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In 2000, the average driver in US metropolitan areas endured 27 hours of traffic delays, a rise from 7 hours in 1980. In many other countries, traffic delays are considerably worse than in the United States, and in developing countries urban traffic congestion is increasing with alarming rapidity. For fifty years, economists have been advocating congestion pricing as the way to deal with urban traffic congestion; but today, even after some successes, congestion pricing is encountering considerable political resistance. The authors of Alleviating Urban Traffic Congestion advocate active consideration of more microscopic policies that attack the problem at the scale at which actual policy decisions are made. Microscopic models, rather than macroscopic models that are too simplified and too aggregated, they argue, will lead to the analysis of a wider and more creative range of policies, at least some of which should work well and be politically acceptable. After developing the themes of the book, the authors illustrate them by examining some areas of urban transport policy that have been neglected by the macroscopic approach. These include downtown parking policy, the encouragement of bicycling, the staggering of work hours by dominant employers, and the use by medium-sized cities of a "multimode" ticket that charges cars entering the city center a toll equal to the transit fare. The reorientation of urban transport analysis that they advocate will by no means eliminate traffic delays but should speed up the adoption of a richer, more flexible, and ultimately more effective set of policies to alleviate urban traffic congestion.

For several decades growth of traffic volumes has outstrippedinvestments inroad infrastructure. The result has been a relentless increase intrafficcongestion. This paper reviews the economic principles behindcongestionpricing in static and dynamic settings, which derive from thebenefits ofcharging travellers for the externalities they create. Specialattention ispaid to various complications that make simple textbook congestionpricingmodels of limited relevance, and dictate that congestion pricingschemes bestudied from the perspective of the theory of the second best. Thesecomplications include pricing in networks, heterogeneity of users,stochasticcongestion, interactions of the transport sector with the rest of theeconomy,and tolling on private roads. Also the implications of congestionpricing foroptimal road capacity are considered, and finally some explanationsfor thelongstanding social and political resistance to road pricing areoffered.

This book on road traffic congestion in cities and suburbs describes congestion problems and shows how they can be relieved. The first part (Chapters 1 - 3) shows how congestion reflects transportation technologies and settlement patterns. The second part (Chapters 4 - 13) describes the causes, characteristics, and consequences of congestion. The third part (Chapters 14 - 23) presents various relief strategies - including supply adaptation and demand mitigation - for nonrecurring and recurring congestion. The last part (Chapter 24) gives general guidelines for congestion relief and provides a general outlook for the future. The book will be useful for a wide audience - including students, practitioners and researchers in a variety of professional endeavors: traffic engineers, transportation planners, public transport specialists, city planners, public administrators, and private enterprises that depend on transportation for their activities.

This monograph explores the design of controllers that suppress oscillations and instabilities in congested traffic flow using PDE backstepping methods. The first part of the text is concerned with basic backstepping control of freeway traffic using the Aw-Rascle-Zhang (ARZ) second-order PDE model. It begins by illustrating a basic control problem suppressing traffic with stop-and-go oscillations downstream of ramp metering before turning to the more challenging case for traffic upstream of ramp metering. The authors demonstrate how to design state observers for the purpose of stabilization using output-feedback control. Experimental traffic data are then used to calibrate the ARZ model and validate the boundary observer design. Because large uncertainties may arise in traffic models, adaptive control and reinforcement learning methods are also explored in detail. Part II then extends the conventional ARZ model utilized until this point in order to address more complex traffic conditions: multi-lane traffic, multi-class traffic, networks of freeway segments, and driver use of routing apps. The final chapters demonstrate the use of the Lighthill-Whitham-Richards (LWR) first-order PDE model to regulate congestion in traffic flows and to optimize flow through a bottleneck. In order to make the text self-contained, an introduction to the PDE backstepping method for systems of coupled first-order hyperbolic PDEs is included. Traffic Congestion Control by PDE Backstepping is ideal for control theorists working on control of systems modeled by PDEs and for traffic engineers and applied scientists working on unsteady traffic flows. It will also be a valuable resource for researchers interested in boundary control of coupled systems of first-order hyperbolic PDEs.

This book on road traffic congestion in cities and suburbs describes congestion problems and shows how they can be relieved. The first part (Chapters 1 - 3) shows how congestion reflects transportation technologies and settlement patterns. The second part (Chapters 4 - 13) describes the causes, characteristics, and consequences of congestion. The third part (Chapters 14 - 23) presents various relief strategies - including supply adaptation and demand mitigation - for nonrecurring and recurring congestion. The last part (Chapter 24) gives general guidelines for congestion relief and provides a general outlook for the future. The book will be useful for a wide audience - including students, practitioners and researchers in a variety of professional endeavors: traffic engineers, transportation planners, public transport specialists, city planners, public administrators, and private enterprises that depend on transportation for their activities

AbstractThis paper uses a difference‐in‐differences strategy and an event‐study analysis to evaluate the effect of Uber entries on vehicle miles travelled in 346 US Metropolitan statistical areas between 2011 and 2017. Empirical results demonstrate that Uber entries have no significant effect on the total vehicle miles travelled in a city. However, Uber is found to decrease the vehicle miles travelled on highways but increase them on collector roads. All these effects come mainly from large metropolitan statistical areas. A simulation exercise suggests that Uber entries cause longer travel times if the share of travel time spent on collector roads is high.