An Analytical Framework for Joint vs Separate Decisions by Couples in Choice Experiments: The Case of Coastal Water Quality in Tobago

This paper offers an analytical framework for analyzing joint and separate decisions by couples in the context of choice experiments for nonmarket valuation. It reports results from an attribute-based stated preference study in which members of couples are asked to conduct a choice-experiment first individually and then jointly. The choice context was the selection of which beach to visit while on vacation in Tobago. Available alternatives differed in attributes related to coastal water and beach quality such as level of coastal development and fish abundance. Tests of preference equality are reported and structured so as to identify the intra-couple decision-making patterns under taste heterogeneity with both finite and continuous mixed logit. Results from the latter suggest that women’s preferences are found to be predominant in the joint choice-experiment. Results suggest caution in using individual choice rather than joint couple choice when valuing quality changes impacting on couple activities, such as water and beach quality in Tobago, and call for further research on the topic.     

The Effect of Consumers’ Real-World Choice Sets on Inferences from Stated Preference Surveys

For stated preference (SP) studies, we develop a model that assesses the influence of choice set misspecification arising from the omission of perceived substitutes among real-world alternatives in the same class of goods. This problem is most likely to be present when individuals are allowed to select a “no purchase” option instead of being forced to choose from an explicit set of SP alternatives with hypothetical attribute levels. A convenient feature of our model is that researchers do not need to know exactly which omitted real substitute the individual most prefers, only the set of real substitutes that exists. In our empirical illustration, a comparison of rival models suggests researchers who overlook the presence of perceived real alternatives related to an SP experiment can end up with noticeably biased welfare estimates. Our more-general model suggests that it may be prudent for future SP researchers to anticipate, then test and possibly correct for, distortions in utility parameter estimates that result from this problem.      

Distal order effects in stated preference surveys

Stated preference researchers have previously demonstrated that a good's placement among a sequence of goods in a set of valuation questions (i.e. proximal order effects) can have a substantial impact on people's valuations of these different goods. However, the economic consequences of potential order effects stemming from other questions in a survey, prior to the valuation tasks, have received surprisingly little attention. Using an online climate change survey, we identify order effects created by prior attitude-elicitation questions, and we assess the potential impact of these distal order effects on willingness to pay (WTP) estimates for stylized climate change policies. We find that the order used in prior questions may change people's opinions toward various attributes of the good to be valued, and thereby change WTP by a substantial amount. This paper emphasizes the significance of order effects stemming from preliminary survey questions, and supports a call for diligence in the random ordering of all potentially influential preliminary information in stated preference surveys to minimize inadvertent effects from any single arbitrary ordering.     

Willingness to pay for other species' well-being

Benefit-cost analysis of environmental policies typically focuses on benefits to human health and well-being. For other species, economists have attempted to measure human WTP for changes in the numbers of individuals for different types of wildlife, and to preserve biodiversity. When it comes to humans' WTP for improvements in the quality-of-life for other species, however, the evidence is limited. Morbidity and quality-of-life considerations may be particularly important to the task of valuing non-fatal harm to wildlife in the wake of an environmental disaster. We argue that the other species morbidity-reduction component of WTP should be calculated net of any “outrage” component associated with the cause of the harm. This net WTP is likely to be correlated with the premium that people are willing to pay for chicken products from birds for which the quality-of-life has been enhanced by improved animal welfare measures. This paper uses a conjoint choice stated preference survey to reveal the nature of systematic heterogeneity in preferences for “humanely raised” versus “conventionally raised” chicken. We also use latent class analysis to distinguish between two classes of people—those who are willing to pay a premium for humanely raised chicken, and those who are not.     

Estimation of forest values using choice modeling: An application to Spanish forests

This paper presents a Choice Modeling application of forest goods and services valuation for an afforestation program in the Northeast of Spain. The results from a random parameter logit model reveal that, on average, individuals would annually pay an average of 11.79 euros for the forests to sequester 68,000 tones of CO₂, 0.12 euros for delaying the loss of land productivity for ten years, and 6.33 euros from picnic users for being allowed to picnic in the new forests. On the other hand, individuals would experience a loss in welfare equivalent to − 9.67 euros if four-wheel driving is allowed in the new forests. Finally, being allowed to pick mushrooms in the new forests is valued at an average of 12.82 euros by those who live in rural areas.     

