Toll Scheme Research Articles

Congestion and environmental toll schemes for the morning commute with heterogeneous users and parallel routes

We design a congestion and environmental toll (CET) scheme for the morning commute with heterogeneous users in a single OD network with parallel routes. The designed toll scheme relies upon the concept of marginal-cost pricing and is anonymous. The Henderson approach is used to model road congestion and the tolling problem to examine commuter's arrival time and route choice at the CET equilibrium (CETE). Linear interpolation is applied to approximate the emission cost function and the resulting CETE problem is formulated as an unconstrained optimization problem, which is solved by the modified Broyden-Fletcher-Goldfarb-Shanno (BFGS) method. Unlike the existing approach, this novel approach does not require that the arrival of each group of commuters at the destination at the equilibrium follows a predetermined order, and can handle non-monotone (emission) cost function. As two special cases, no-toll equilibrium (NTE) and the congestion toll equilibrium (CTE) are also examined, and the two resultant equilibrium problems are formulated and solved by the same approach. This approach is shown to be more efficient than the existing approach. Bi-level programming models are proposed to formulate the optimal congestion toll and CET design problems, in which the CTE and CETE problems are the corresponding lower level problem. These models are solved by the double BFGS method, which uses a classical BFGS method to solve the upper level model and the proposed BFGS method to solve the lower level model. Finally, numerical examples are provided to illustrate the properties of the models and the efficiency of the proposed solution algorithms.

Modelling and managing the integrated morning-evening commuting and parking patterns under the fully autonomous vehicle environment

This study is the first in the literature to analytically investigate the traffic dynamics of the integrated morning and evening commutes when daily trips are completed with autonomous vehicles (AVs). Given the parking locations of AVs resulting from the morning commute, firstly we analyse the evening commuting pattern, at which no traveller can reduce the individual travel cost given other AVs’ times of departures from the parking spaces. The equilibrium traffic pattern at the evening commute is then integrated with the morning commute, where equilibrium choices of departure time from home and parking location are derived and analysed. We then study the integrated morning-evening commuting pattern at the system optimum and develop the road tolling scheme to achieve the system optimum. Furthermore, this study analyses the optimal AV parking supply strategy to minimise the total system cost, which is comprised of the total social parking cost and the total daily travel cost under either user equilibrium or system optimum traffic pattern. We also illustrate the modelling insights through numerical studies regarding relationship among traffic efficiency, tolling schemes and AV parking supply plans. This study highlights the differences in daily commuting and parking patterns between the AV situation and the non-AV situation, and sheds light on how traffic and parking should be managed or planned in the future.

Selecting Compliant Agents for Opt-in Micro-Tolling

This paper examines the impact of tolls on social welfare in the context of a transportation network in which only a portion of the agents are subject to tolls. More specifically, this paper addresses the question: which subset of agents provides the most system benefit if they are compliant with an approximate marginal cost tolling scheme? Since previous work suggests this problem is NP-hard, we examine a heuristic approach. Our experimental results on three real-world traffic scenarios suggest that evaluating the marginal impact of a given agent serves as a particularly strong heuristic for selecting an agent to be compliant. Results from using this heuristic for selecting 7.6% of the agents to be compliant achieved an increase of up to 10.9% in social welfare over not tolling at all. The presented heuristic approach and conclusions can help practitioners target specific agents to participate in an opt-in tolling scheme.

Stabilisation strategy for unstable transport systems under general evolutionary dynamics

Stability of equilibria in transport systems has been discussed for decades. Even in deterministic cases, where stochasticity is ignored, stability is not a general property; a counterexample has been found in (within-day) dynamic traffic assignment problems. Instability can be a source of uncertainty of travel time and although pricing may stabilise an unstable transport system, pricing is not always acceptable to the public. This study aims to develop a pricing strategy that stabilises a transport system with minimum tolls. We show that with our stabilising pricing system tolls are bounded above and converge to zero when the error in estimation of a no-toll equilibrium converges to zero. We then show that the proposed toll scheme stabilises a wide range of evolutionary dynamics. We also propose a heuristic procedure to minimise the toll level. The procedure can also be viewed as a method of finding a possibly unstable equilibrium solution of a transport system. This suggests that, while we have not provided a rigorous proof, we may be able to find an equilibrium solution of any transport problem including problems which arise in dynamic traffic assignment (DTA); in these DTA cases, how to construct a solution algorithm that always converges to an equilibrium solution is still an open question. The methods proposed here will be extended so that they apply in more realistic behavioural settings in future work.

