Traffic assignment is used for infrastructure planning, based on metrics like total system travel time (TSTT), vehicle-miles traveled (VMT) and link or path flows. Algorithms for traffic assignment converge to an equilibrium solution over multiple iterations, but these metrics converge at different rates. Current guidance indicates that freeway link flows stabilize at a relative gap of roughly ${10}^{-4}$. This study generalizes this guidance by testing additional networks and metrics, in more experimental settings. Our results reveal that aggregate metrics (VMT and TSTT) stabilize earlier (relative gap ${10}^{-4}$) than link flows (relative gap ${10}^{-5}$), which in turn stabilize slightly before the set of most likely used paths and flows on these paths (relative gap ${10}^{-6}$). These results are stable across the TAPAS and Algorithm B methods for solving assignment. Our results also show strong linear correlations between alternative gap measures, allowing for the translation of stabilization results across other gap definitions as well.

交通分配用于基础设施规划，基于诸如总系统行驶时间（TSTT），行驶的车辆行驶里程（VMT）以及链接或路径流量之类的指标。用于流量分配的算法在多次迭代中收敛到均衡解，但是这些度量标准以不同的速率收敛。当前的指导意见表明，高速公路连接流的相对间隙稳定在大约${10}^{-4}$。本研究通过在更多实验性环境中测试其他网络和指标来概括本指南。我们的结果表明，总体指标（VMT和TSTT）较早稳定（相对差距）${10}^{-4}$）比链接流量（相对差距） ${10}^{-5}$），然后又在最可能使用的路径集和这些路径上流动之前相对稳定（相对间隙） ${10}^{-6}$）。这些结果在用于求解分配的TAPAS和算法B方法中是稳定的。我们的结果还表明，替代性缺口测度之间存在很强的线性相关性，也可以将稳定化结果转化为其他缺口定义。