A Model of Social Norm Dynamics

Abstract

This paper introduces a deterministic model of social norm dynamics, with foundations in rational choice and methodological individualism. The model complements traditional game-theoretic approaches by addressing how individual decisions aggregate to form societal norms. While game theory provides important insights into coordination and cooperation, insofar as it is formalized, it often focuses on static outcomes and small-scale situations. In contrast, the proposed model scales effectively and features temporal dynamics of norm development and stabilization. This utility-theory approach incorporates three primary forces to explain agent-level behavior: native preference, social influence, and habit formation. Native preference represents intrinsic and heterogeneous motivations, which ensure some behavioral variety, even in environments characterized by high conformity. Social influence reflects the pressure to change that individuals feel from observing the behaviors of others, which drives conformity. Habit formation stabilizes behavior over time, encouraging actions consistent with past decisions. These forces interact to explain how individuals embedded in a social environment contribute to the emergence of macrosocial patterns. A key feature of this model is the concept of "support," which captures the degree to which chosen behaviors align with a given social norm. Importantly, support is not just a measure of a single behavior; it reflects the interrelation between various behaviors with respect to the norm. A norm is formally defined in the context of this model, and simulated environments are presented that demonstrate how changes in network structure affect the overall level of conformity to a norm within a population. While the work presented here is theoretical, the model provides a foundation for future empirical exploration and contributes to ongoing discussions on social norms.