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on Transport Economics |
| By: | Shian Dai; Liqiang Yu; Zhaoran Liu; Mengying Cui; David Levinson (TransportLab, School of Civil Engineering, University of Sydney) |
| Abstract: | Crash cost estimates are essential for evaluating road safety management policies and assessing the economic benefits of safety improvements. Existing studies often rely on aggregated crash data, assuming an even distribution of incidents, which overlooks significant spatial variations influenced by road characteristics and traffic conditions. This research presents a methodological framework for link-based crash cost analysis that considers both internal and external costs, enabling detailed quantification at a localized level. By employing safety performance functions and ordered probit models, we estimate on-road crash rates by crash type and injury severity, distinguishing between internal costs borne by individuals involved in crashes and external costs that impact victims, insurers, and government agencies. Applied to the Minneapolis-St. Paul metropolitan area, our findings reveal that costs incurred by drivers are higher than those imposed on others, and highways are generally safer than surface streets. However, these crash costs are too low relative to the value of travel time to significantly influence route choices, even if drivers are aware of them. Policies should consider incentives for safe driving practices; ongoing research and dynamic datasets are encouraged to capture changes in road safety conditions. |
| Keywords: | transportation, public transport, road transport, traffic safety, transport networks, travel behavior |
| JEL: | R40 |
| Date: | 2025 |
| URL: | https://d.repec.org/n?u=RePEc:nex:wpaper:transportist-2025-crashcosts-2 |
| By: | Abebe Dress Beza; Zhuopeng Xie; Mohsen Ramezani; David Levinson (TransportLab, School of Civil Engineering, University of Sydney) |
| Abstract: | The present study reviews a large body of scientific literature to explore the potential impacts of lane-less and lane-free traffic streams and examines the control strategies and trends of lane-free traffic through the lens of future transport. The findings indicate that lane-free traffic has the potential to positively impact road traffic, including an increase in traffic performance and a rise in road infrastructure capacity due to efficient space use and the seepage behavior of small-sized vehicles in mixed traffic scenarios. Furthermore, studies on lane-less traffic with human-driven vehicles provide essential insights into how AVs might be programmed to operate safely and effectively in complex settings. For instance, a lane-free traffic setting could be a better option for improving traffic flow when AVs vary in size and seepage behavior can be incorporated into driving characteristics. |
| Keywords: | transportation, road transport, automated vehicles |
| JEL: | R40 |
| Date: | 2025 |
| URL: | https://d.repec.org/n?u=RePEc:nex:wpaper:transportist-2025-lane-free-1 |
| By: | Zhe Dai; Mengying Cui; Kong Li; Lijie Yu; David Levinson (TransportLab, School of Civil Engineering, University of Sydney) |
| Abstract: | This paper builds a multi-modal, multi-scalar intercity accessibility framework integrating multiple layers of transport networks and coordinating actual route-choice preferences with theoretical optimal planning. Applied to the Guanzhong Plain Urban Agglomeration as proof-of-concept-particularly focusing on high-speed railway (HSR) impacts-the authors find that although spatial distributions of accessibility and HSR impact are similar to traditional door-to-door methods, the proposed multi-modal approach enables more precise network configurations. It effectively captures competition among alternative transport options and complementary roles of various modes connecting intercity hubs. Relying solely on traditional methods may bias investment evaluations, as our approach shows networking effects are amplified in before-and-after analyses that examine changes rather than static accessibility. |
| Keywords: | transportation, accessibility, public transport, high-speed rail, land use, transport networks |
| JEL: | R40 |
| Date: | 2025 |
| URL: | https://d.repec.org/n?u=RePEc:nex:wpaper:transportist-2025-hsraccess-4 |
| By: | Yang Gao; David Levinson (TransportLab, School of Civil Engineering, University of Sydney) |