水资源负价值的研究

本文提出了水资源负价值理论,分析了水资源负价值的构成,并给出了计算方法。     

Incentive and informational properties of preference questions

Surveys are frequently used by businesses and governments to elicit information about the public’s preferences. They have become the most common way to gather preference information regarding goods, that are not (or are not yet) bought or sold in markets. In this paper we apply the standard neoclassical economic framework to generate predictions about how rational agents would answer such survey questions, which in turn implies how such survey data should be interpreted. In some situations, the standard economic model would be expected to have no predictive power. For situations where it does have predictive power, we compare different survey formats with respect to: (a) the information that the question itself reveals to the respondent, (b) the strategic incentives the respondent faces in answering the question, and (c) the information revealed by the respondent’s answer. Earlier versions of this paper have been presented as a plenary address to the European Association of Environmental and Resource Economics in Oslo, as an invited paper at the Japanese Forum on Environmental Valuation meeting in Kobe, and at a NOAA conference on stated preference methods.     

Assessing information provision and respondent involvement effects on preferences

We develop a test of the effect of information and respondent involvement on preferences for passive-use values using three treatments. Individuals from a rural community participated in one of three groups, each with a different level of involvement in the valuation assessment. The first group was highly involved, attending three meetings which allowed for information acquisition and preference construction. The second group was involved in a single meeting, and the third group was minimally involved through telephone contact and the completion of a mail administered survey. The hypothesis examined was that the degree of involvement in the exercise would affect the magnitude and consistency of preferences across the groups. The hypothesis that the preferences differ was not accepted. Furthermore, the hypothesis that variances in preferences would be higher in less involved groups was also rejected. While the analysis is based on relatively small samples the findings suggest caution in claiming that increasing degrees of respondent involvement improve economic measures of trade-offs.     

Valuing the Benefits of Coastal Water Quality Improvements Using Contingent and Real Behaviour

Recent moves in the European Union have beenmade towards a toughening of legislation onbathing water quality. This has focussedpolicy-makers thoughts on the welfare benefitsresulting from such improvements, especiallygiven their cost. Our paper uses a combinedstated and revealed preference approach tovalue coastal water quality improvements,focussing on an area of Scotland which hasconsistently failed to meet standards under theBathing Waters Directive. We combine data onreal behaviour with data on contingentbehaviour using a random effects negativebinomial panel model. This allows us to predictboth the change in participation (trips) shouldwater quality be improved, and the welfareincrease per trip. Our model includes allowancefor the existence of substitute sites, and forchanges in recreational behaviour during abeach visit.     

A discrete choice experiment to determine UK patient preference for attributes of disease modifying treatments in Multiple Sclerosis

Aims: The recent licensing of Disease Modifying Treatments (DMTs) for Multiple Sclerosis (MS) has increased available treatment options. The aim of this study was to explore MS patients’ preference for the different attributes of DMTs in the UK.

Materials and methods: Attributes (treatment characteristics) for inclusion in the discrete choice experiment (DCE) were determined through published literature and interviews with 12 people with MS. Seven attributes were selected. Participants were presented with three hypothetical treatment options sampled from included attributes and asked for their most/least preferred options. The influence of patient characteristics and demographics on patient preference was also investigated.

Results: The DCE was completed by 350 people with MS (81% female, mean age?=?39). Results showed that method of taking medication was the strongest determinant of preference (27%; relative importance out of 100%), followed by relapse free rate (21%) and symptom progression (14%). Risk of fatigue (8%) and type of monitoring (6%) were the weakest determinants of preference. Once-daily oral treatment was preferred over all other methods of administration. Participant characteristics did not influence data on strength of preference.

Limitations: This study assumed adequate participant understanding of the discrete choice experiment task, and recruitment targeted those with access to the internet.

Conclusions: These results, derived from people with MS in the UK, should be used to inform individual discussions with patients about DMT choices.     

中国西部地区经济增长质量的评价

改革开放以来,中国西部地区经济发展的成效主要不在干经济增长速度的高低,而在于经济增长质量的优劣,在于经济增长是否使西部地区的人民生活水平得到全面提高。本文从经济增长质量的视角来考察西部地区2004—2008年经济发展状况,通过系统全面的指标体系,用主成份分析法对西部地区的经济增长质量进行综合评价,对改善西部地区现有经济增长方式,提高人民生活质量及进一步推进西部大开发具有重要的理论和现实意义。     

Introduction to the Special Issue: Things We Do and Don’t Understand About the Household and the Environment

Environmental economics has been slow to incorporate the full and complex nature of the household into its analytical structures and to reflect empirical evidence on household decision-making. This paper provides an overview of some of the main unanswered questions.      

