Towards System Optimum: Finding Optimal Routing Strategies in Time-Dependent Networks for Large-Scale Evacuation Problems

Evacuation planning crucially depends on good routing strategies. This article compares two different routing strategies in a multi-agent simulation of a large real-world evacuation scenario. The first approach approximates a Nash equilibrium, where every evacuee adopts an individually optimal routing strategy regardless of what this solution imposes on others. The second approach approximately minimizes the total travel time in the system, which requires to enforce cooperative behavior of the evacuees. Both approaches are analyzed in terms of the global evacuation dynamics and on a detailed geographic level.