Optimal tolls for multi-class traffic: Analytical formulations and policy implications (original) (raw)

The economics of truck toll lanes

2007

Truck-only lanes and tollways have been promoted as a way to combat road congestion, enhance safety and reduce pavement damage. This paper explores one aspect of truck lanes by considering whether there are advantages in separating cars and trucks. The benefits of vehicle separation are found to depend on several factors: the relative volumes of cars and trucks, the congestion delay and safety hazards that each type of vehicle imposes, values of travel time for cars and trucks, and lane capacity indivisibilities. The optimal assignment of vehicles to lanes can be supported using tolls that are differentiated by vehicle type and route. By contrast, lane access restrictions generally cannot support the optimum and may provide no benefit at all.

A comparative analysis of US toll policy

Transportation Research Part A: Policy and Practice, 2006

In the US, there is a long tradition of toll roads, beginning with the Lancaster Turnpike that was built at the end of the 18th century connecting Philadelphia and Lancaster. There are currently more than 300 toll facilities in the US, which is probably the largest number of toll facilities in the world. These facilities represent a wide range of conditions, from hypercongested facilities in large metropolitan areas such as New York City to toll highways in rural areas. The toll structures are equally diverse, ranging from multi-tier price structures with frequent user, carpool, and time of day discounts; to simpler structures in which the only differentiation is made on the basis of the number of axles per vehicle. The toll rates are typically set by the agencies that operate or own the toll facilities. The rules or formulas by which these tolls are determined are not generally available to the public, though it is safe to say that toll decisions are made taking into account technical considerations, as well as the all important criterion of political acceptability. However, data on toll rates and how they change by vehicle types and by some other attributes are readily available.

Economic Impacts of Introducing Tolls for Heavy-Goods Vehicles

Transportation Research Record: Journal of the Transportation Research Board

This paper focuses on the wider economic and environmental impacts of introducing or expanding road toll systems for heavy-goods vehicles in selected Spanish provinces and how these impacts compare with those of the German toll system. For this purpose, literature and statistical analyses are supported by applications of the European system dynamics model, ASTRA-EC, and stakeholder interviews. The main conclusions of this study are that positive as well as negative impacts of road pricing systems are often overestimated. Enhancing the environmental friendliness of truck fleets through differentiated tariffs and the generation of additional funds for roads and other investments are positive arguments for toll systems. However, the review of existing systems and transport model applications showed limited to negligible effects on the competitiveness of the transport sector, logistics patterns, modal shares, and wider economic impacts with the current charge levels in Germany and Spain...

Economic and Financial Feasibility of Truck Toll Lanes

Transportation Research Record: Journal of the Transportation Research Board, 2003

The economic and financial feasibility of heavy-truck toll lanes was analyzed. This research expanded the line of inquiry of previous researchers by analyzing toll lanes for exclusive use by heavy trucks (i.e., large size and capacity). Implementation of such a toll system was studied relative to productivity changes, toll-lane fees, users' travel time and vehicle operating cost savings, and impact on infrastructure costs. The economic benefits were estimated using the Highway Design and Maintenance Standards Model developed by the World Bank. The analyses, complemented with sensitivity analyses of key variables, indicate that heavy-truck lanes are economically and financially viable.

Tolled multi-class traffic equilibria and toll sensitivities

EURO Journal on Transportation and Logistics, 2015

We review properties of tolled equilibria in road networks, with users differing in their time values, and study corresponding sensitivities of equilibrium link flows w.r.t. tolls. Possible applications include modeling of individual travellers that have different trip purposes (e.g. work, business, leisure, etc.) and therefore perceive the relation between travel time and monetary cost in dissimilar ways. The typical objective is to reduce the total value of travel time (TVT) over all users. For first best congestion pricing, where all links in the network can be tolled, the solution can be internalized through marginal social cost (MSC) pricing. The MSC equilibrium typically has to be implemented through fixed tolls. The MSC as well as the fixed-toll equilibrium problems can be stated as optimization problems, which in general are convex in the fixed-toll case and non-convex in the MSC case. Thus, there may be several MSC equilibria. Second-best congestion pricing, where one only tolls a subset of the links, is much more complex, and equilibrium flows, times and TVT are not in general differentiable w.r.t. tolls in sub-routes used by several classes. For generic tolls, where the sets of shortest paths are stable, we show how to compute Jacobians (w.r.t positive tolls) of link flows and times as well as of the TVT. This can be used in descent schemes to find tolls that minimize the TVT at least locally. We further show that a condition of independent equilibrium cycles, Electronic supplementary material The online version of this article (