A cell-based dynamic congestion pricing scheme considering travel distance and time delay

This study introduces the dynamic congestion pricing (DCP) problem with the consideration of the actual travel distance and time delay (i.e. a joint distance and time-delay toll, JDTDT) in a dynamic network, which is more equitable and effective compared with existing tolling scheme. The system dynamics can be reflected in two aspects: (a) travelers' path choice decisions follow the dynamic user equilibrium principle and (b) the joint distance and time-delay toll takes a time-varying pattern. A multiperiod demand scheme is adopted during the entire modeling horizon and a bi-level programming model for the DCP is formulated to obtain the optimal toll value. Numerical results indicate that the percentage reductions of the minimum total system travel time in the dynamic JDTDT scheme are 6.28%, 4.30% and 7.45% compared to that obtained by the static joint JDTDT, the dynamic joint distance and time toll, and the dynamic pure distance toll, respectively.

Analysis of competitiveness development of Ukrainian products in the conditions of globalization

The article considers competition as a category, in which the state’s vigorous activity defines and implements a competitiveness strategy, establishes the «game rules» for market relations. The current state of Ukrainian products competitiveness in accordance with the Global Competitiveness Index in 2017–2018 is analyzed. For actualization an existing problem, the goal is set to analyze and identify the causes of goods, products and services low competitiveness, which produced in Ukraine, and to summarize the ways of their improvement in the context of modern globalization, transformation and European integration processes. The main advantages of national economy competitiveness ensuring are highlighted, but at the same time it is determined that a goods, which Ukraine exports, cannot adequately fill the country’s budget, that is, a raw materials have never been a commodity, which can save an economy. It was proposed to take as an example of the Poland experience, where the products manufacturing of European brands is carried out under tolling schemes. It has been established that the main factors, which hold back the competitiveness development of Ukrainian products in the context of globalization are the domestic market imperfection, the tax policy ineffectiveness, an incentives inhibition for innovation and investment activity, corruption, shadow economy, imperfection of public administration system in the framework of competitive advantages protecting of domestic commodity producers. The following ways of existing problem solving are proposed, namely: to determine the priorities of economic development and to direct resources for implementation of the most promising and efficient branches of national production, which have the proper competitive ability to enter an international market, to stabilize the tax system, financial and monetary policy; to improve of competition regulation system and stimulate innovation processes implementing in the economy.

A new design and evaluation approach for managed lanes from a sustainability perspective

This article presents a comprehensive framework that optimizes traffic management measures to reduce emissions and fuel consumption and evaluates their operating and secondary environmental impacts. A new managed lane strategy is presented that minimizes the total passenger travel time on the freeway. This managed lane focuses on simultaneously optimizing toll schemes on the high occupancy toll (HOT) lane and the operation of the general purpose (GP) lanes. With reduced congestion and thus reduced number of acceleration and deceleration events associated with stop-and-go traffic, fuel efficiency increases and emissions are reduced. PARAMICS microscopic traffic simulator, which considers the behavior of individual vehicles (e.g., acceleration, deceleration, and lane changing behavior) is used to collect traffic performance and emission data for estimating mobility and emissions measures (i.e., operating phase). While previous studies only focused on operating phase impact, this study uses a Leontief input-output (I-O) model to establish the financial flow between industries to capture the large-scale environmental impacts of HOT lane deployment (i.e., secondary impact). The core of the new evaluation approach lies in its capability to provide a more thorough assessment of the environmental impacts of traffic management schemes by quantifying the impacts associated with the interplay between the activities of various sectors and the transportation industry. The I-O model is utilized to assess the indirect impacts of induced demand generated from network improvements and evaluate the environmental impacts of HOT lane deployment in regional economies. The developed approach is applied to The City of Calgary. The results of the study show that the traditional approaches that only evaluate the operating phase impacts of transportation strategies considerably overestimate the reduction of greenhouse gas (GHG) emissions.

Impact of congestion pricing schemes on costs and emissions of commercial fleets in urban areas

AbstractAs urbanization increases, municipalities across the world have become aware of the negative impacts of road‐based transportation, which include traffic congestion and air pollution. As a result, several cities have introduced tolling schemes to discourage vehicles from entering the inner city. However, little research has been done to examine the impact of tolling schemes on the routing of commercial fleets, especially on the resulting costs and emissions. In this study, we investigate a vehicle routing problem considering different congestion charge schemes for several city types. We design comprehensive computational experiments to investigate whether different types of tolling schemes work in the way municipalities expect and what factors affect the performance of the congestion charge schemes. We compare the impact on a company's total costs, fuel usage (which drives emissions), and delivery tour plans. Our experimental results demonstrate that some congestion pricing schemes may even increase the emissions in the city center, and higher congestion charges may not necessarily lead to lower emissions.

