Economics of Air Travel: Network Effects, Congestion, and Scheduling Delays

航空旅行经济学：网络效应、拥堵和航班安排延误

• 批准号: 0214410
• 负责人: Todd Sinai
• 金额: --
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2007-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0214410&HistoricalAwards=false
• 关键词: Economics; Air; Travel; Network; Effects

In recent years, air traffic delays have become prevalent and are expected to increase in frequency and magnitude. This research will examine three principal issues: 1) What are the economic underpinnings of air traffic congestion? 2) Why do airlines choose not to adapt their schedules to fully account for predictable congestion? 3) What is the impact of expected travel time and scheduled travel time on fares? Since air traffic congestion is the proximate cause of longer travel times, the research begins by investigating its determinants. Two factors are possibly involved. One is the hub and spoke system used by most major carriers. Hubs enable passengers to connect to many destinations, creating network benefits that increase in the number of markets served from the hub. Congestion occurs when hub airlines bunch flights together in a short time period at hub airports, accepting longer average travel times in order to serve more cities and have shorter scheduled connections. The second factor in congestion is that airlines may not fully account for the fact that adding their own flights will lead to increased delays for other air carriers. Thus all airlines will have "too many" flights relative to what is socially optimal. Next, the project examines four reasons as to why airlines do not fully adjust their schedules for predictable increases in travel time, especially at hub airports, where hub airlines have especially poor on-time performance: i) competition with other carriers to report the shortest scheduled travel time may encourage obfuscation about accurate arrival times; ii) the uncertain nature of aircraft arrival times, combined with the constraint that an airline cannot schedule a departure until after the aircraft has been scheduled to arrive, makes it costly for an airline to add a large layover on the ground to buffer against delays; iii) hub airlines face additional incentives to have departure delays given that the hub carrier wants to retain the option to have flights that arrive earlier also depart earlier; iv) required minimum connection times at hubs encourage airlines to choose unrealistic schedules. The last stage of the research will examine how public policy could best address air traffic delays. This analysis will involve using fare data to determine how consumers value avoiding delays and the extent to which airlines are correctly taking the cost to consumers of delays into account when setting their schedules. This research will help design improved government policies with regard to air travel. The US Government can choose to tax additional flights and/or improve the transportation infrastructure. The results will help develop a tax that reduces inefficient congestion caused by airlines over-scheduling airports with fixed runway capacity while not discouraging the network benefits from operating a hub. At many airports, an ideal congestion tax might have a small impact on air traffic congestion since hub carriers may already internalize most of the costs of hubbing through a high local market share. Also, a careful examination of airline pricing and scheduling patterns allows for a more complete understanding of how competition affects the quality of private information and the economic value of consumer time. Such estimates provide a crucial, but often crudely estimated input in determining the optimal public investment in costly technology and infrastructure.

近年来，空中交通延误已变得普遍，并且预计频率和程度都会增加。 这项研究将探讨三个主要问题：1）空中交通拥堵的经济基础是什么？ 2) 为什么航空公司选择不调整航班时刻表以充分考虑可预测的拥堵情况？ 3）预计出行时间和预定出行时间对票价有何影响？ 由于空中交通拥堵是旅行时间延长的直接原因，因此该研究首先调查其决定因素。 可能涉及两个因素。 一种是大多数主要运营商使用的中心辐射系统。 枢纽使乘客能够连接到许多目的地，创造网络效益，增加枢纽服务的市场数量。 当枢纽航空公司在短时间内将航班在枢纽机场集中在一起，接受更长的平均旅行时间以服务更多的城市并缩短定期航班时，就会出现拥堵。 造成拥堵的第二个因素是，航空公司可能没有充分考虑到增加自己的航班将导致其他航空公司的延误增加的事实。 因此，相对于社会最佳状态，所有航空公司都会有“太多”航班。 接下来，该项目研究了航空公司没有针对可预测的旅行时间增加而全面调整航班时刻表的四个原因，特别是在枢纽机场，枢纽航空公司的准点率特别差： i) 与其他航空公司竞争以报告最短的航班时间预定的旅行时间可能会导致人们对准确的到达时间感到困惑； ii) 飞机到达时间的不确定性，加上航空公司在飞机预定到达后才能安排起飞的限制，使得航空公司在地面增加大量停留时间以缓冲延误的成本很高； iii) 鉴于枢纽航空公司希望保留让较早抵达的航班也较早起飞的选择权，因此枢纽航空公司面临着起飞延误的额外激励； iv) 枢纽的最短转机时间要求鼓励航空公司选择不切实际的时刻表。 研究的最后阶段将研究公共政策如何最好地解决空中交通延误问题。 该分析将涉及使用票价数据来确定消费者如何重视避免延误，以及航空公司在制定航班时刻表时正确考虑消费者延误成本的程度。这项研究将有助于设计改进的政府航空旅行政策。 美国政府可以选择对额外航班征税和/或改善交通基础设施。研究结果将有助于制定一项税收，减少因航空公司过度调度具有固定跑道容量的机场而造成的低效拥堵，同时不会阻碍运营枢纽带来的网络效益。 在许多机场，理想的拥堵税可能对空中交通拥堵产生很小的影响，因为枢纽航空公司可能已经通过较高的本地市场份额将大部分枢纽成本内部化。 此外，仔细检查航空公司的定价和航班安排模式可以更全面地了解竞争如何影响私人信息的质量和消费者时间的经济价值。这些估计为确定昂贵的技术和基础设施的最佳公共投资提供了关键但往往是粗略的估计输入。