Job Market Paper: Who Rescues? Who Betrays? The Fate of Cross-Group Friendships in Wartime

Do cross-ethnic social ties completely cease to matter once the bullets start flying? Based on a new survey on survivors of the 1992-5 Bosnian War, I find that cross-ethnic assistance was not only widespread but highly correlated with the number of outgroup friendships pre-war. In contrast, help from complete strangers and active betrayal by close friends appear to have been rare. Drawing on over 140 interviews, I show how cross-ethnic social networks were used to channel assistance to those in need from those with the resources and position to provide it. Most people, it appears, were willing to help not only friends but even friends-of-friends and acquaintances, provided the risk was not too great. The result was widespread assistance that was helpful but generally not life-saving. Finally, integrating census data and a comprehensive database of wartime fatalities with my survey results, I argue that intermarriage and residential integration led to more assistance but had little effect on the overall death toll. Policymakers should, therefore, continue to promote cross-ethnic social networks as a means to mitigate non-fatal suffering during mass violence, but should not rely on them as a means to prevent violence outright.

Stuck in the Mud: Roads, Rain and Repression

(with Philipp Hunziker and Carl Müller-Crepon)

Does government access to remote regions encourage or hinder armed conflict? Road networks have long been an essential tool of state-building for projecting state power from the capital into the hinterlands.  Such power could potentially deter would-be rebels and stamp out clashes between local ethnic groups or it could lead to increased rebel capacity and more state-initiated violence. To answer these questions, we use quasi-random variation in heavy rainfall as an instrument for whether certain roads are temporarily removed from the network due to flooding. We then examine whether outlying areas rendered-temporarily inaccessible experience an uptick in violence. Our evidence comes from a newly-digitized historical dataset of African road networks extracted from Michelin road maps using deep-learning neural networks, satellite-based weather data, and a high-resolution conflict event dataset. Based on our results, we expect to be able to highlight those parts of the African road network where improvements would foster state reach the most.

The Impact of Domestics Terror Attacks on Attitudes Towards Immigrants

(with William Minozzi, Michael Neblo, and David Lazer)

How do close encounters with terrorism shape political sentiments? We examine longitudinal data for a group of students, a subset of whom lived through a terrorist attack by a Muslim immigrant, and compare their support for immigration before and after to that of their peers.  Contrary to the existing literature, we find an asymmetric reaction across the political spectrum: while moderate and conservative students increase their hostility to immigration, liberal students do not register any shift in opinion. This effect is not explained by personality traits such as anxiety, nor by prior views on immigration, nor is it accompanied by a shift in ideology, authoritarianism, or other political attitudes.  We argue that this heterogeneous yet limited effect is driven by participants’ subconscious efforts to frame the attacks within an existing narrative. For moderates and conservatives, the incident activates confirmation bias reinforcing their previous fears. Liberals, in contrast, experience cognitive dissonance and write it off as irrelevant or fit it into some other cognitive frame commensurate with their political identity. We conclude by reflecting on the how future events of this kind may influence the American electorate.

Photo: Aftermath of terror attack at Ohio State University. Credit: Blervis (Wikipedia)


Segregation and Coexistance in Informal Settlements

In the summer of 2016 I spent eight weeks in Kampala, Uganda interviewing and surveying residents in slums about their friendship, secret-sharing, and money-borrowing networks.  My preliminary results suggest that migrants from the North of Uganda are more likely to segregate themselves along ethnic lines, while those hailing from the center are more likely to form cross-ethnic ties.  I am currently exploring to what degree this homophily (self-segregation) can be attributed to war-related trauma from internally displaced persons (IDPs) who fled the conflict between the Ugandan military and the Lord's Resistance Army.  In addition, there is evidence to suggest that residents who have spent more time in the diverse environment of Kampala are more likely to be open to friendships with other tribes. Hence, a slum, in spite of crime, unemployment, and conflict over property rights, can potentially serve as a breeding ground for coexistence.


  • An online randomized control trial to increase voter turnout through student friendship networks

  • An analysis of racial and gender bias in the interdisciplinary field of network science

  • A randomized control trial in rural India looking at how family planning interventions can multiply their impact by taking advantage of pre-existing friendships and kinship ties

Contact: simonson.m [at] northeastern [dot] edu