Sebastian Hohmann

I am an economist and data scientist.

From September 2018 to February 2020, I was Assistant Professor of Economics at Stockholm School of Economics SITE.

I did my PhD at London Business School.
Curriculum Vitae
Contact:
sebas [dot] hohmann [at] gmail [dot] com
Github
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Research


Working Papers

  • Natural Resources, Trade, and Structural Transformation in Africa
    I combine georeferenced data on mining and oil endowments with satellite-images of land use and census data on 112 million individuals from 2,700 regions in 23 countries to show that resource extraction and international trade have fuelled Africa's recent structural transformation. In the first part of my analysis, I document that both increases in the values of regional natural resource endowments, induced by global price shocks, as well as a U.S. policy change, lowering tariffs on African imports, which affected regions close to ports more strongly, lead to reallocations away from agriculture towards services. The natural resource and trade shocks are re-enforcing in their effect on agriculture and services, but neither crowds out manufacturing employment, which even expands in response to the trade shock. In the second part of the analysis, I develop and then calibrate a quantitative multi-region multi-industry trade model of structural transformation. There are two forces at play. Increases of local incomes in mining regions increase the demand for non-tradables whereas reduced external trade costs, by lowering the prices of tradable goods, favour locations better connected to international markets. I find the correlation between model-predicted and observed labour share changes to be around 55 percent. Which of the two forces dominate in explaining observed structural transformation depends on the spatial configuration of location-specific access to international markets and natural resource advantages. The analysis concludes with counterfactual simulations of the structural change implications of larger resource booms and autarky.

  • Intergenerational Mobility in Africa Previous NBER WP 25534, CEPR DP 15785
    with Alberto Alesina, Stelios Michalopoulos, and Elias Papaioannou
    Media coverage: The Economist VOXEU podcast
    We examine intergenerational mobility (IM) in educational attainment in Africa since independence using census data. First, we map IM across 27 countries and more than 2,800 regions, documenting wide cross-country and especially within-country heterogeneity. Inertia looms large as differences in the literacy of the old generation explain about half of the observed spatial disparities in IM. The rural-urban divide is substantial. Though conspicuous in some countries, there is no evidence of systematic gender gaps in IM. Second, we characterize the geography of IM, finding that colonial investments in railroads and Christian missions, as well as proximity to capitals and the coastline are the strongest correlates. Third, we ask whether the differences in mobility across regions reflect spatial sorting or the independent role of the former. To isolate the two, we focus on children whose families moved when they were young. Comparing siblings, looking at moves triggered by displacement shocks, and using historical migrations to predict moving-families’ destinations, we establish that, while selection is considerable, regional exposure effects are at play. An extra year spent in a high-mobility region before the age of 12 (and after 5) significantly raises the likelihood for children of uneducated parents to complete primary school. Overall, the evidence suggests that geographic and historical factors laid the seeds for spatial disparities in IM that are cemented by sorting and the independent impact of regions.

  • Ethnic and Religious Intergenerational Mobility in Africa
    with Alberto Alesina, Stelios Michalopoulos, and Elias Papaioannou
    We investigate the evolution of inequality and intergenerational mobility in educational attainment across ethnic and religious lines in Africa. Using census data covering more than 70 million people in 19 countries we document the following regularities. (1) There are large differences in intergenerational mobility both across and within countries across cultural groups. Most broadly, Christians are more mobile than Muslims who are more mobile than people following traditional religions. (2) The average country-wide education level of the group in the generation of individuals' parents is a strong predictor of grouplevel mobility in that more mobile groups also were previously more educated. This holds both across religions and ethnicities, within ethnicities controlling for religion and vice versa, as well as for two individuals from different groups growing up in the same region within a country. (3) Considering a range of variables, we find some evidence that mobility correlates negatively with discrimination in the political arena post indepdence, and that mobility is higher for groups that historically derived most of their subsistence from agriculture as opposed to pastoralism.

  • The Employment Effects of Ethnic Politics
    with Francesco Amodio and Giorgio Chiovelli
    This paper studies the labor market consequences of ethnic politics in African democracies. We combine geo-referenced data from 15 countries, 32 parliamentary elections, 62 political parties, 243 ethnic groups, 2,200 electoral constituencies, and 400,000 individuals. We implement a regression discontinuity design that compares individuals from ethnicities connected to parties at the margin of electing a local representative in the national parliament. We find that having a local ethnic politician in parliament increases the likelihood of being employed by 2-3 percentage points. We hypothesize that this effect originates from strategic interactions between ethnic politicians and traditional leaders, the latter retaining the power to allocate land and agricultural jobs in exchange for votes. The available evidence supports this hypothesis. First, the employment effect is concentrated in the historical homelands of ethnicities with strong pre-colonial institutions. Second, individuals from connected ethnicities are more likely to be employed in agriculture, and in those countries where customary land tenure is officially recognized by national legislation. Third, they are also more likely to identify traditional leaders as partisan, and as being mainly responsible for the allocation of land. Evidence shows that ethnic politics shapes the distribution of productive resources across sectors and ethnic groups.

Work in Progress

  • Diplomatic Relations and Private Investment
    with Ryan Lewis
  • Internal Migration in Africa: Evidence from Census data

Teaching


GIS Methods Course