环境影响的费用效益要点详解.ppt

货币汇率（Foreign exchange） S D ￥ per ＄ ＄ Shadow price Exchange rate Import quota 外部性问题（Externality） ?Definition: An externality is present where the well-being of a consumer or production possibilities of a firm are directly affected by the action of another agent in the economy. 外部性问题（Externality ） To obtain efficient output level of good which generates a negative externality, needs to consider TSC: Total social cost = private production cost + external cost imposed on others? Negative Externality ——Example of steel: Total social cost = Total private cost + Total external cost Efficient output level of steel Maximize net benefit = Gross benefit – Total social cost; where MB (Q*) = MSC (Q*) Negative Externality ——Example of steel: Market equilibrium: (Q^, P^) P^ ≠ MSC or MB ≠ MSC Q^ Q* MSC (Q) MPC(Q) Environmental cost Q* Q^ P^ Deadweight loss due to extra production MB P* VALUING BENEFITS AND COSTS IN SECONDARY MARKETS Valuing Benefits and Costs in Undistorted Secondary Markets Valuing Benefits and Cost in Distorted Secondary Markets Conclusion 1: 如果初级市场上的福利（剩余）的变化得到充分计量，而次级市场上不存在扭曲，那么，无论次级市场是否发生价格变化，都不必再考虑次级市场。 Conclusion 2: ?对于存在市场扭曲的次级市场，如存在环境污染、消费税征收等, 应当测算所有的次级市场上发生的社会剩余的变化。但如果引发的社会剩余变化不大，也可忽略。 三、对“非市场物品”的价值评估 Valuation on Nonmarket items： Benefit/cost associated with unmarketed output or inputs, such as, time，pollution，ecological value—biodiversity，recreational facilities，the value of saving life，et.al EX: Value of the saving of a “statistical life” Maximum amount that would be paid by the members of society to secure an increase in the number of “statistical lifes” EX: Value of the saving of a “statistical life” “Status quo”: M users, m1 member of users are expected to die. m1 M probability of a death= m1/M EX: Value of the saving of a “statistical life” with a project : M users m2: number of users expected to die m2 m1 let Δm=m1 – m2 (number of expected deaths prevented) Reduction in the prob