I discuss the concept and empirical importance of international technology diffusion from the point of view of recent work on endogenous technological change. In this literature, technology is viewed as technological knowledge. I first review the major concepts, and how international technology...

Interpreting individual heterogeneity in terms of probability theory has proved powerful in connecting behaviour at the individual and aggregate levels. Returning to Ricardo's focus on comparative efficiency as a basis for international trade, much recent quantitative equilibrium modeling of the...

Two centuries ago, in most countries around the world, women were unable to vote, had no say over their own children or property, and could not obtain a divorce. Women have gradually gained rights in many areas of life, and this legal expansion has been closely intertwined with economic...

We study the climate as a determinant of religious belief. People believe in the divine when religious authorities (the "church") can credibly intervene in nature on their behalf. We present a model in which nature sets the pattern of rainfall over time and the church chooses when optimally to...

This paper and its companion study, Fehr, Jokisch, and Kotlikoff (2004), develop a three-region dynamic general equilibrium life-cycle model to analyze general and skill-specific immigration policy during the demographic transition. The three regions are the U.S., Japan, and the EU. Immigration...

Among countries colonized by European powers during the past 500 years those that were relatively rich in 1500 are now relatively poor. We document this reversal using data on urbanization patterns and population density, which, we argue, proxy for economic prosperity. This reversal is...

How do communication costs affect the production of new ideas and inventions? To answer this question, we study the introduction of the Uniform Penny Post in Great Britain in 1840. This reform replaced the previous system of expensive distance-based postage fees with a uniform low rate of one...

This paper uses a large language model to develop an ex-ante measure of the commercial potential of scientific findings. In addition to validating the measure against the typical holdout sample, we validate it externally against 1.) the progression of scientific findings through a major...

Understanding factors affecting the direction of innovation is a central aim of research in the economics of innovation. Progress on this topic has been inhibited by difficulties in measuring distance and movement in knowledge space. We describe a methodology that infers the mapping of the...

This paper considers the labor market and distributional implications of a scenario of ever-more-intelligent autonomous machines that substitute for human labor and drive down wages. We lay out three concerns arising from such a scenario and evaluate recent predictions and objections to these...