| Abstract: | This paper collects data from the morning peak period (1995-2019) at 564 freeway detector stations in Minneapolis-St. Paul to assess changes in throughput over 25 years. We identify saturated stations at various saturation thresholds using fundamental diagrams, and evaluate throughput trends. Average network throughput fell from ~1850 vehicles/lane/hour in 1995 to ~1600 in 2019, while critical density dropped from ~24 to ~19 vehicles/km. Over this period, the number of trucks increased 153.7% overall (SUVs +1043.6%, tractor-trailers +128.9%). Granger causality tests across network and at permanent count stations support the hypothesis that an increasing truck share causes decreasing traffic throughput. In other words, fewer vehicles now cause congestion than before. The growing prevalence of large vehicles (trucks/SUVs) appears to reduce network capacity, suggesting that rising truck/SUV shares have contributed significantly to declining peak-period traffic throughput. |
| Keywords: | transportation, congestion, public transport, road transport, land use, transport networks |
| JEL: | R40 |
| Date: | 2025 |
| URL: | https://d.repec.org/n?u=RePEc:nex:wpaper:transportist-2025-trucks-5 |
| By: | Junjie Lin (Sun Yat-sen University); Cheng Keat Tang (Nanyang Technological University); Jos van Ommeren (Vrije Universiteit Amsterdam) |
| Abstract: | Electric vehicles (EVs) are typically 20% heavier than conventional internal combustion engine vehicles because of their dense battery packs and reinforced structures. While this additional mass shields EV occupants, it transfers disproportionately greater kinetic energy to other road users during collisions, exacerbating their injury severity. Here, we quantify this critical safety disparity using data from over 300, 000 two-vehicle collisions in California. We find that driving an EV reduces the occupant’s risk of serious injury or fatality by 18%. However, it significantly elevates the corresponding risk for occupants of colliding vehicles by 13%—an effect driven almost entirely by vehicle weight. Economically, these externalized accident costs offset approximately one-third of the environmental climate benefits of EVs, indicating that while EV adoption still yields a net gain in social welfare, it introduces profound safety inequities. As vehicle electrification accelerates globally to mitigate climate change, our findings highlight an urgent need for policies regulating fleet weight to ensure equitable road safety. |
| Keywords: | Police Killings, Underreporting, Medico-legal death investigation office |
| JEL: | D62 R41 |
| Date: | 2026–05–21 |
| URL: | https://d.repec.org/n?u=RePEc:tin:wpaper:20260025 |
| By: | Reka Juhasz; Dávid Krisztián Nagy; Claudia Steinwender; Woan Foong Wong |
| Abstract: | Maritime transport remains the backbone of global trade, yet the port and shipping network that carries it has been transformed by containerization and related technological advances. Drawing on newly available granular data — digitized historical shipping records, georeferenced ship movements, and shipment-level routing information — we present five stylized facts on the structure and evolution of the maritime network. Global shipping activity is highly concentrated among a changing lineup of dominant top ports even as lower-ranked ports disperse, while state-owned Chinese port terminal operators increasingly account for these global volumes, boosting overall port operations while delivering efficiency gains mostly to Chinese vessels. We use these facts to organize a synthesis of a fast-growing literature: containerization reshaped which port cities could expand, reinforced hub-and-spoke concentration that yields large but localized welfare gains, embedded ports in multimodal networks that amplify the returns to infrastructure, and generated market power, congestion, and environmental costs. Together, this evidence shows how evolving maritime technologies simultaneously deepen global integration and heighten the economic and geopolitical importance of critical nodes in the transport network — and of who controls them. |
| Keywords: | transport networks, ports, international trade, trade costs, containerization, geoeconomics |
| JEL: | F13 F14 R41 R42 |
| Date: | 2026 |
| URL: | https://d.repec.org/n?u=RePEc:ces:ceswps:_12793 |
| By: | Mengying Cui; Lijie Yu; Shaoyu Nie; Zhe Dai; Ying-en Ge; David Levinson (TransportLab, School of Civil Engineering, University of Sydney) |
