A Pigovian tax (also spelled Pigouvian tax) is a tax levied on a market activity that generates negative externalities. The tax is intended to correct the market outcome. In the presence of negative externalities, the social cost of a market activity is not covered by the private cost of the activity. In such a case, the market outcome is not efficient and may lead to over-consumption of the product. A Pigovian tax equal to the negative externality is thought to correct the market outcome back to efficiency.

Pigovian taxes are named after economist Arthur Pigou who also developed the concept of economic externalities. William Baumol was instrumental in framing Pigou's work in modern economics.

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Emission trading schemes: potential revenue effects, compliance costs and overall tax policy issues  Original
Energy Policy, Volume 37, Issue 11, November 2009, Pages 4595-4603
Jeff Pope, Anthony D. Owen

Environmental levies and distortionary taxation:: Pigou, taxation and pollution  
Journal of Public Economics, Volume 87, Issue 2, February 2003, Pages 313-322
Gilbert E. Metcalf, NBER

The Pigou Problem
Nye, John V. C.1Source:Regulation; Summer2008, Vol. 31 Issue 2, p32-37, 6p

多谢！！！！！！！！！！！！！！！