The Complexity of Turnout : An Agent - Based Simulation of Turnout Cascades

Using an agent-based simulation of electoral participation this paper examines the cascading effects of an exogenous increase in turnout. We simulate the voting behaviour of agents in a pool of 1,000 households with characteristics based on survey data and whose rules about interactions and behaviours are dictated by existing evidence. This model simulates the interplay between many factors important to understanding individual turnout. Unlike previous applications of agent-based modelling in political science, we adopt a descriptively complex rather than a simple model of behaviour. Thus factors affecting the turnout of agents include individual-level characteristics (e.g., socio-demographic characteristics, socialisation processes, habit and inertia, ‘rational behaviour’, political interest, social norms and values (e.g. civic duty), relational attributes and overlapping social networks (with a focus on political discussion and household influences), mobilisation (interpersonal and party based), and external shocks. The focus of the simulations is to gauge the cascade effects of election-day mobilisation based on exogenous GOTV initiatives on the turnout of individuals and others in their social networks. Experimenting with different levels of mobilisation allows us to examine the extent to which mobilisation spreads beyond the primary mobilisation target both across the population and whether it survives over time.