We study estimation and inference in panel data regression models when the regressors of interest are macro shocks, which speaks to a large empirical literature that targets impulse responses via local projections. Our results hold under general dynamics and are uniformly valid over the degree...

This paper casts doubt on empirical results based on panel estimations of an "inverted-U" relationship between per capita GDP and pollution. Using a new data set for OECD countries on carbon dioxide emissions for the period 1960-1997, we find that the crucial assumption of homogeneity across...