Martí Mestieri

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 hump-shaped evolution of manufacturing, and the rise of services over time. We estimate the demand system derived from the model using household-level data from the U.S. and India, as well as historical aggregate-level panel data for 39 countries during the postwar period. The estimated model parsimoniously accounts for the broad patterns of sectoral reallocation observed among rich, miracle and developing economies. Our estimates support the presence of strong nonhomotheticity across time, income levels...

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 consequences of technology. We prioritize in our discussion unified approaches to these three questions that are based on direct measures of technology.

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 been divergence in penetration rates. Using a model of adoption and growth, we show that these changes in the pattern of technology diffusion account for 80% of the Great Income Divergence between rich and poor countries since 1820.

Published: Diego Comin & Martí Mestieri, 2018. "If Technology Has Arrived Everywhere, Why Has Income Diverged?," American Economic Journal: Macroeconomics, vol 10(3), pages 137-178. citation courtesy of

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 adoption of firms, both at the extensive and the intensive margin. We use a data set of 15 technologies and 166 countries to estimate the intensive and extensive margin of adoption using the structural equations derived from our model. We find that the variability across countries in the intensive margin is higher than in the extensive margin. The cross country variation in intensive margin of adoption accounts for around 40% of the variation in income per capita.

Published: Technology Diffusion: Measurement, Causes and Consequences (with Diego Comin), Handbook of Economic Growth, vol. 2 .