In traditional traffic equilibrium models, travelers typically rely on link flow information to estimate link/route costs. However, an often-overlooked aspect in prior research is that travelers can easily acquire information about the route choices of other travelers within the same OD pair. The presentation of route flow information, combined with the influence of travelers’ herd behavior, results in novel and intriguing conclusions distinct from conventional equilibrium models. Specifically, this study demonstrates that by considering the influence of the herd effect in route choice within the stochastic user equilibrium model, it is possible to address three critical problems that remain inadequately resolved in the literature: (1) The stability of stochastic user equilibrium (SUE) in the presence of route flow information. (2) The existence of meaningful link tolls capable of steering the SUE flow pattern toward system optimum (SO). (3) The design of a trial-and-error congestion pricing scheme with disequilibrium observed network flow patterns. To tackle these problems, we present a logit SUE flow evolution process with herd effect and propose a corresponding trial-and-error congestion pricing scheme. Rigorous proofs of related convergence theorems will be provided. The findings of this study support the assertion that “herd effect can offset travelers’ perception errors”, carrying significant policy implications for leveraging herd effect in the design of navigation software and congestion pricing strategies.

中文翻译：

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研究羊群效应对 Logit 随机用户均衡问题的影响


在传统的交通均衡模型中，旅行者通常依靠路段流量信息来估计路段/路线成本。然而，先前研究中经常被忽视的一个方面是，旅行者可以轻松获取同一 OD 对内其他旅行者的路线选择信息。路线流量信息的呈现，结合旅行者群体行为的影响，得出了不同于传统均衡模型的新颖且有趣的结论。具体来说，本研究表明，通过考虑随机用户均衡模型中的羊群效应对路线选择的影响，可以解决文献中尚未充分解决的三个关键问题：（1）随机用户均衡的稳定性（ SUE）存在路由流信息。 (2) 存在有意义的链路收费，能够将 SUE 流量模式引导至系统优化 (SO)。 (3)设计具有不平衡观测网络流量模式的试错拥塞定价方案。为了解决这些问题，我们提出了一种具有羊群效应的 Logit SUE 流演化过程，并提出了相应的试错拥塞定价方案。将提供相关收敛定理的严格证明。这项研究的结果支持了“羊群效应可以抵消旅行者的感知错误”的论点，对于在导航软件和拥堵定价策略的设计中利用羊群效应具有重要的政策意义。