| Abstract: | Spatial imbalances in metro ridership significantly reduce system efficiency. Understanding the contributing factors is essential for improving ridership equity and performance. This study introduces novel spatial dependency indices based on spatial weight matrices and land-use function complementarity to explore how access and inter-station spatial dependency affect metro ridership, focusing on station-level boardings/alightings and station-to-station flows. Using Xi'an Metro data, we find that access to employment and residences from metro stations greatly increases station boardings and alightings. Walking access emerges as critical, especially for station-to-station travel. The analysis also reveals a complementarity effect: increases in boardings at one station lead to higher demand at others, particularly where stations serve areas with complementary land uses. These findings underscore the key role of access and spatial dependency in enhancing transit planning and system efficiency. |
| Keywords: | transportation, accessibility, public transport, land use, active transport, transport equity |
| JEL: | R40 |
| Date: | 2025 |
| URL: | https://d.repec.org/n?u=RePEc:nex:wpaper:transportist-2025-metroflows-3 |
| By: | Ioannou, Petros; Wang, Zheyu |
| Abstract: | Current navigation applications estimate travel times based on current traffic conditions, without considering upcoming travel demand. A potential solution to this problem is a central coordination system that collects global travel demand information, enabling more accurate traffic projections. Monetary incentives or charges can be used to encourage drivers to follow assigned routes that contribute toward a system optimum, which represents the most efficient traffic state for the transportation network. The challenge in determining incentives lies in the heterogeneity of drivers, as each has different preferences. Traditionally, surveys have been used to estimate drivers’ routing preferences, but these suffer from respondent inconsistency and changing driver preferences. This research proposes a utility learning mechanism. Instead of relying on static survey data, the system periodically updates its understanding of drivers’ preferences by observing their route choices over time. This research brief discusses the results and effectiveness of the coordinated routing system and the utility learning mechanism. View the NCST Project Webpage |
| Keywords: | Engineering, Social and Behavioral Sciences, Congestion management systems, freight traffic, incentives, logits, route choice, routes and routing, truck drivers |
| Date: | 2026–07–01 |
| URL: | https://d.repec.org/n?u=RePEc:cdl:itsdav:qt37s3f9d4 |
| By: | Akbar, Prottoy; Couture, Victor |
| Abstract: | Urban transportation projects are massive public investments that can transform cities. This article reviews evidence on how these projects shape where people live, and how their benefits are shared across income groups. A simple model helps organize the findings. Three factors are especially important: who uses the new transportation mode, where it is built, and how easily people can relocate. Projects serving a narrow group in a specific area tend to increase segregation and inequality. These impacts can be severe if poorer households face barriers to relocation, as happened with the Interstate Highway System. Projects with broad spatial coverage and use by all income groups, like Bus Rapid Transit in developing countries, tend to have more modest segregation effects and broadly shared welfare gains. |
| Keywords: | Urban transportation; Segregation; Welfare |
| JEL: | R41 O18 |
| Date: | 2025–11 |
| URL: | https://d.repec.org/n?u=RePEc:cpr:ceprdp:20803 |
| By: | Corin Blanc |
| Abstract: | In response to rising urban air pollution, European cities have adopted Low Emission Zones (LEZs), restricting the most polluting vehicles. While effective in improving air quality, these policies remain controversial due to concerns over fairness and acceptability. This paper examines the impact of London’s 2021 and 2023 Ultra Low Emission Zone (ULEZ) expansions on Subjective Well-Being (SWB). Using panel data from the UK Household Longitudinal Study and a staggered difference-in-differences design with individual and year fixed effects, we compare changes in life satisfaction among residents inside and outside the affected areas. We find that the 2021 expansion led to a decline in life satisfaction by approximately 0.4 points. We explore the mechanisms driving this decline and find that the well-being loss is mediated by car dependency and transport mode availability. While the policy increased reliance on public transport, we show that a better accessibility to public transport mitigates the decline in life satisfaction among London residents. Furthermore, we show that the well-being costs of the policy are regressive, disproportionately affecting lower-income households. These findings suggest that LEZs can generate short-term and unequal well-being costs despite achieving modest behavioural change, highlighting the need for complementary measures to enhance social acceptability. |
