基于选择联合分析法的不同群体环境变动偏好分析

目前,中国环境价值评估领域中基于选择联合分析法的案例未见报道。运用基于选择联合分析法分析城市居民对水环境变化的支付意愿,选取1 040个样本户,实地调查江西省九江市柘林湖下游城市居民对柘林湖水环境变化的支付意愿,结果表明:基于选择联合分析法能够更精确地揭示边际支付意愿的变动,Clogit模型分析结果显示居民对水质改善的偏好高于对供水稳定性改善的偏好;整体样本组不含交叉项模型支付意愿估计结果为17.57元/月/户,含交叉项模型估计结果为17.54元/月/户,是否加入收入与环境属性交叉项对支付意愿估值影响不大。不考虑抗议性群体的分析表明,直接估计样本量的支付意愿会造成估值结果低估;非本地户籍家庭较本地户籍家庭对公共物品"搭便车"的心理更加明显;非环保组的支付意愿要高于环保组的支付意愿;低收入组的边际支付意愿要高于样本整体组,与预期结果不一致,建议进一步深入研究。

Estimate on Different Groups'Preferences for Water Environmental Changes Using Choice-based Conj oint Analysis

Choice-Based conj oint analysis was not applied into the field of environmental valuation in china,at this context,Zhelin Lake as a case study is used in this paper.A sample of 1040 urban households in the downstream of Zhelin Lake,a drinking water source for Jiujiang Municipality,were interviewed for their willingness to pay for changes in the water environment of the Zhelin Lake.Choice-based Conj oint analysis was used to estimate urban households'willingness to pay (WTP ) for the environment change.It indicated that Choice-based conjoint analysis could better estimate the marginal WTP.Clogit model results show that downstream households were more sensitive to the water quality improvement rather than stability of water supply.The WTP of whole sample group model without cross-term is 17.57 CNY per household per month,17.54 CNY per household per month estimated by model with cross-term.Inclusion of cross-term of income and changes in environmental attributes in the model analysis has little impacts on the valuation of willingness to pay. WTP varies across groups and contributing factors include environmental awareness for one's own interests,altruist environmental awareness,whether or not from a family with chronic patients,income,gender,hukou,age,whether or not from a family with old members or kids,stable job,decision making in a family.The WTP of not environment-friendly group is higher than that of environment-friendly group.The WTP of low-income group is higher than that of the whole sample.These do not conform to expectations and more studies are needed.