The current study finds that societies which historically engaged in plough agriculture today have lower fertility. We argue, and provide ethnographic evidence, that the finding is explained by the fact that with plough agriculture, children, like women, are relatively less useful in the field....

We document an empirical relationship between the cross-country adoption of technologies and the degree of long-term historical relatedness between human populations. Historical relatedness is measured using genetic distance, a measure of the time since two populations' last common ancestors. We...

This summary of The Changing Body: Health, Nutrition, and Human Development in the Western World since 1700 (Cambridge) was prepared for presentation at the University of Alabama at Birmingham School of Public Health in March 2011. The book is built on the authors' work with 300 years of height...

Existing theories and empirical research on how innovation occurs largely assume that innovativeness is an inherent characteristic of the individual and that people with this innate ability select into jobs that require it. In this paper, we investigate whether people who do not self-select into...

Irving Berlin and Cole Porter were two of the great experimental songwriters of the Golden Era. They aimed to create songs that were clear and universal. Their ability to do this improved throughout much of their careers, as their skill in using language to create simple and poignant images...

We introduce a tractable model of endogenous growth in which the returns to innovation are determined by the technology adoption decisions of the users of new technologies. Technology adoption involves an implementation investment that determines the initial productivity of a new technology....

This chapter reviews academic research on the connections between agglomeration and innovation. We first describe the conceptual distinctions between invention and innovation. We then describe how these factors are frequently measured in the data and some resulting empirical regularities....

This paper provides the first systematic analysis of the link between economic, political, and social conditions and the global phenomenon of ISIS foreign fighters. We find that poor economic conditions do not drive participation in ISIS. In contrast, the number of ISIS foreign fighters is...