Environmental prices, uncertainty, and learning
针对环境定价中的不确定性难题，以气候变化为例，提出设定影子价格的实际步骤，包括确定环保目标、制定价格以及通过政策绩效学习来调整目标和价格。
There is an increasing demand for putting a shadow price on the environment to guide public policy and incentivise private behaviour. In practice, setting that price can be extremely difficult as uncertainties abound. There is often uncertainty not just about individual parameters but about the structure of the problem and how to model it. A further complication is the second-best nature of real environmental policy making. In this paper, we propose some practical steps for setting prices in the face of these difficulties, drawing on the example of climate change. We consider how to determine the overall target for environmental protection, how to set shadow prices to deliver that target, and how we can learn from the performance of policies to revise targets and prices.