Estimating market power is often complicated by a lack of reliable marginal cost data. Instead, policy-makers often rely on summary statistics of the market, thought to be correlated with price cost margins? such as concentration ratios or the HHI. In many industries, these summary statistics...

"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. Efforts to reduce greenhouse gas emissions in the US have relied on Corporate Average Fuel Economy (CAFE) Standards and Renewable Fuel...