​Working papers

Economies of Density and Congestion in Equipment Rental Markets, March 2026
​with Hester Zhang and Namrata Kala
revision requested Review of Economic Studies
[paper][online appendix]
[blog entry: IGC]
Rental markets are improving small-holder farmers' access to mechanization in developing countries, but the benefits depend heavily on market structure and how equipment is allocated during peak demand periods.  Efficient allocation favors large farms, due to scale diluting travel costs, and densely clustered small farms, which maximize machine utilization. We show that profit maximizing providers can improve allocations  comparably to a 20% increase in service capacity given market structure. 

Mechanizing Agriculture,  May 2022 
with Namrata Kala   
revision requested American Economic Review
out of the field (again) 
[paper][citation]
[slides][blog entries: econ that matters, VOXDev]
An RCT that subsidizes farmers access to productive capital. Mechanization generates labor savings in stages of production that are not mechanized, and labor savings for members of the household that are mostly engaged in worker supervision. We build a theory of mechanization decisions that depend on the incidence of moral hazard in labor markets, and show that welfare gains from mechanization depend on the incidence of those frictions.

The Organization of Work: Time Use and the Returns to Specialization, May 2026 New!
​with Claudia Macaluso and Pamela Medina-Quispe
[paper]
This paper examines how gains from specialization are shaped by the arrival of new technologies and how workers respond to the reorganization of production. We develop a theory in which firms choose how to partition job activities given technology, and workers allocate time across those partitions. More productive firms create more partitions, assign a larger share of activities to specialists, and exhibit greater task concentration within activities. We discipline the model using a novel firm-level survey from Lima, Peru, collected through a digital calendar-style platform. Returns to task specialization depend on firm size. In large firms, wages are approximately 70 log points higher at the 75th percentile of worker specialization, than for the average. In small firms, wages are statistically indistinguishable along worker specialization. We recover firms’ partition structures from workers’ joint time use, to calibrate our model and evaluate the response of  wage inequality and aggregate productivity to organizational shifts and worker time reallocation due to the arrival of technology.
​
On the Investment Network and Development,  September 2025 
with Lucia Casal
[paper]
[online appendix][slides][web with our data]
Our paper introduces the first harmonized measures of the investment network across the development spectrum and documents novel empirical regularities, including systematic changes in the network with development. We propose a simple theory linking these disparities, which are endogenous to the path of sectorial prices, to differences in income per capita across countries. We show that the elasticity of output to sectorial productivity depends on the investment network and is highest in the Construction sector in developing countries, and in the ICT and Service sector in developed countries. For our sample of 58 countries, we show that 28% of cross-country differences in income per capita can be accounted for by disparities in the investment network.These differences are twice as large as those estimated from standard development accounting exercises.

Capital-Embodied Structural Change, May 2024 
with Elisa Keller
[paper]
We show that differences in the price of investment relative to consumption vary systematically across sectors due to disparities in production equipment. In the postwar United States, these differences are quantitatively larger than sectoral TFP gaps. Capital-embodied technical change explains virtually all of the relative labor productivity gains in agriculture and a substantial share—about one-third—of those in services, both relative to manufacturing.               

