steak products as a more realistic alternative to contingent valuation (CV) and dichotomous-choice experimental methods. Strengths of the approach are incentive compatibility, a realistic consumption set, and a familiar choice environment. Consumers selected among USDA Choice, premium quality, lean, guaranteed tender and locaily produced strip steaks. A double-hurdle count data model indicated initial willingness-to-pay (WTP) for locally produced steak comparable to prior CV results, but demand was highly elastic. Demand for premium quality steak crowded out demand for the guaranteed tender product, contrasting with prior dichotomous-choice experimental results.     

Revisiting the Impact of Order Effects on Sensitivity to Scope: A Contingent Valuation of a Common‐Pool Resource

While many studies have employed stated preferences methods to estimate the value of non‐market ecosystem goods and services, contingent valuation (CV) still generates a significant amount of criticism. Besides ethical concerns, two of the key criticisms relate to insensitivity to scope and order effects. We examine the expectation that the presence of order effects in stepwise disclosure procedures affects the degree of scope sensitivity. We use data from a CV exercise asking farmers in Southern Spain to value two different levels of guarantee of water supply for irrigation in a context of water scarcity. We find that despite order effects being present, they do not affect the existence or the degree of sensitivity to scope. We conclude that, in the light of the mixed evidence found in the literature and the results of our study, it does not seem justified to ascribe order effects and their connection with sensitivity to scope to study design alone (e.g. step‐wise versus advanced disclosure, top‐down versus bottom‐up). The nature of the environmental good under valuation also matters. Our study of irrigation water as a common‐pool resource suggests that, when clear private benefits also exist, these appear to override any ‘good cause dumping effect’ that might arise from the public good component.     

Estimating the benefits of farm animal welfare legislation using the contingent valuation method

This paper presents the method and findings of a contingent valuation (CV) study that aimed to elicit United Kingdom citizens' willingness to pay to support legislation to phase out the use of battery cages for egg production in the European Union (EU). The method takes account of various biases associated with the CV technique, including ‘warm glow’, ‘part‐whole’ and sample response biases. Estimated mean willingness to pay to support the legislation is used to estimate the annual benefit of the legislation to UK citizens. This is compared with the estimated annual costs of the legislation over a 12‐year period, which allows for readjustment by the UK egg industry. The analysis shows that the estimated benefits of the legislation outweigh the costs. The study demonstrates that CV is a potentially useful technique for assessing the likely benefits associated with proposed legislation. However, estimates of CV studies must be treated with caution. It is important that they are derived from carefully designed surveys and that the willingness to pay estimation method allows for various biases.     

Heterogeneous information exposure and technology adoption: the case of tissue culture bananas in Kenya

Classical innovation adoption models implicitly assume homogenous information flow across farmers, which is often not realistic. As a result, selection bias in adoption parameters may occur. We focus on tissue culture (TC) banana technology that was introduced in Kenya more than 10 years ago. Up till now, adoption rates have remained relatively low. We employ the average treatment effects approach to account for selection bias and extend it by explicitly differentiating between awareness exposure (having heard of a technology) and knowledge exposure (understanding the attributes of a technology). Using a sample of Kenyan banana farmers, we find that estimated adoption parameters differ little when comparing the classical adoption model with one that corrects for heterogeneous awareness exposure. However, parameters differ considerably when accounting for heterogeneous knowledge exposure. This is plausible: while many farmers have heard about TC technology, its successful use requires notable changes in cultivation practices, and proper understanding is not yet very widespread. These results are also important for other technologies that are knowledge‐intensive and require considerable adjustments in traditional practices.     

RESPONDENTS TO CONTINGENT VALUATION SURVEYS: CONSUMERS OR CITIZENS (BLAMEY,COMMON AND QUIGGIN,AJAE 39:3) — A COMMENT

Blarney, Common and Quiggin (1995) (BCQ) suggest that responses to contingent valuation (CV) questionnaires may be framed either according to the extent of individual benefits received, or according to wider views about ethical frameworks, impacts on other people, or desired societal levels. They characterise the individual benefit approach as a consumer model, and responses indicating wider concerns as citizen preferences. Citizen value responses are held to invalidate the economic assumptions underlying the use of CV. Hence, they hypothesize that the incorporation of CV results into benefit-cost analysis is problematic. In this comment we suggest that there are several flaws with the citizen value hypothesis. These can be grouped into arguments about the existence of citizen values based on ethical or altruistic grounds, and arguments about the identification of citizen values.     

A Nonparametric Test of the Traditional Travel Cost Model

The traditional travel cost model operates on the assumption that choices are made regarding the number of trips to various sites over an entire recreation season. This paper uses actual recreation data to test the consistency of this model with postulates of rational economic choice as embodied in the axioms of revealed preference. The paper assumes consumer rationality and examines the effects of alternative trip prices and model structures on the degree of consistency between them and the axioms of choice. Using tests developed by Varian and Tsur, the authors find that site choices at prices proxied by travel costs for most individuals in the sample violate the axioms. The violations are quite large when time costs, both in traveling and on-site, are omitted from the prices. When they are included, violations are almost as numerous, but not as large. The paper also examines demand heterogeneity by stratifying the sample and repeating the nonparametric tests. These findings suggest caution be used in interpreting welfare measures derived from traditional travel cost models, especially those that do not include measures of time value. The authors' approach provides a method for screening travel cost data and preparing for model selection and estimation.     

