ABSTRACT Considerable observational evidence indicates that travel time, averaged across a population, is stable at about an hour a day. This implies both an upper and a lower bound to time that can be expended on travel. The upper bound explains the self-limiting nature of road traffic congestion, as well as the difficulty experienced in attempting mitigation: the prospect of delays deters some road users, who are attracted back following interventions aimed at relieving congestion. The lower bound implies that time savings cannot be the main economic benefit of transport investment, which means that conventional transport economic appraisal is misleading. In reality, the main benefit for users is increased access to desired destinations, made possible by faster travel, which is the origin of induced traffic. Access is subject to saturation, consistent with the evidence of travel demand saturation. However, access is difficult to monetise for inclusion in cost–benefit analysis. Consequential uplift in real estate values may be a more practical way of estimating access benefits, which is relevant to the possibility of capturing part of such uplift to help fund transport investment that enhances such access.

中文翻译：

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时间限制和旅行行为

摘要 大量观察证据表明，平均而言，旅行时间稳定在每天约 1 小时。这意味着可以在旅行上花费的时间的上限和下限。上限解释了道路交通拥堵的自我限制性质，以及尝试缓解的困难：延误的前景阻止了一些道路使用者，他们在旨在缓解拥堵的干预措施后被吸引回来。下限意味着节省时间不能成为交通投资的主要经济效益，这意味着传统的交通经济评估具有误导性。实际上，用户的主要好处是通过更快的旅行来增加对所需目的地的访问，这是诱导流量的来源。访问受制于饱和，与旅行需求饱和的证据一致。然而，访问很难货币化以纳入成本效益分析。随之而来的房地产价值上涨可能是一种更实用的估算交通便利性的方法，这与获取部分此类上涨的可能性有关，以帮助为提高此类交通便利性的交通投资提供资金。