Promoting social equity with cyclic tradable credits

This study manages the network mobility with link-based cyclic tradable credit scheme (CTCS) in a general transportation network. Different from most previous studies on tradable credit schemes, which always assume an independent periodic credit distribution scheme to maintain the circulation of the credits in the system with nonnegative credit charges, in our model the compensatory credits could be charged from (i.e. positive credit rate) or subsidized to (i.e. negative credit rate) the travelers. With the introduction of cyclic tradable credit scheme, we pursue three objectives: system optimization, social equity, and most importantly, credit internal cycling without periodic credit expiration and distribution. We formulate a minimization problem to solve for the scheme to fulfill the three objectives and discuss the existence of the solution via the dual problem. We prove that there is no negative cycle under the proposed CTCS, and when the origin-destination (OD) matrix of the network satisfies certain conditions, the Pareto-improving solution exists. However, for general networks with origins and destinations overlapping with each other, the solution may not always exist. Nevertheless, in contrast to several traditional toll schemes, the equity among the travelers from different OD pairs under the proposed CTCS is still improved. Numerical experiments are provided to demonstrate the existence/nonexistence of the CTCS under different situations and to compare the performances among different schemes.

Design of a heuristic environment-friendly road pricing scheme for traffic emission control under uncertainty

Road transportation is one of the main sources of atmospheric emissions in many countries and areas. Road pricing, is not only effective for urban transportation management, but also helpful in reducing the negative externalities caused by transportation. In this study, an inexact two-phase minimal emission programming (TMEP) model is proposed for design of the environment-friendly toll scheme with an acceptable road network performance. Through introduction of fuzzy stochastic programming, multiple uncertainties involved in vehicle emission evaluation are dealt with; the Traffic Performance Index (TPI) based constraints are incorporated to reflect the decision-maker's requirements for network congestion management. The solution method is proposed for generating the range of fuzzy stochastic objectives. An optimal toll scheme associated with the minimal emission based flow pattern is obtained through searching for a set of the best and the worst optimal solutions. A numerical experiment and a real-world road network in Beijing of China are used to illustrate the application of the developed method. In the case study, the toll scheme is obtained at the desired congestion level. The effects of emission and congestion abatement are analyzed under different policy scenarios. The proposed TMEP method can generate the toll scheme with obvious improvements in total emission reduction and congestion mitigation.

Cordon- or Link-Based Pricing: Environment-Oriented Toll Design Models Development and Application

This study focuses on an environment-friendly toll design problem, where an acceptable road network performance is promised. First, a Traffic Performance Index (TPI)-based evaluation method is developed to help identify the optimal congestion level and the management target of a transportation system. Second, environment-oriented cordon- and link-based road toll design models are respectively proposed through the use of bi-level programming. Both upper-level submodel objectives are to minimize gross revenue (the total collected toll minus the emissions treatment cost) under different pricing strategies. Both lower-level submodels quantify the user equilibrium (UE) condition under elastic demand. Moreover, the TPI-related constraints for the management requirements of the network performance are incorporated into the bi-level programming modeling framework, which can lead to 0–1 mixed integer bi-level nonlinear programming for toll design problems. Accordingly, a genetic algorithm-based heuristic searching method is proposed for the two pricing models. The proposed cordon- and link-based pricing models were then applied to a real-world road network in Beijing, China. The effects of the toll schemes generated from the two models were compared in terms of emissions reduction and congestion mitigation. In this study, it was indicated that a higher total collected toll may lead to more emissions and related treatment costs. Tradeoffs existed between the toll scheme, emissions reduction, and congestion mitigation.

