CAREER: The Choice of Free vs. Priced for Transportation Systems

这个教师早期职业发展（Career）项目将告知是否对某些交通服务和设施的使用收费的共同政策选择，如计量停车或免费交通。这项研究将扩展道路和运输系统的模型，以考虑到增加或取消价格时产生的特殊考虑，例如，有和没有票价的公共汽车上车时间的差异。该项目还将通过模拟来考虑公平因素，以代表真实的社区，以捕捉政策对社会人口群体和收入水平的影响。该项目还将进行调查，以了解人们对替代定价策略的态度，并将阐明人们如何看待运输定价的公平性。此外，与研究相辅相成的教育任务将使土木工程专业的学生在认真思考实施实际政策方面获得经验，并使交通工程知识更容易获得。研究、教育和外展计划紧密结合，透过积极和互动的学习机会，进一步传播STEM的影响，以扩大STEM的参与。该项目的主要目标是追踪运输系统在零价格下表现出的不连续行为的后果。例如，当引入价格时，需求急剧下降，供应方和用户方的交易成本都会上升。这些和其他的不连续性将被插入到正式的运输模型中，在这个模型中，个体的选择相互影响，导致平衡。这些模型将应用于最优交通系统设计和交通分配问题，并研究如何最好地形式化广义成本函数中的零价格效应以及平衡的存在性和稳定性。详细的微观模拟将用于(i)验证从正式模型得出的结果，（ii）检查合理政策对合成人口的公平影响，以及（iii）检验关于次优价格的原始假设。考虑到交通外部性（如延误和污染）对交通流量是凸的，交通需求是凸的，以至于价格接近于零，该项目打算调查，在拥挤的道路上，即使引入较低的通行费和停车费，也能获得较高的、福利最大化的通行费和收费所获得的大量收益。一项调查研究将首次将新颖的研究方法扩展到运输定价领域，以系统地捕捉公众对经济政策的推理。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This Faculty Early Career Development (CAREER) project will inform common policy choices about whether to charge prices for the use of certain transportation services and facilities, such as metering parking or fare-free transit. The research will extend models of road and transit systems to account for special considerations that arise when prices are added or removed, e.g., the difference in bus boarding times with and without fares. The project will also consider equity factors through simulations calibrated to represent real communities, to capture policy impacts across sociodemographic groups and income levels. The project will also conduct surveys to understand people's attitudes towards alternative pricing strategies and will illuminate how people think about the fairness of transportation pricing. In addition, educational tasks complementary to the research will give civil engineering students experience in thinking rigorously about implementing real policies and make knowledge of transportation engineering more accessible. The research, education and outreach plans are tightly integrated, to further disseminate the impacts through active and interactive learning opportunities to broaden participation in STEM. The primary goal of the project is to trace the consequences of the discontinuous behavior that transportation systems exhibit at the zero price. For example, when prices are introduced, demand drops sharply and both provider- and user-side transaction costs arise. These and other discontinuities will be inserted into formal transportation models in which individuals' choices affect one another, leading to equilibrium. These models will be applied to problems of optimal transit system design and traffic assignment, with investigations into how best to formalize the Zero-Price Effect in generalized cost functions and the existence and stability of equilibria. Detailed microsimulations will be used to (i) validate results derived from the formal models, (ii) check the equity impacts of plausible policies over synthetic populations and (iii) test an original hypothesis about sub-optimal prices. The project intends to investigate if, given that traffic externalities such as delay and pollution are convex to traffic flow and traffic demand is convex to price near zero, introducing even low tolls and parking charges on congested roads can capture a substantial share of the benefits that higher, welfare-maximizing tolls and charges obtain. A survey study will extend novel research methods for systematically capturing the public's reasoning about economic policies into the domain of transportation pricing for the first time.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.