Comparison of Second-Best and Third-Best Tolling Schemes on a Road Network

Transportation Research Record, 2005

Much of the road pricing literature has focused on deriving second-best optimal tolls when only parts of a network can be tolled or tolling is constrained in other ways. A drawback of second-best tolling is that it requires extensive information on speed-flow curves and demand elasticities throughout the network. Such information is often not readily available, and errors in estimating key parameters could result in tolls that are nonoptimal or even welfare reducing. The purpose of this paper is to explore a simpler alternative policy, dubbed "no-queue" tolling, whereby time-varying tolls are imposed selectively on a road network with the objective of eliminating queuing on the tolled links. No-queue tolling is an example of third-best pricing because the effects of the tolls on other links are disregarded. To explore the merits of no-queue tolling, a dynamic traffic simulator (METROPOLIS) was used to compute no-queue tolls for individual links and cordon rings on a laboratory network. For comparison, second-best flat and time-varying tolls were also computed on the same sets of links. Two results stood out. First, even without accounting for the likely computational and acceptability advantages of no-queue tolling, it appeared to dominate flat tolling and performed relatively well compared to step tolling. Second, the benefits from no-queue tolling exhibited approximately constant returns with respect to the number of links that are tolled. This suggests that no-queue tolling could fruitfully be selectively implemented now, rather than waiting a decade or more for comprehensive road pricing to become feasible.

A Bi-Level Framework for Pricing of High-Occupancy Toll Lanes

TRANSPORT, 2014

As a freeway operational management strategy, High-Occupancy Toll (HOT) lanes have been deployed to manage the demand for High-Occupancy Vehicle (HOV) lanes by adjusting the tolls. By doing so, the capacity of freeways with such lanes can be used more efficiently. Periodically, setting the right amount of toll in accordance with the time-varying demand is a key to successful operation of HOT lanes; however, this is often difficult because travellers have heterogeneous willingness to pay for the toll and traffic conditions vary as the demand changes due to the imposition of tolls. This paper proposed an algorithm to determine the optimal level of toll for minimizing the total delay collectively spent by both HOVs and low-occupancy vehicles. Based on real-world traffic and survey data obtained from Gyungbu expressway in South Korea, a case study is presented to verify the applicability of the developed algorithm. The results from the case study show that the proactive dynamic pricing ...

Private toll roads: a dynamic equilibrium analysis

1997

In recent years there has been a surge of interest in private toll roads as an alternative to public free-access road infrastructure. Private toll roads have gained favour for a variety of reasons, including their potential to alleviate traffic congestion, shrinking public funds for road construction and maintenance, and growing acceptance of the user-pay principle. This paper takes the profitability of private toll roads as given, and focuses on their allocative efficiency. The model features one origin and one destination linked by two parallel routes that can differ in capacity and free-flow travel time. Congestion takes the form of queueing. Individuals decide whether to drive, and if so on which route and at what time. Three private ownership regimes are considered: a private road on one route and free access on the other route, competing private roads, and a mixed duopoly with a private road competing with a public toll road. The efficiency gain (measured by social surplus) in each regime is measured relative to the efficiency gain derived from applying first-best optimal tolls on both routes. Private toll roads are generally found to enhance efficiency. The efficiency gain is greater when tolls are varied over time to eliminate queueing, when competing routes are also tolled, when no private road has a dominant fraction of total capacity, and when a private road does not suffer a significant travel time disadvantage. Paradoxically, a mixed duopoly can be less efficient than a private duopoly. Price leadership by a public toll road operator avoids this possibility, although leadership typically yields little efficiency gain.

Evaluation Framework For Commercial Vehicle Responses To Congestion Pricing

California Partners For Advanced Transit and Highways, 1997

This report presents a short-run framework for analyzing the impacts of congestion pricing on commercial vehicles. The framework is based on microeconomics principles and past theoretical studies of congestion pricing. The relationship between value of time and the welfare gain/loss induced by using congestion pricing is identified. The social cost function and empirical demand and supply functions are also discussed.