🤖 AI Summary
This study investigates how strategic interactions among migrating individuals—specifically in departure timing and route selection—drive collective group formation. Method: We formulate a bi-dimensional (time–path) decision model grounded in a Stackelberg game framework, incorporating heterogeneous individual travel costs to overcome the limitations of conventional unidimensional (time-only) modeling. Contribution/Results: Theoretical analysis uncovers a novel “neutral” strategy equilibrium beyond classical cooperation and competition; subgame-perfect equilibria exhibit multiplicity and heightened competitive intensity; and necessary and sufficient conditions for group formation are identified as synchronized arrival and path consistency. These findings extend evolutionary game theory’s applicability to collective behavior modeling and provide computationally tractable mechanistic insights and foundational principles for strategy design in real-world applications such as traffic flow optimization and emergency evacuation planning.
📝 Abstract
We present a Stackelberg game model to investigate how individuals make their decisions on timing and route selection. Group formation can naturally result from these decisions, but only when individuals arrive at the same time and choose the same route. Although motivated by bird migration, our model applies to scenarios such as traffic planning, disaster evacuation, and other animal movements. Early arrivals secure better territories, while traveling together enhances navigation accuracy, foraging efficiency, and energy efficiency. Longer or more difficult migration routes reduce predation risks but increase travel costs, such as higher elevations and scarce food resources. Our analysis reveals a richer set of subgame perfect equilibria (SPEs) and heightened competition, compared to earlier models focused only on timing. By incorporating individual differences in travel costs, our model introduces a "neutrality" state in addition to "cooperation" and "competition."