Mechanisms of Inequality: Models, Experiments, and Consequences

How do micro-level behaviors aggregate into stable macro-level inequalities? This session brings together approaches that treat this question as their central explanatory target. Beyond documenting which individual attributes are associated with unequal outcomes, the modeling tradition asks what set of behavioral rules and interaction structures is sufficient to generate observed patterns of stratification.

We invite contributions that specify mechanisms of inequality generation: cumulative advantage and Matthew effects, sorting and matching, homophilous tie formation, network-based diffusion of resources and opportunities, segregation dynamics, and the coevolution of behavior and structure. We welcome a deliberately pluralist methodological repertoire. Agent-based and mathematical models can make these feedback loops explicit and discipline them against empirical targets. Behavioral and field experiments can isolate the micro-foundations such models assume, testing whether posited mechanisms actually operate. Network methods and new data sources—digital traces, web platforms, administrative linkages—extend observation to relational processes at scales and resolutions that complement established designs.

Specifying mechanisms also clarifies the consequences of inequality for collective life. The same reasoning that explains how stratification emerges can show how, in turn, it reshapes the conditions for cooperation—altering the incentives and norms that sustain collective action—and the dynamics of opinion and polarization.

By foregrounding the micro-macro transition itself, the session aims to consolidate an explanatory, generative agenda for inequality research—one centered on the interacting processes that bring stratification into being and sustain it, not its cross-sectional shape alone.