Distance-Based Congestion Pricing with Day-to-Day Dynamic Traffic Flow Evolution Process

This paper studies the distance-based congestion pricing in a network considering the day-to-day dynamic traffic flow evolution process. It is well known that, after an implementation or adjustment of a new congestion toll scheme, the network environment will change and traffic flows will be nonequilibrium in the following days; thus it is not suitable to take the equilibrium-based indexes as the objective of the congestion toll. In the context of nonequilibrium state, prior research proposed a mini–max regret model to solve the distance-based congestion pricing problem in a network considering day-to-day dynamics. However, it is computationally demanding due to the calculation of minimal total travel cost for each day among the whole planning horizon. Therefore, in order to overcome the expensive computational burden problem and make the robust toll scheme more practical, we propose a new robust optimization model in this paper. The essence of this model, which is an extension of our prior work, is to optimize the worst condition among the whole planning period and ameliorate severe traffic congestions in some bad days. Firstly, a piecewise linear function is adopted to formulate the nonlinear distance toll, which can be encapsulated to a day-to-day dynamics context. A very clear and concise model named logit-type Markov adaptive learning model is then proposed to depict commuters’ day-to-day route choice behaviors. Finally, a robust optimization model which minimizes the maximum total travel cost among the whole planning horizon is formulated and a modified artificial bee colony algorithm is developed for the robust optimization model.

Stabilisation strategy for unstable transport systems under general evolutionary dynamics

Abstract Stability of equilibria in transport systems has been discussed for decades. Even in deterministic cases, where stochasticity is ignored, stability is not a general property; a counterexample has been found in (within-day) dynamic traffic assignment problems. Instability can be a source of uncertainty of travel time and although pricing may stabilise an unstable transport system, pricing is not always acceptable to the public. This study aims to develop a pricing strategy that stabilises a transport system with minimum tolls. We show that with our stabilising pricing system tolls are bounded above and converge to zero when the error in estimation of a no-toll equilibrium converges to zero. We then show that the proposed toll scheme stabilises a wide range of evolutionary dynamics. We also propose a heuristic procedure to minimise the toll level. The procedure can also be viewed as a method of finding a possibly unstable equilibrium solution of a transport system. This suggests that, while we have not provided a rigorous proof, we may be able to find an equilibrium solution of any transport problem including problems which arise in dynamic traffic assignment (DTA); in these DTA cases, how to construct a solution algorithm that always converges to an equilibrium solution is still an open question. The methods proposed here will be extended so that they apply in more realistic behavioural settings in future work.

Generated and induced traffic demand: Empirical evidence from a fixed link toll removal in Norway

Large infrastructure projects may significantly improve accessibility. Nevertheless, many such projects have toll schemes, and the total benefits may not be realised until the tolls have been removed. In response to toll removals, the traffic volumes on the corresponding infrastructure may change because of generated or induced traffic, the former being related to changes in travel patterns and the latter to new traffic. Predicting the consequences in advance can improve traffic forecasts and, thus, the assessment of infrastructure projects. Using the case of an island, this study analysed the traffic counts and a panel data survey of 132 respondents before and after toll removal. A mixed logit model was estimated to detect the role of the toll in users’ destination choice. The results showed that the toll did not affect destination choice significantly. Therefore, extra traffic may have resulted from route change, transportation mode change, or other potential structural changes. There were no clear indications of potential induced traffic, although this factor should be studied further.

Impact of Capacity Drop on Commuting Systems under Uncertainty

This paper analyzes the impact of capacity drop on commuters’ travel choice behaviors under uncertainty. For clarity, we assume that the capacity drop is triggered by the queue forming at the bottleneck under the hypercongestion circumstances, and the stochasticity of the drop could not be neglected. Considering the uncertainty of travel time, we establish a bottleneck model with commuters choosing their departure time according to the mean travel cost. From the proposed model, analytical solutions are achieved and therefore several properties are presented, including monotonicity of travel cost and departure rate, and the relationship between dispersion degree and length of peak period. To alleviate traffic congestion at the bottleneck and avoid capacity drop, we design a time-varying toll scheme and a step toll scheme. Evolution of queue length in equilibrium is discussed based on the Laih model. Numerical examples are also presented to demonstrate the established model and the effectiveness of the proposed toll schemes.

