行人过马路决策中对所需时长的估计机制及其应用

Pedestrian safety has been a challenging issue in transportation safety, and it is important to understand pedestrian decision making process in order to improve their safety. Although an accurate road crossing decision depends both on the accurate estimation of time to arrival of approaching vehicles and the time needed to cross, previous studies have either explored pedestrian decision making error as a whole, or only focused on the time to arrival aspect, neglecting that pedestrians may not perform well in estimating cross time. Therefore, this proposal first evaluated two groups of pedestrians (the elderly and those distracted by mobile phones), who has been proven to be risky decision makers, on their ability to estimate cross time in Study 1. Aiming to understand potential bias in estimation, we proposed three experiments In Study 2 to distinguish two potential strategies, motor imagery simulation and computational strategy based on road width, hoping to uncover the underlying psychological mechanisms in cross time estimation. Then, based on the mechanisms discovered, two approaches, perceptual skill training and intelligent signal lights design, were proposed in Study 3 to improve pedestrians’ ability to estimate cross time more accurately and make better decisions. Overall, the project will theoretically deepen the understanding of pedestrian decision making error, guide future research on exploration of potential pedestrian risk factors, and help improve pedestrian safety in practice as well.

行人安全是道路交通安全中的难题，而明确行人过马路中的决策失误机制是提高行人安全的重要前提。行人做出是否过马路决策的能力同时取决于对车辆即将到达时间和对自身过马路所需时间估计的准确性，然而已有研究或从整体上研究行人决策失误的影响因素，或只关注了行人对车辆到达时间的估计过程，而忽略了行人可能在估计自身所需时长时存在偏差。本项目首先在研究1中评估了决策容易失误的高风险群体（老年行人、使用手机的行人）对过马路所需时长估计的准确性，并在研究2中采用三个实验探索了行人估计所需时长可能使用的线索和机制，重点区分基于运动表象的模拟策略和基于道路宽度的计算策略；并最终根据发现的时长估计机制在研究3中评估了通过行人知觉技能训练和智能信号灯设计方法提高行人时长估计和决策准确度的可行性。该项目不仅对于深入理解行人决策失误的原因和进一步寻找风险因素具有理论指导意义，也将对行人安全实践提供有效启示。

行人安全是道路交通安全中的难题，而明确行人过马路中的决策失误机制是提高行人安全的重要前提。行人做出是否过马路决策的能力同时取决于对车辆即将到达时间和对自身过马路所需时间估计的准确性，然而已有研究或从整体上研究行人决策失误的影响因素，或只关注了行人对车辆到达时间的估计过程，而忽略了行人可能在估计自身所需时长时存在偏差。..本项目首先在真实道路环境中评估了决策容易失误的高风险群体（老年行人、使用手机的行人）对过马路所需时长估计的准确性，发现不同于青年人，老年行人总是低估过马路的时长，尤其是在道路较宽时（四车道，六车道），而且由于低估程度非常大，即使其临时决定快速通过马路也无法抵消其低估偏差。进一步的分析表明，这种偏差并不是由于老年人较差的时间感知能力和运动表象能力导致的。与老年行人类似，使用手机的行人同样会低估过街时长，尤其是行人进行视觉相关任务（浏览文字等）时。虽然使用手机完成语音相关任务会降低行人速度，但行人会适应性增加其估计时长，故面临风险更小。研究还观察到行人在清空时期有大量违规行为，这种冒险决策可能和行人总是低估其过街所需时长有关。实验证明行人确实会高估特定剩余时间下完成过街的可能性。但是如果利用更合理的人机功能分配，由信号灯展示过街所需速度而非过街剩余时长，则可以大幅提高行人对过街可能性的判断准确性。..以上发现有助于理解行人决策失误的原因，为后续寻找行人风险因素提供指导，同时也提示道路交通安全管理中应尤其主要老年性人和使用手机完成视觉任务的行人，通过道路设计（如安全岛的设置）和信号灯的显示设计提高其对自身过街能力的评定准确性。