This chapter discusses different approaches pursued to explore three broad questions related to technology diffusion: what general patterns characterize the diffusion of technologies, and how have they changed over time; what are the key drivers of technology, and what are the macroeconomic...

We use new data on manufacturing in Canada to quantify the impact of globalization on the growth and composition of industrialization in the second half of the nineteenth century. We find that industries and regions more exposed to international trade experienced faster growth. Consistent with...

We examine the generalizability of internally valid estimates of causal effects in a fixed population over time when that population is subject to aggregate shocks. This temporal external validity is shown to depend upon the distribution of the aggregate shocks and the interaction between these...

We argue that political distribution risk is an important driver of aggregate fluctuations. To that end, we document significant changes in the capital share after large political events, such as political realignments, modifications in collective bargaining rules, or the end of dictatorships,...

This paper specifies a general set of conditions under which the impacts of a policy can be identified using data generated under a different policy regime. We show that some of the policy impacts can be identified under relatively weak conditions on the data and structure of a model. Based on...

Randomized controlled trials are increasingly used to evaluate policies. How can we make these experiments as useful as possible for policy purposes? We argue greater use should be made of experiments that identify behavioral mechanisms that are central to clearly specified policy questions,...

This paper studies optimal lockdown policies in a dynamic economy without government commitment. A lockdown imposes a cap on labor supply, which lowers economic output but improves health prospects. A government would like to commit to limit the extent of future lockdowns in order to increase...

We study the role of foreign-born workers in the growth of employment in STEM occupations since 1980. Given the importance of employment in these fields for research and innovation, we consider their role in a model featuring endogenous non-routine-biased technical change. We use this model to...

Digital technology is the representation of information in bits. This technology has reduced the cost of storage, computation, and transmission of data. Research on digital economics examines whether and how digital technology changes economic activity. In this review, we emphasize the reduction...

Technological change, from the advent of robots to expanded trade opportunities, tends to create winners and losers. How should government policy respond? And how should the overall welfare impact of technological change on society be valued? We provide a general theory of optimal technology...