The Value of Household Water Service Quality in Lahore,Pakistan

Most existing literature focuses on the benefits of establishing basic drinking water access for unserved populations, the extensive water supply margin. In contrast, this article examines the intensive margin—the benefits of improving water service to under-served households, a growing population in developing country cities. We use contingent valuation to estimate willingness to pay (WTP) for improved piped water quality and reductions in supply interruptions among a sample of 193 households in Lahore, Pakistan. The distribution of WTP is described using parametric and non-parametric models. Results indicate that households in Lahore are willing to pay about 7.50 to7.50 to 9 per month for piped water supply that is clean and drinkable directly from the tap—comparable to the monthly cost of in-home water treatment, and about three to four times the average monthly water bill for sample households using piped water. Estimates of WTP for reducing supply interruptions are both smaller and more difficult to interpret, since a significant fraction of the estimated WTP distribution for supply improvements is negative. All of our WTP estimates are well below 4% of monthly household income, the World Bank’s benchmark upper bound for affordable water service.     

Agricultural landowners⿿ response to incentives for afforestation

Previous research has shown that afforestation of agricultural land is a relatively low-cost option compared to energy-based approaches for mitigating net carbon dioxide emissions, and that financial incentives affect landowner behavior and can be used to increase carbon sequestration on private land. In this paper we use stated preference data from private landowners in the Pacific Northwest region of the U.S. to examine the key factors affecting participation in an incentive program for carbon sequestration through afforestation. We also estimate the corresponding potential for carbon sequestration and its cost. Our results suggest that incentive payments would significantly and positively affect landowners⿿ level of enrollment in a tree planting program.     

Valuations of aircraft noise: experiments in stated preference

The aim of this paper is to report new evidence relating to residents’ valuations of aircraft noise in three countries with an emphasis on a comparison of the valuations obtained using two contrasting approaches. One might be regarded as a standard stated choice approach offering pairwise comparisons of two alternatives characterised by a limited number of attributes. The other choice format adopted is innovative in drawing inspiration from the priority evaluator approach to embed aircraft movements alongside a wide range of other local factors that impact on residents’ quality of life. The paper addresses the differences in the results of the two approaches and explores the possible explanations for these variations. Although not conclusive, there is a suspicion that strategic bias may have influenced the results and we urge further research regarding incentives to such bias.     

城市再生水的需求分析

目前，我国城市再生水回用事业发展的一个主要制约因素就是再生水市场需求非常有限。本文针对这一问题，对城市再生水的需求进行了深入分析，建立了再生水需求函数模型，详细分析了再生水需求的影响因素。最后，在需求分析的基础上，提出了促进再生水回用事业发展的对策建议。     

经济风险视角下中国经济增长质量的评价研究

伴随着社会的进步和经济高速增长,风险问题已经渐渐崭露头角成为经济长足高效增长的障碍。本文通过对于中国经济增长质量中关于经济风险的问题予以研究,并利用熵值分析法计算自建国以来中国经济增长中存在的经济风险。结果表明,自改革开放以后中国经济增长中的经济风险更多的表现为市场风险,因此应该在高效经济增长的同时,切实有效地规避和降低市场风险,从而提高经济增长质量。     

Preferences for environmental quality under uncertainty

Although the expected effects of environmental policies and interventions are rarely known with certainty, stated preference surveys rarely elicit preferences over uncertain environmental outcomes. This article presents empirical results challenging the view that ignoring such uncertainty during preference elicitation is of no consequence so long as people only care about final environmental states. We show that measured preferences for final environmental states, water quality in this case, depend on whether people choose between final states or between lotteries over final states. In contrast to the typical finding for monetary lotteries, we find significant under-weighting of low probability events related to water quality.     

中国经济增长质量问题的初步研究

经济发展包括数量增长和质量提高两个方面.今后我国经济发展的主要问题不是数量增长的快慢,而是经济增长质量的高低.本文运用因子分析方法,对1990年以来中国经济增长的质量进行了实证研究,认为最近几年中国经济增长的质量提高与数量扩张存在较为明显的不同步现象.最后对这种现象的原因做出了初步解释并提出了相应的政策建议.