Route Stability in Large-Scale Transportation Models

We present results from sensitivity analysis of a simulation model capturing the transportation system in a large urban setting. This system is a component of an agent-based simulation suite designed to model the effects and behaviors after a small-scale, nuclear detonation in the center of Washington D.C. In this paper we focus on how the ambient traffic density parameters affect the travel times and route choices of the individuals of the population in our model. These parameters are not easily estimated, particularly in the given context, and they directly influence travel times and routes which in turn impact the health and the behavior of the individuals and vice versa. This work is the first in a planned series of sensitivity analyses, with future extensions incorporating network structure and the detailed coupling with other system modules. Our sensitivity analysis shows that the ambient density parameters clearly impact travel times and route choices for broad ranges. The results indicate the existence of a threshold point beyond which the delay and changes in route are significant, showing that the appropriate range of density parameters needs to be carefully determined.