There is good reason to believe that R&D influences on TFP growth in other sectors are indirect. For R&D to spill over, it must first be successful in the home sector. Indeed, observed spillovers conform better to TFP growth than to R&D in the upstream sectors. Sectoral TFP growth rates are thus...

In contrast to the very large literature on skill-biased technical change among workers, there is hardly any work on the importance of skills for the entrepreneurs who employ those workers, and in particular on their evolution over time. This paper proposes a simple theory of skill-biased change...

Surface soil contamination has been long recognized as an important pathway of human lead exposure, and is now a worldwide health concern. This study estimates the causal effects of exposure to lead in topsoil on cognitive ability among 5-year-old children. We draw on individual level data from...

Surface soil contamination has been long recognized as an important pathway of human lead exposure, and is now a worldwide health concern. This study estimates the causal effects of exposure to lead in topsoil on cognitive ability among 5-year-old children. We draw on individual level data from...