Working Papers

Drivers of Concentration: The Roles of Trade Access, Structural Transformation, and Local Fundamentals (Job Market Paper)

What factors determine the degree of spatial concentration of a country's population? I investigate the drivers of concentration by adding non-homothetic preferences to a modern quantitative spatial model, obtaining a two-sector spatial model in which concentration depends on trade networks, structural transformation, and location-specific fundamentals (i.e. productivities and amenities). The model delivers an analytical expression decomposing changes in spatial concentration into separate terms that reflect the roles of these three forces. I then bring the model to the data in two steps: first, estimate gravity trade equations to recover year- and sector-specific trade-cost matrices; then, I "calibrate" the model to the 2005 global economy (featuring 1611 locations across 192 countries) by finding local fundamentals that rationalize population and income data given the equilibrium equations. I use this calibrated model for counterfactual exercises that clarify the role of trade access on spatial concentration. Results indicate that increasing access to foreign markets reduces concentration in most countries. Finally, I use the model-implied decomposition equation to disentangle the roles of structural transformation, differential trade access, and local fundamentals in accounting for the observed 1990-2015 changes in concentration for 44 countries. The bulk of the variation is explained by local fundamentals, with only 1% accounted for by differential trade access and structural transformation.

Work in Progress

Measuring Non-Tariff Barriers


Combining Pre-School Teacher Training with Parenting Education: A Cluster-Randomized Controlled Trial (with Berk Özler, Lia C.H. Fernald, Patricia Kariger, Christin McConnell, Michelle Neuman), Journal of Development Economics, 2018, 133(C), 448-467.

We used a randomized, controlled study to evaluate a government program in Malawi, which aimed to support child development by improving quality in community-based, informal preschools through teacher training, financial incentives, and group-based parenting support. Children in the integrated intervention arm (teacher training and parenting) had significantly higher scores in assessments of language and socio-emotional development than children in preschools receiving teacher training alone at the 18-month follow-up. There were significant improvements in classroom organization and teacher behavior at the preschools in the teacher-training only arm, but these did not translate into improved child outcomes at 18 months. We found no effects of any intervention on child assessments at the 36-month follow-up. Our findings suggest that, in resource-poor settings with informal preschools, programs that integrate parenting support with preschools may be more (cost-) effective for improving child outcomes than programs focusing simply on improving classroom quality.