Publications

Technology and the Task Content of Jobs across the Development Spectrum 
with Elisa Keller and Yongs Shin.       
WorldBank Economic Review, July 2023 
We harmonize two worker surveys to construct cross-country measures of task intensity across occupations. We document systematic differences in task intensity within occupations at different stages of development. We show that the decline in employment of routine intensive jobs is global, likely indicative of the global reaches of technical change.
     [paper][citation] 
     [data appendix][replication] 
     version commissioned by STEG [paper]
​
Occupational Exposure to Capital Embodied Technical Change  
with David Jaume ​and Elisa Keller
American Economic Review, June 2023
First measures of capital and of the elasticity of substitution between capital and labor in each occupation. Despite large measured disparities in the decline in the price of capital across occupations, heterogeneity in the elasticity of substitution drives the bulk of the observed labor reallocation and shift in occupational wage premium.
   [paper][citation] 
   [slides][online appendix][replication][web with our data]
​
Technical Change and the Demand for Talent 
with Elisa Keller
Journal of Monetary Economics,  July 2022.
Carnegie-Rochester-NYU Conference Series on Public Policy.  
To what extent has technical change mitigated or exacerbated barriers to labor market reallocation faced by different demographic groups? Overall, capital-embodied technical change mitigated the impact of labor market barriers for aggregate output per worker, but it fuelled wage inequality across gender and race. 
      [paper][citation]
      [slides] [replication][web with our data]
​
Capital Obsolescence and Agricultural Productivity  
with Elisa Keller                                                                                                                        
​The Quarterly Journal of Economics, February 2021.    
We build the first available measures of quality-adjusted capital stocks in agriculture across countries, exploiting prices and old and new equipment. We show that poor countries are not only less capital-intensive, but also have lower quality of capital than rich countries. Once adjusting for quality, differences in capital stocks account for almost twice as much of the agricultural labor productivity disparities across countries than previously thought. 
     [paper][citation]
     [slides][online appendix][replication][dataverse][erratum]
​     [ blog entry: focoeconomico]
​
Aggregate Fluctuations and the Industry Structure of the US Economy 
​European Economic Review,  October 2020.  
I document cyclical movements in the cost share of goods produced by investment oriented and goods oriented sectors, and show how they discipline heterogeneous elasticities of substitution in intermediate inputs across sectors. This heterogeneity increases shock amplification in the economy relative to a common elasticity framework.
​     [paper]​[citation] 
     [online appendix][replication]
​
 Who Quits Next? Firm Growth in Growing Economies  
 with  Emircan Yurdagul    
 Economic Inquiry, October 2018.
Differences in firm employment distributions are not informative of cross-country disparities in aggregate growth, while firm churning (as reflected in the age distribution) and average firm productivity are. We build a tractable theory of growth and firm dynamics and show that disparities in the probability of success in firm growth can explain two-thirds of the variation in growth. 
​       [paper] [citation]
​
Asymmetry, Complementarities and Federal Reserve Forecasts  
with Riccardo DiCecio, Ivana Komunjer, and Michael Owyang 
​Journal of Money, Credit and Banking, December 2018.
The literature has found that FED's forecast for unemployment, output and inflation are rationalizable but asymmetric along the cycle. We show that a a non-separable loss function induces symmetry in FEDs forecast for unemployment, but that there is systematic bias in the FED's forecasts for output and inflation. 
​     [paper][citation]
​

Selected work in progress

The Origins of Structural Transformation,  January 2025
with Mayara Felix and Kristina Manysheva
We study the micro features of the process of structural change, with a focus on the effect of firm entry into non-agriculture for farm entry and exit, technology adoption, and land and labor reallocation in the agriculture sector. We show that productivity improvements accompanied by labor demand shifts in non-agriculture are effective in transforming the agricultural sector. We propose a novel model of structural change that accommodates this rich micro structure and study the impact for structural change of  policies that target directly productivity improvements in agriculture versus those that target the non-agriculture sector.

Markup trends: Implications for embodied technology and the labor share,  November 2023 
with Gianluca Violante
We show that the entire increase in the aggregate markup since 1980s can be attributed to firms producing in equipment sectors and those in credit intermediation. After accounting for markups, ISTC is 0.5 percentage point faster than previously thought, accelerating from 2.41% to 2.92% each year on average. Markups can explain half of the observed decline in the labor share in equipment, and account for 1p.p. of the aggregate decline in the labor share. Sectors other-than equipment account for the bulk of the aggregate labor share dynamics, where there are virtually no markup trends.

Hibernating

​    Industry Dynamics, Investment and Uncertainty  September 2016
​         [paper][citation]
​         [online appendix]
​​

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Discussions