Agent-Based Modelling

Excluding environmental phenomena, the emergent complexity frequently observed in real-world dynamics often stems from the autonomous nature of the individuals, communities, and organisational entities that make up human societies. These distinct entities, whether individual or group-based, operate guided by their own values, beliefs, and decision-making capabilities, with varying levels of independence from any centralised governing authorities present. Conventionally, many models of society assume that individuals and organisational entities behave in a greedy fashion \cite{medema2009hesitant}. However, there are many examples where, despite the lack of any centralised authority, real-world entities remain largely regulated in their behaviour (such as may be seen from the cooperation observed in the global Air Transportation System), contrary to what might be expected when combining multiple greedy entities. Such examples make it apparent that in reality individual or group-based entities demonstrate reactive, pro-active, cooperative, and social traits. Building on these observed behaviours, Agent-Based Modelling (ABM) is one of the few methods available to social studies for exploring this level of dynamic and stochastic complexity, by directly considering the interaction of human-centric traits within a modelled group of entities. Several fundamental features are commonly agreed on as characteristics of agents, as summarised in Table \ref{table:agent_characteristics} \cite{Macal_2006}. Of these, the most critical condition is that any agent should be capable of making independent decisions, ensuring active, rather than passive, behavioural characteristics.