題目：Prices versus Quantities with Policy Updating
主講人：Billy Pizer Professor （Duke University）
時間：2016年5月26日（周四）下午13:30—15:00
地點：北理工主樓六層
主講人簡介：
Billy Pizer is Professor at the Sanford School and Faculty Fellow at the Nicholas Institute, both at Duke University. His current research examines how public policies to promote clean energy can effectively leverage private sector investments, how environmental regulation and climate policy can affect production costs and competitiveness, and how the design of market-based environmental policies can address the needs of different stakeholders. He has examined these questions in variety of international, national, and sub-national contexts, including China. Since 2013, he has co-lead Duke’s effort to create an environment program in China, including Duke Kunshan University’s new Environment Research Center and International Masters in Environmental Policy established in 2016. From 2008 until 2011, he was Deputy Assistant Secretary for Environment and Energy at the U.S. Department of the Treasury, overseeing Treasury’s role in the domestic and international environment and energy agenda of the United States. Prior to that, he was a researcher at Resources for the Future for more than a decade. He has written more than forty peer-reviewed publications, books, and articles, and holds a PhD and MA in economics from Harvard University and BS in physics from the University of North Carolina at Chapel Hill.
內容介紹：
This paper considers the effect of uncertainty on the comparative advantage of price-based regulation over intertemporally tradable quantity regulation when policies are updated. In particular, we examine the case where uncertainty about costs and benefits unfolds over time, and an information asymmetry implies that information known to the firm in one period does not influence government policy until the next period. Under this setup quantity regulation can achieve the first-best outcome and is always preferred to a price instrument when the government sets both policies to maximize expected net benefits. With quantity trading over time, the firm's intertemporal optimization implies current prices equal discounted expected future prices. This allows the government to circumvent the information asymmetry through policy updates that influence future expected prices and, in turn, current prices. No such opportunity exists with price regulation. We also consider the possibility that policy updates are driven in part by political “noise” rather than true values of costs and benefits. Here, we find that price regulation will be preferred if the variance of shocks in the political noise process exceeds the variance of the true shocks to marginal costs and benefits. Applied to climate change or other applications where marginal benefits are at, this condition for preferring price regulation simplifies to whether noise shocks have higher variance than benefit shocks, and cost uncertainty does not matter. All of these results sharply contrast with the Weitzman (1974) results that the relative slopes of marginal costs and benefits determine the comparative advantage of prices versus quantities and that benefit uncertainty by itself does not matter.
（承辦：能源與環境政策研究中心，科研與學術交流中心）