Congestion pricing policies: Design and assessment for the city of Rome, Italy

Congestion pricing is classified as a transportation demand management measure adopted to reduce impacts modern cities are suffering in terms of traffic congestion, road accidents and air and noise pollution. Such a measure allows linking road transport externalities directly to travelers producing them. The definition of proper tolling schemes enables this measure to act on demand short-term choices, forcing travellers to shift towards low impact road itineries (route diversion) and sustainable transport systems (modal diversion).This paper presents key findings in the design of pricing policies to a specific real size and complex case (city of Rome, Italy) addressing overall transport performances (on the multimodal network) and impacts (affecting the entire community), in a demand elastic context. Main contribution derives from equity matters dealt with in the impact assessment of pricing policies, so filling a gap not extensively studied in this field. Specifically, different tolling schemes have been defined from a quantitative (toll level) and spatial (city zones where pricing is implemented) viewpoint in order to guarantee equity aspects in the application of the measure: affected road users are limited to those travelling in city zones where the mass public transport network (metro and rail) is available; besides, the toll amount is related to the level of accessibility to public transport (whether only in origin/destination of the trip or in both).Results, evaluated adopting a simulation-based approach, are consistent with those obtained in other real world cases, and highlight that the adoption of a proper pricing policy in the city of Rome guarantees a demand diversion towards sustainable transport modes up to 25% for those zones directly involved by the pricing implementation; promising benefits have been observed even in a wider area, entire Province of Rome, not directly affected by the measure, in terms of reduction both of road users (up to 6%) and congestion costs (about 2%).

A Two-Layer Network Dynamic Congestion Pricing Based on Macroscopic Fundamental Diagram

Dynamic congestion pricing has attracted increasing attentions during the recent years. Nevertheless, limited research has been conducted to address the dynamic tolling scheme at the network level, such as to cooperatively manage two alternative networks with heterogeneous properties, e.g., the two-layer network consisting of both expressway and arterial network in the urban areas. Recently, the macroscopic fundamental diagram (MFD) developed by both field experiments and simulation tests illustrates a unimodal low-scatter relationship between the mean flow and density network widely, providing the network traffic state is roughly homogeneous. It reveals traffic flow properties at an aggregated level and sheds light on dynamic traffic management of a large network. This paper proposes a bilevel programming toll model, incorporating MFD to solve the unbalanced flow distribution problem within the two-layer transportation networks. The upper level model aims at minimizing the total travel time, while the lower level focuses on the MFD-based traffic assignment, which extends the link-based traffic assignment to network wide level. Genetic algorithm (GA) and the method of successive average were adopted for solving the proposed model, on which an online experimental platform was established using VISSIM, MATLAB, and Visual Studio software packages. The results of numerical studies demonstrate that the total travel time is decreased by imposing the dynamic toll, while the total travel time savings significantly outweigh the toll paid. Consequently, the proposed dynamic toll scheme is believed to be effective from both traffic and economic points of view.

An equilibrium analysis of commuter parking in the era of autonomous vehicles

This study is the first in the literature to model the joint equilibrium of departure time and parking location choices when commuters travel with autonomous vehicles (AVs). With AVs, walking from parking spaces to the work location is not needed. Instead, AVs will drop off the commuters at the workplace and then drive themselves to the parking spaces. In this context, the equilibrium departure/arrival profile is different from the literature with non-autonomous vehicles (non-AVs). Besides modeling the commuting equilibrium, this study further develops the first-best time-dependent congestion tolling scheme to achieve the system optimum. Also, a location-dependent parking pricing scheme is developed to replace the tolling scheme. Furthermore, this study discusses the optimal parking supply to minimize the total system cost (including both the travel cost and the social cost of parking supply) under either user equilibrium or system optimum traffic flow pattern. It is found that the optimal planning of parking can be different from the non-AV situation, since the vehicles can drive themselves to parking spaces that are further away from the city center and walking of commuters is avoided. This paper sheds light on future parking supply planning and traffic management.

Analysis of multimodal two-dimensional urban system equilibrium for cordon toll pricing and bus service design

This paper presents a multimodal urban system equilibrium model to address cordon toll pricing and bus service design issues in a two-dimensional monocentric city. Commuters are assumed to travel by auto or bus from their home locations to their workplace located in the city center through a ring-radial routing system. Auto users must pay tolls when passing through the cordons installed on the radial major roads. The multimodal two-dimensional urban system equilibrium is first formulated and its properties are analytically explored. A social welfare maximization model that simultaneously determines the optimal cordon toll location, toll level, bus service frequency and fare on each radial major road is then proposed. The effects of different tolling schemes (uniform and differential cordon-based, first-best, and no toll) on the multimodal urban system are also examined and compared.

Optimization of the freeway truck toll by weight policy, including external environmental costs

Abstract A policy for tolling trucks by weight has recently been implemented in China. However, the policy ignores the external environmental costs of heavy trucks. By referring to the German HGV toll policy, similar toll scheme has been implemented in China. This paper considers including the external environmental costs of heavy trucks on freeways in the Chinese toll system, similar to the German HGV toll policy. The truck toll by weight model is optimized to account for external costs of environmental pollution. A case study in Heilongjiang gives further insight into development of the toll by weight policy, which may contribute to development of sustainable transportation.