| Keywords: | Low Emission Zones (LEZs), Air pollution, Environmental policy, Subjective well-being, Life satisfaction, Staggered Difference-in-differences, Social acceptability |
| JEL: | I31 Q52 H23 R48 |
| Date: | 2026 |
| URL: | https://d.repec.org/n?u=RePEc:drm:wpaper:2026-14 |
| By: | Robinson, Anya; Steren, Aviv PhD; Tal, Gil PhD |
| Abstract: | California has set a target of achieving 100% zero-emission vehicle (ZEV) sales by 2035. While the state has made substantial progress, with ZEVs accounting for roughly 25% of new vehicle sales in 2025, adoption remains uneven across communities. Disadvantaged communities (DACs), which face disproportionate exposure to air pollution, continue to lag in ZEV uptake. Most DAC-related policy efforts to date have focused on demand-side interventions, such as consumer purchase incentives, rather than supply-side approaches that increase vehicle availability. Because more than half of ZEV sales in California occur through franchised dealerships, they are a critical gateway through which consumers access these vehicles and may represent an important leverage point for increasing adoption. |
| Keywords: | Engineering |
| Date: | 2026–07–01 |
| URL: | https://d.repec.org/n?u=RePEc:cdl:itsdav:qt6pw1q9rf |
| By: | Han, Tianyu; Zhao, Bingyu PhD; Tang, Yili Kelly; Comfort, Louise PhD; Soga, Kenichi PhD |
| Abstract: | Earthquakes pose a persistent and significant threat to the movement of people, goods, and services. While agencies have made progress on emergency response, planning for recovery (how quickly transportation systems can be restored after a major event) remains limited. A key challenge is that earthquake modeling and transportation system modeling have remained largely separate efforts, making it difficult for agencies to anticipate disruptions, prioritize investments, and coordinate recovery across jurisdictions. |
| Keywords: | Engineering |
| Date: | 2026–07–01 |
| URL: | https://d.repec.org/n?u=RePEc:cdl:itsrrp:qt2210z53n |
| By: | Head, Keith; Mayer, Thierry; Melitz, Marc J; Yang, Chenying |
| Abstract: | We model a multi-stage supply chain for EVs from battery production to vehicle distribution. Given industrial policies, firms select where to open facilities at each stage. This is a difficult combinatorial choice problem that we solve with a fast mixed integer linear programming formulation. We estimate the variable and fixed costs parameters using SMM. Counterfactual simulations reveal a tension between boosting EV adoption and promoting domestic supply chains. Due to increasing returns, even unconditional subsidies raise the number of factories in the subsidizing region - by about 16% for EVs and 7% for cells in North America, and even more in Europe. Theoretically, local assembly requirements can push down delivered marginal costs relative to unconditional subsidies. Empirically, local content requirements quadruple the expansion of cell factories in America, but they drive up costs and reduce subsidy uptake, undoing more than half of the EV adoption stimulus coming from pure buyer subsidies. |
| Date: | 2026–02 |
| URL: | https://d.repec.org/n?u=RePEc:cpr:ceprdp:21184 |
| By: | Khatun, Farzana PhD; Pike, Susan PhD; Saphores, Jean-Daniel PhD |
| Abstract: | This study investigates free and reduced fare pass programs (FRFPs) for K-12, post-secondary, and college students across California since the COVID-19 pandemic and their role in ridership recovery. A survey of 67 transit agencies, including 34 with established FRFPs, indicates that most of them maintained their FRFPs between fiscal years 2018-2019 and 2022-2023, showcasing agencies' resilience despite financial uncertainty. LA Metro's GoPass enrolled over 241, 000 students and generated 1.2 million monthly boardings, inspiring similar initiatives. Post-pandemic, K-12 FRFPs saw significant expansion, improved funding, and a surge in ridership across participating agencies. These findings underscore the positive influence of fare-based incentives on student mobility and attendance. |
| Keywords: | Engineering, Transit passes, Free fares, Discount fares, Elementary school students, High school students, Ridership, Incentives, School trips, Travel surveys |
| Date: | 2026–07–01 |
| URL: | https://d.repec.org/n?u=RePEc:cdl:itsdav:qt4nt902kh |
| By: | Escamilla-Guerrero, David (University of St Andrews); Peri, Giovanni (University of California, Davis) |
