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 study the lags with which new technologies are adopted across countries, and their long-run penetration rates once they are adopted. Using data from the last two centuries, we document two new facts: there has been convergence in adoption lags between rich and poor countries, while there has...

We present a tractable model for the analysis of the relationship between economic growth and the intensive and extensive margins of technology adoption. At the aggregate level, our model is isomorphic to a neoclassical growth model. The microeconomic underpinnings of growth come from technology...

We present a new multi-sector growth model that features nonhomothetic, constant-elasticity-of-substitution preferences, and accommodates long-run demand and supply drivers of structural change for an arbitrary number of sectors. The model is consistent with the decline in agriculture, the...

We propose a mechanism for labor-market polarization based on the nonhomotheticity of demand that we call the income-driven channel. Our mechanism builds on a novel empirical fact: expenditure elasticities and production intensities in low- and high-skill occupations are positively correlated...

Dynamic models of structural transformation are often non-stationary, precluding balanced growth path (BGP) analysis. We develop a generalization of the BGP concept that we call a Stable Transformation Path (STraP). The STraP characterizes the medium-term dynamics of the economy in a turnpike...

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....

We present evidence on the differences in the intensity with which ten major technologies are used in 185 countries across the world. We do so by calculating how many years ago these technologies were used in the U.S. at the same intensity as they are used in the countries in our sample. We...

We assemble a dataset on technology adoption in 1000 B.C., 0 A.D., and 1500 A.D. for the predecessors to today's nation states. We find that this very old history of technology adoption is surprisingly significant for today's national development outcomes. Although our strongest results are for...

Can a country grow faster by saving more? We address this question both theoretically and empirically. In our model, growth results from innovations that allow local sectors to catch up with the frontier technology. In relatively poor countries, catching up with the frontier requires the...