We examine the economic impact of high-yielding crop varieties (HYVs) in developing countries 1960-2000. We use time variation in the development and diffusion of HYVs of 10 major crops, spatial variation in agro-climatically suitability for growing them, and a differences-in-differences...

We examine how the introduction of smallpox vaccination affected early-life mortality and fertility in Sweden during the first half of the 19th century. We demonstrate that parishes in counties with higher levels of smallpox mortality prior to the introduction of vaccination experienced a...