| Abstract: | This paper leverages variation in the access to the Mexican railroad network in the early 1900s to estimate its impact on migration to the United States and evaluate its long-run persistence after passenger rail service became obsolete. Using an IV strategy based on least-cost paths between historical cities, we find that locations with railroad access had migration rates four times higher than those without in the early twentieth century. Sequential migration was the key mechanism: railroads first facilitated internal mobility toward railroad hubs, then onward migration to the US. Railroad access also contributed to structural transformation, raising urbanization and local economic development. In terms of persistence, locations with historical railroad access show weakly lower total migration rates to the US in the early 21st century, consistent with local economic growth reducing the incentive to migrate. Yet destination-specific patterns prove remarkably durable: locations that disproportionately sent migrants to California, Arizona, or Texas in the 1900s continued to do so in the 2000s, reflecting the persistence of migrant networks. |
| Keywords: | railroads, Mexico-US migration, migration networks, economic growth |
| JEL: | J61 N36 N76 O31 R42 |
| Date: | 2026–06 |
| URL: | https://d.repec.org/n?u=RePEc:iza:izadps:dp18736 |
| By: | Shawn Berry |
| Abstract: | Deciding where to live involves a complex balance between commuting and moving, as households must weigh housing affordability, transportation expenses, access to workplaces, and social ties. Traditional urban economic theories focus on the balance between housing expenses and commuting costs, while modern studies also consider housing affordability, transportation access, and utility maximization. However, few studies have combined these elements into a clear mathematical model that can be used for both policy analysis and household decision-making. This paper introduces an algebraic model for deciding whether to commute or move, expanding on traditional residential location theories by including direct housing and commuting expenses, income-related affordability limits, indirect social and service access costs, and location-based utility within a single utility-maximization framework. The model uses the common 30% housing affordability rule as a constraint, acknowledging that residential choices are also shaped by social networks, access to institutions, neighborhood ties, and quality-of-life factors. The decision rule derived from the model integrates direct financial costs with weighted social benefits and indirect access costs to assess when moving offers more overall utility than staying put and commuting. Unlike complex discrete-choice, nested-logit, or agent-based models, this framework offers a mathematically clear, understandable, and flexible decision model that can easily be expanded to include more household characteristics, transportation options, or policy factors. The model advances urban economics, migration studies, and housing affordability research by providing a practical analytical tool for assessing residential mobility decisions within financial and behavioral limits. |
| Date: | 2026–06 |
| URL: | https://d.repec.org/n?u=RePEc:arx:papers:2606.31780 |
| By: | Hwang, Roland; Dhole, Anuj; Fulton, Lewis; Murphy, Colin |
| Abstract: | The California medium- and heavy-duty zero emission vehicle (ZEV) market is poised for growth despite challenges to regulatory authority at the federal level. To ensure market momentum, long-term funding certainty is needed for the medium- and heavy-duty ZEV incentive program, called HVIP. In 2024, the CARB board voted to redirect the Clean Fuel Reward (CFR) program from light-duty ZEVs to medium- and heavy-duty zero-emission truck (ZET) incentives. While this provides a foundation for revenue for ZET incentives, ITS-Davis analysis finds that it will likely fall far short of long-term HVIP revenue needs. We estimate the total HVIP funding gap (including both ZETs and ZEBs) after CFR revenues are considered for the 9-year period from 2027-2035 to be between $4.2 billion and $26 billion, with a mid-case scenario funding gap of $8.5 billion. The wide range is due to uncertainties in ZEV market growth rates and CFR revenues. The funding gap necessitates new approaches to address, such as lowering the incentive levels per vehicle, implementing new funding sources, and adopting innovative financing mechanisms. For example, we estimate that reducing the average incentive by 50% starting in 2031 and assessing a $1, 400 registration fee on Class 4-8 diesel trucks starting in 2027 could support the achievement of annul ACT target volumes in the post-2030 timeframe. |