Contingent Valuation Versus Choice Experiments: Estimating the Benefits of Environmentally Sensitive Areas in Scotland: Comment

Following Boxall et al. (1996), Hanley et al. (1998) compare welfare measures derived from contingent valuation (CV) to those derived from choice experiment (CE). Using the same Gumbel distribution assumption of the unobserved component of indirect utility, they estimate welfare measures that they expect to be the same. However, they fail to acknowledge that the indirect utility specifications underlying the two sets of estimates differ. Hence, they do not compare like with like and the difference in welfare estimates cannot be definitely attributed to the difference in the two stated preference methods employed. This comment argues that their econometric analysis is flawed and does not support many of their concluding remarks. Further, disagreement is expressed with their alleged findings on the potential performance of CV in benefit transfer studies.     

中国沿海地区渔业国际竞争力的省际比较和分析

本文在对渔业省际竞争力的内涵及其评价体系进行初步界定后,运用国际市场占有率、贸易竞争指数、显示性比较优势指数对沿海地区渔业竞争业绩进行了评估,并在此基础上运用因子分析法对沿海地区各省市渔业竞争条件进行综合评价和排序。比较研究发现,无论从竞争业绩还是从竞争条件来看,沿海地区各省市渔业国际竞争力呈现较为明显的三个等级,从发展趋势看,这一竞争局面保持相对稳定态势。最后根据分析结果提出了相应的政策建议。     

Convergent validity between revealed and stated recreation demand data: Some empirical evidence from the Basque Country,Spain

In a travel cost exercise, reported past visits to mount Jaizkibel, a natural area located in the Basque Country (Spain), are compared for convergent validity to stated intended future trips under the assumption that the natural resource's conditions will remain the same. In line with the results obtained by other studies, the empirical evidence of this application suggests that revealed preferences (RP) and stated preferences (SP) do not produce consistent data, i.e. do not achieve convergent validity. The paper deals with the convergent validity literature in continuous-choice studies by using two-staged count data models for recreation demand. Differences in preference structures and welfare estimates are tested assuming both common and different data generating processes for the RP and SP data.     

POI数据辅助下的泸州市城市地块用地类型现状快速判断与验证

［目的］土地利用规划和城市规划的用地地块,在实际使用过程中,都会不同程度与规划用途产生差异,如何把握规划的实施程度是土地管理中的一个重要问题。［方法］在大数据时代的背景下,通过对网络大数据可以真实地反映城市地块的真实使用状况。研究采用OSM（Open Street Map）,对研究区进行城市地块的划分,形成街区尺度的城市地块。采用POI（Point of Interest）数据,建立了POI分类与城市用地分类的映射关系,计算了不同类型的POI数据的频数密度和类型比例,形成基于POI的城市地块用地类型识别方法,对研究区的城市地块进行土地利用现状识别。识别结果与第二次土地调查分类结果进行对比,验证方法的可行性。［结果］从泸州市的实证结果看,基于POI数据的城市地块识别结果与基于地籍数据的城市地块识别结果存在很大的差别。地籍数据主要是表针城市地块中不同实体的土地利用状况,两种数据采集的标准和表达的意义都不同,因此造成结果存在较大的差异性。［结论］研究认为,POI点有准确的空间位置信息和丰富的属性信息,主要是表征城市地块中不同实体的真实使用状况,可以较准确地判定快速发展的城市进程中的城市用地类型,能较为真实反映城市地块的现实使用状况,但也要注意POI数据在实际应用中存在的缺陷和不足。     

Farmers’ Willingness to Pay for a Tuberculosis Cattle Vaccine

We use contingent valuation (CV) and choice experiment (CE) methods to assess cattle farmers’ attitudes to and willingness to pay (WTP) for a bovine tuberculosis (bTB) cattle vaccine, to help inform vaccine development and policy. A survey questionnaire was administered by means of telephone interviews to a stratified sample of 300 cattle farmers in annually bTB‐tested areas in England and Wales. Farmers felt that bTB was a major risk for the cattle industry and that there was a high risk of their cattle getting the disease. The CE estimate produced a mean WTP of £35 per animal per single dose for a vaccine that is 90% effective at reducing the risk of a bTB breakdown and an estimated £55 for such a vaccine backed by 100% insurance of loss if a breakdown should occur. The CV estimate produced a mean WTP of nearly £17 per dose/per animal/per year for a vaccine (including 100% insurance) which, given the average lifespan of cattle, is comparable to the CE estimate. These WTP estimates are substantially higher than the expected cost of a vaccine which suggests that farmers in high risk bTB ‘hotspot’ areas perceive a substantial net benefit from buying the vaccine.     

