Edgerton. 2023. Journal of Conflict Resolution
Researchers and policymakers have increasingly recognized foreign fighter mobilization as a national security threat to foreign states and domestic populations. Yet, scholars remain divided on the motivations of foreign combatants, arguing that fighters may be motivated by grievances, opportunity, or material incentives. The motivations of foreign fighters may be especially complex, as they are engaging in a conflict outside of their state. I analyze how historical and present-day group exclusionary policies and opportunity shape mobilization. To do so, I leverage novel data consisting of individual fighter data of Islamic State volunteers fighting in Iraq and Syria. In this article, I argue that foreign fighters are mobilized by group grievances over exclusionary and opportunity. Consistent with my theoretical framework, I find that a higher rate of Islamic State fighters come from areas where Sunni Muslims were denied access to political power and have greater state capacity.
Find the files and code here: https://github.com/jfedgerton/Edgerton-2023-JCR
Edgerton (2022) Network Science with Skyler J. Cranmer & Victor Finomore
Researchers have found that although external attacks, exogenous shocks, and node knockouts can disrupt networked systems, they rarely lead to the system's collapse. Although these processes are widely understood, most studies of how exogenous shocks affect networks rely on simulated or observational data. Thus, little is known about how groups of real individuals respond to external attacks. In this article, we employ an experimental design in which exogenous shocks, in the form of the unexpected removal of a teammate, are imposed on small teams of people who know each other. This allows us to causally identify the removed individual's contribution to the team structure, the effect that an individual had on those they were connected, and the effect of the node knockout on the team. At the team level, we find that node knockouts decrease overall internal team communication. At the individual level, we find that node knockouts cause the remaining influential players to become more influential, while the remaining peripheral players become more isolated within their team. In addition, we also find that node knockouts may have a nominal influence on team performance. These findings shed light on how teams respond and adapt to node knockouts.
Edgerton (2022) Social Networks
Previous research has attributed the motivations of suicide bombers to religious fervor, political engagement, and organizational strategic goals, among others. However, the processes underlying suicide bomber mobilization may also be related to primary and secondary socialization through family and peer network ties. To better understand the association between kin and peer ties and suicide bomber mobilization, I use a data set of 2,923 individual fighter-level observations of combatants for the Islamic State. These data include individual demographic data and if a combatant volunteered to be a suicide bomber. Through these data, I assess ideational, material, and the social origins of suicide bomber mobilization. I find that a one unit increase in kin or peer network ties is positively associated with a combatant's odds of volunteering to be a suicide bomber.
Edgerton (2022) Journal of Peace Research with Hollie Nyseth Nzitatira & Laura Frizzell
Recent studies of genocide have yielded varying estimates of the number and characteristics of people who engaged in violence. We address these disparities in estimates for one well-studied case: the 1994 genocide in Rwanda. Using novel data from Rwanda’s post-genocide gacaca courts, we provide updated estimates regarding participants. Specifically, we find that between 847,233 and 888,307 people participated in the genocide, with 181,280 to 190,113 people found guilty of only violent offenses, 618,164 to 654,152 individuals found guilty of only property crimes, and 44,042 to 47,789 individuals found guilty of both property and violent crimes. In total, we estimate that between 229,069 and 234,155 individuals were found guilty of a violent offense, including those who committed violent offenses as well as both violent and property offenses. These results align with past research, representing an important convergence of evidence regarding participation in this genocide. We also calculate specific characteristics of participants, finding that nearly 90% of all participants were men and that the median age for all participants was 34. Although most participants committed a single crime, between 215,124 and 222,522 people were found guilty of multiple crimes. Approximately 6% of people accounted for 25% of the property crimes, while 11% of people accounted for 25% of the violent crimes. These findings provide foundational information about one of the deadliest episodes of mass violence in the 20th century.
(Data and replication file embargoed until 2024)