| Keywords: | Social and Behavioral Sciences |
| Date: | 2026–07–01 |
| URL: | https://d.repec.org/n?u=RePEc:cdl:itsdav:qt16x180rr |
| By: | Christian Bogmans (International Monetary Fund); Gerard van der Meijden (Vrije Universiteit Amsterdam); Cees Withagen (Vrije Universiteit Amsterdam) |
| Abstract: | We analyze a dynamic spatial model of deforestation in which roads facilitate agricultural expansion. The model's key innovation is that road construction costs decrease with the existing road stock, creating positive network externalities that are specific to infrastructure: each road built serves as a stepping stone for further road construction. Under open access, myopic producers fail to internalize that roads built today facilitate future road construction. As a result, the pace of deforestation is faster under a forward-looking regime of private property than open access, reversing a standard result from resource economics. We calibrate the model to the Brazilian Amazon, where cattle ranching is the primary driver of deforestation, and calculate the international transfer required to incentivize Brazil to implement a carbon tax that completely stops deforestation. We find that Brazil's extensive existing road network increases this required transfer, demonstrating how infrastructure creates ``deforestation lock-in'' that makes conservation progressively more expensive. |
| JEL: | Q15 Q23 Q24 Q54 R12 R13 |
| Date: | 2026–06–11 |
| URL: | https://d.repec.org/n?u=RePEc:tin:wpaper:20260032 |
| By: | Hannes Wallimann; C\'edric Br\"utsch; Martin Huber |
| Abstract: | Fare evasion generates substantial revenue losses for public transport operators and is typically combated through fare inspections, yet little is known about how the mode of inspection-uniformed versus plainclothes-affects detection efficiency. Using a unique dataset of 21, 727 inspection records from PostAuto, the largest regional bus operator in Switzerland, we apply causal machine learning to estimate the causal effect of inspector visibility on inspection efficiency, defined as detected fare evaders per inspection hour. Our results indicate that plainclothes inspections are, on average, significantly more effective than uniformed inspections, with an estimated average treatment effect of -0.173 incidents per hour, corresponding to a relative reduction of approximately 26%. Heterogeneity analyses find no evidence of systematic effect variation across contextual characteristics, suggesting that the superiority of plainclothes inspections is robust and pervasive across the PostAuto network. When applying optimal policy learning (based on policy trees) to optimally target subgroups by one or the other treatment depending on relative effectiveness, plainclothes inspections are recommended for the large majority of contexts (83.3%), with uniformed inspections suggested only for lines characterised by a below-median share of foreign residents and above-median population size. |
| Date: | 2026–06 |
| URL: | https://d.repec.org/n?u=RePEc:arx:papers:2606.24181 |
| By: | Luiu, Carlo; Wandera, Amos; Bukachi, Vera; Day, Rosie |
| Abstract: | Despite significant discussions on transport inequalities in African cities, older people's mobility needs remain under-researched. To gain a deeper understanding of such issues, this study focuses on older people living in Kenyan informal settlements and uses the capability approach to investigate their options for mobility, activities and locations, barriers, coping strategies and unfulfilled mobility needs. The study employs a qualitative approach comprising four focus groups with 24 participants and a follow-on community engagement workshop with people aged above 50 years old living in the informal settlement of Kibera in Nairobi. The results indicate that older people face significant challenges in their everyday mobility. Living with poor health conditions, level of poverty, lack and poor quality of walking infrastructure, personal safety and ageist behaviour are the main factors shaping and affecting their mobility. The capability approach offers a framework to understand older people’s mobility practices and implications for wellbeing. It enables an analysis of how mobility is shaped by their needs, constraints and decision-making processes, and how this translates into participation in life. It also offers an exploration of how mobility enables and supports a wider capability set, outlining its multidimensional social impacts. |
| Date: | 2026–06–15 |
| URL: | https://d.repec.org/n?u=RePEc:osf:socarx:fkh7z_v1 |