呼伦贝尔植被蒸散发时空变化研究

［目的］蒸散发是影响陆地和大气系统能量交换过程的关键因素,也是评价陆地生态系统的重要指标。文章运用中分辨率成像光谱仪(MODIS MOD16A2和MOD13A1)产品数据,并结合中国气象数据共享网的气象数据,估算了2008—2017年呼伦贝尔植被的蒸散发量,并在年度和季节两个时间尺度开展了植被蒸散发时空变化分析。［方法］运用变异系数(CV)和突变检验法(Mann Kendall）,研究2008—2017年呼伦贝尔地区年际和季节蒸散发时空变化趋势。使用Pearson相关分析法,对呼伦贝尔地区季节尺度的蒸散发与归一化植被指数(NDVI)、各气象要素进行相关分析。［结果］2008—2017年呼伦贝尔地区蒸散发呈上升趋势,蒸散发值较大的月份为3月、8月和11月,蒸散发主要集中在5—10月份。变异系数的空间分布较均匀,平均变异系数为038,变异系数变化幅度较大的区域主要集中在呼伦贝尔北部,CV值均在1～265。CV变化幅度较小的区域主要分布在呼伦贝尔中部和南部,CV值在041～084。从年际变化趋势来看, 2013年为一个蒸散发突变年; 根据呼伦贝尔月份变异系数的计算,从1—12月变异系数幅度变化较大,说明呼伦贝尔ET变异剧烈。呼伦贝尔月份平均CV值是1,草原区的CV平均值是096,森林区的CV平均值是104,农区的CV平均值097。植被蒸散发与气象要素关系分析表明：蒸散发与气温、水汽压、NDVI、降水、日照时数呈显著正相关关系。［结论］2008—2017年呼伦贝尔地区蒸散发总体呈上升趋势,从整个季节变化来看,蒸散发起伏变化趋势明显,波动变化较大。从空间分布上来看,总体表现为呼伦贝尔南部的蒸散发大于北部。蒸散发主要集中在4—10月份,多年的低值出现在5月。不同区划类型平均蒸散发量由大到小依次为草原区＞农区＞森林区,全区的蒸散发变化趋势与农区变化趋势较为一致。正相关性强度依次为气温＞日照时数＞NDVI＞水汽压＞降水＞风速。     

农村宅基地整理的自组织何以可能 ——基于公共池塘资源治理的视角

研究目的：基于公共池塘资源治理的视角,采用制度分析与发展（IAD）框架,以浙江省的典型实践为例,探讨农村宅基地整理的自组织模式产生的原因,为因地制宜改善农村人居环境和建设美丽宜居乡村提供学理支撑和路径参考。研究方法：理论分析法、案例分析法。研究结果：（1）农村宅基地资源规模和农户数量的化整为零可以减轻自组织宅基地整理的阻力;（2）具有充分的社会资本积累和积极有为的村庄领导者的农村社区以及自愿性和利益一致性较强的农户群体倾向于采用自组织模式实施宅基地整理;（3）自组织的宅基地整理还离不开符合地方实际的决策制定、行为选择、信息沟通、成本—收益分配等规则。研究结论：研究提供了来自中国农村宅基地整理的经验证据,印证了公共池塘资源治理的自组织模式成因的经典论断;实践中可以鼓励、引导和支持农户结合自身特征,适应好或利用好宅基地资源条件、农村社区特征和起作用的规则,以自组织模式推进农村宅基地整理。     

Protest responses and community attitudes toward accepting compensation to host waste disposal infrastructure

Despite the use of host community compensation to solve NIMBY (Not In My Back Yard) siting difficulties in many industrialised countries, the effectiveness of this policy is still being debated in academic and policy-making arenas. In this paper, we examine attitudes held regarding compensation in communities directly impacted upon by final waste disposal infrastructure projects (landfill and incineration) in Ireland using survey responses to two contingent valuation (CV) scenarios and a question relating to preferences for compensation delivery. We find that communities in the pre-construction planning phase for locally undesirable development are less accepting of compensation offers to host the facility than are communities who have lived with such developments to host an extension to the existing facility in their localities. However, many of our respondents who initially reject compensation offers in the CV question go on to accept at least one compensation package in the later compensation preference question. Using this information allows us to draw a distinction between ‘Hardcore’ and ‘Switcher’ protesters to illustrate a more subtle picture of rejection of locally undesirable facilities and compensation packages than has previously been articulated. Using probit regression analysis, we find that property rights or NIMBY concerns – specifically, the treatment of non-local waste at the facility is a concern for many residents – drive this rejection of compensation. Finally, contrary to previous studies concerning preferences for host compensation, community compensation is not always preferred to individual compensation payments.     

中国人参生产效率研究——基于HMB指数的评价

本研究利用1998~2005年中国人参生产投入产出面板数据(Panel Data),采用非参数HMB指数方法和数据包络分析(DEA)法对人参生产效率进行分析。结果表明:中国人参生产全要素生产率(TFP)变动主要受规模效率改善的影响;各样本区的全要素生产率存在一定差异,除规模效率差异的原因外,还有技术进步和技术效率方面的差异;混合效率的作用不显著;人参生产中的非效率是由于投入冗余、产出不足以及成本收益率低等原因导致的。因此,今后为进一步提高人参生产率,可以通过促进技术进步,提高投入产出比例等手段来实现。