Environmental Law and Policy
---- Acknowledgements -----
Katharine Emans, Nicholas Bagley, and Gernot Wagner provided valuable research assistance, and helpful comments on previous versions were provided by Dallas Burtraw, Daniel Esty, Myrick Freeman, Robert Hahn, Louis Kaplow, Nathaniel Keohane, Charles Kolstad, Peter Menell, Richard Newell, Sheila Olmstead, Mitchell Polinsky, Paul Portney, Steven Shavell, and Kerry Smith. The authors alone are responsible for any remaining errors. The views expressed herein are those of the author(s) and do not necessarily reflect the views of the National Bureau of Economic Research.