Using Choice Experiments to Value the Environment

This paper we outline the “choice experiment” approach to environmental valuation. This approach has its roots in Lancaster's characteristics theory of value, in random utility theory and in experimental design. We show how marginal values for the attributes of environmental assets, such as forests and rivers, can be estimated from pair-wise choices, as well as the value of the environmental asset as a whole. These choice pairs are designed so as to allow efficient statistical estimation of the underlying utility function, and to minimise required sample size. Choice experiments have important advantages over other environmental valuation methods, such as contingent valuation and travel cost-type models, although many design issues remain unresolved. Applications to environmental issues have so far been relatively limited. We illustrate the use of choice experiments with reference to a recent UK study on public preferences for alternative forest landscapes. This study allows us to perform a convergent validity test on the choice experiment estimates of willingness to pay.     

基于离散选择模型的顾客选择偏好分析

准确把掌握细分市场上消费者的需求和选择偏好是企业获取较好市场回报的关键.本文以访谈和调查问卷的数据信息为基础,针对消费者个体特征方面的多个因素变量,运用离散选择模型,研究对液态奶制品的某个特征因素作为首选因素的影响分析.同时,针对消费者某一特征因素对液态奶的多个特征因素的选择偏好的影响,给出了基于Logit模型和SPSS软件的统计分析和合理解释.通过对液体奶制品消费者的个体特征和选择液态奶的某一特定因素为首选因素的关系分析,以及顾客选择偏好方面的探讨,为我国液态奶制品供应链在目标市场的选择方面提供了一些启示.     

What You Don’t Know Might Hurt You: Some Unresolved Issues in the Design and Analysis of Discrete Choice Experiments

The papers and comments in this issue focus on four broad areas related to understanding and modeling choices: (1) The use of laboratory experiments to improve valuation methods; (2) The design of stated preference choice set and choice occasions; (3) Latent class models as means of identifying and accommodating preference heterogeneity; and (4) Accommodating uncertainty about the “true” model, modeling ranking and rating tasks and pooling data sources. In what follows I offer some comments on each area, and briefly discuss several unresolved issues associated with each area, closing with some comments about future research opportunities.     

The effect of individual ‘ability to choose’ (scale heterogeneity) on the valuation of environmental goods

Environmental valuation methods, such as choice experiments, are increasingly being used to value complex and often unfamiliar environmental goods. A potential risk is that some survey respondents may not be capable of developing and expressing preferences for such goods. The noise from these individuals may then conceal the well-defined preferences of other respondents and affect valuation estimates. We address this problem by estimating a range of models that accounts for scale heterogeneity (which we interpret as a respondent's ability to choose: ATC) and taste heterogeneity. These models are applied to two case studies: amenity from coastal defence and biodiversity. In both case studies, model fit was improved in a scale-heterogeneity multinomial-logit (S-MNL) model (compared to a standard MNL model) suggesting the accounting for ATC (scale heterogeneity) improved preference revelation. A mixed multinomial-logit (MIXL) model outperformed the S-MNL model suggesting that accounting for taste heterogeneity was also important. However, a generalised multinomial-logit (G-MNL) model improved model fit over the MIXL model only for the biodiversity data suggesting that for these data both taste heterogeneity and ATC were important. We conclude that accounting for ATC can improve the reliability and robustness of the results when valuing complex or unfamiliar environmental goods.     

中国农村劳动力迁移影响因素研究——基于Probit模型的实证分析

农村劳动力迁移对于缩小城乡收入差距、促进中国经济增长具有非常重要的作用。本文通过中国健康与营养调查(CHNS)数据库的成人调查问卷2004和2006年的数据,采用probit模型定量分析了中国农村劳动力迁移的影响因素。本文的研究发现:婚姻状况、健康、娱乐偏好等变量对农村劳动力的迁移决策有比较显著的影响,而当前收入的影响并不明显。此外,家庭负担并不是迁移决策的影响因素,并且已婚女性劳动力倾向于和丈夫共同迁移,以上两个因素共同导致了农村的空巢老人问题。最后,促进农村劳动力迁移的最有效方法是提高农村劳动力的受教育水平,其中大学及大专学校教育最有效,其次是职业和技术学校教育。     

家庭生育选择行为影响因素测度及经济分析——基于离散选择经济计量模型分析视角

我国生育选择特征表现在:对子女数量的追求由多变少、男孩与女孩相比的效用优势正逐步消失、农村家庭正从生育行为转向教育行为。教育和职业对生育模式的选择影响最大,其次是年龄和婚姻状态。基于分析结果,笔者认为,促进人力资本的教育投资、消除收入分配与就业之间的差距、建立公平的社会保障制度等,将有利于强化计划生育政策的积极影响。