Transport pricing is high on the political agenda throughout the world, but as the authors illustrate, governments seeking to implement this often face challenging questions and significant barriers. The associated policy and research questions cannot always be addressed adequately from a...

"The NBER Bulletin on Aging and Health provides summaries of publications like this. You can sign up to receive the NBER Bulletin on Aging and Health by email. Technological progress is typically a result of trial-and-error research by competing firms. While some research paths lead to the...