Eliminating Errors in Evaluating Environmental Monetary Value through Application of Two-Bounded Dichotomous Choice Model of Contingent Valuation Method
应用两阶段二分式虚拟市场评价法消除环境价值货币评估的偏差

Contingent Valuation Method(CVM) is the most universal approach used in evaluating environmental monetary value.Despite CVM has already developed its economic theoretical framework over the past decades the concomitant problem is the result of CVM is impressionable to the possible errors.Thus the reliability of CVM is often in debate.In recent years,a two-bounded dichotomous choice model has been developed and has become the most widely adopted model in CVM as it may eliminate possible errors to the utmost.This paper discussed economic theoretical framework of CVM and deduced mathematical model of calculating willingness to pay(WTP) by using the two-bounded dichotomous choice model,and explained the details of questionnaire design and WTP estimation through a case study of the Project for Combating Sandstorm affecting Beijing-Tianjin Metropolitan Region.To improve atmospheric quality influenced by sandstorm in Beijing-Tianjin metropolitan region,a project to combat sandstorm in Inner Mongolia was initiated since March 2000 with ten-year duration.The environmental monitoring data indicate that the number of days in which atmospheric quality is better than second-class has increased from 177 in 2000 to 229 in 2004.It shows that restoration of ecological system in windward areas has positive contributions to improvement of atmospheric quality in leeward areas.This paper estimates the monetary value of environmental benefits of improving atmospheric quality during spring(from March to May) in leeward areas,which is brought by the project of combating sandstorm in windward areas.Based on analysis of field survey of 723 respondents from 6 sub-districts in Beijing in April 2005,the results show that the median of residents' WTP is 95 RMB per household per year if an environmental tax was introduced as ecological compensation to windward areas for environmental benefits from improvement of atmospheric quality in leeward areas.The annual environmental tax amounts for 3.9 million RMB as the number of households is 4.1 million in Beijing area,and the total environmental tax in the period is 19.5 million RMB.The study in this paper indicates that the two-bounded dichotomous choice model may eliminate errors from monetary evaluation of environmental benefits to the utmost and it is possible to introduce ecological compensation for environmental benefits,which is brought by other regions.