An Agent-Based Model of Protest Diffusion and Thresholds

• In Event: Pro-Democracy Protests

Abstract

This paper presents an agent-based model of protest diffusion and thresholds, developed from ethnographic interviews with dissidents in two repressive settings in the context of the Arab Spring (Egypt and Morocco; N=92). Previous qualitative analyses and related ethnographic interviews have established that dissidents in these settings are motivated by the behavior of others in their environment, combined with positive emotions of hope, courage, solidarity, and pride (Dornschneider 2019). This brings in the individual perspective to more context-based explanations of protest behavior. While a range of theories exists about the conditions under which protest is more likely, few explain the variation between individuals within the same context in terms of their protest behavior.

In this paper, we take the next step towards developing a new theory of protest behavior by investigating an agent-based model (Axtell 2000; Gilbert 2004; Epstein 2007; López-Paredes et al 2012), where the rules of behavior of the model are derived from the qualitative analyses (cf. Edmonds 2015). We apply the model to examine theories on protest diffusion and thresholds (Granovetter 1978), according to which protest decisions depend on the number of preceding protest decisions by others. Our application identifies four protest thresholds that complement the existing literature by specifying when 1) individuals begin to mobilize; 2) a critical mass shows up for protest; 3) mass protest occurs; and 4) protest declines.

Existing theories explain protest thresholds through preference falsification (Kuran 1991), according to which individuals hesitate to reveal their true preferences and join protest unless a sufficiently large number of protestors is observable, as well as the spiral of silence (Noelle-Neumann 1974), according to which individuals stay silent rather than voice their opinion to avoid social isolation. Our model adds to this literature by linking protest thresholds to emotions (Jasper 1998), which are a well-known, yet often ignored factor underlying individual protest behavior, especially in the diffusion literature. In our model, individuals are more likely to protest if emotion levels increase. Emotion levels in turn depend on knowledge of protest, interaction with protestors (online and offline), and state repression in the form of governmental violence, curfews, and state interventions on the online protest infrastructure.

Establishing the link between macro-level patterns and individual-level behavior is a perennial problem in social science (Elster 2007). This paper explores a model that links the micro-level decision making of individual potential protesters, with macro-level patterns of protest, their related emotions, and state repression. It therefore contributes to our theoretical understanding of protest diffusion and thresholds, while providing hypotheses for further investigation into our psychological and behavioral understanding of protest behavior.


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Authors

• Stephanie Dornschneider, University College Dublin

• Bruce Edmonds, Manchester Metropolitan University