Transportation Research Part A-Policy and Practice最新文献_第5页

Management measures to improve safety of partially automated vehicles on rural roads using artificial neural networks 利用人工神经网络提高部分自动化车辆在农村道路上的安全性的管理措施

IF 6.8 1区工程技术 Q1 ECONOMICS

Transportation Research Part A-Policy and Practice

Pub Date : 2026-01-22 DOI: 10.1016/j.tra.2026.104882

Griselda López , Víctor Ramos , Sara Moll , Jorge Molines

Concerns regarding the safety of partial automated vehicles (AVs) remain prevalent, especially in complex roadway environments. AVs incorporate Advanced Driving Assistance Systems to perform the dynamic driving task; however, unexpected disengagements of the systems still occur due to various contextual and infrastructural factors. Among these, two-lane rural roads—with their geometric design and operational challenges—represent a critical setting. Notably, a high number of disengagements are concentrated on horizontal curves.

This study analyzes naturalistic disengagement data from two SAE Level 2 AVs operating on different segments of two-lane rural roads. The horizontal curves were characterized across geometrical and operational variables (radii, curvature change rate (CCR), curve direction, speed or visibility). These variables served as inputs to an artificial neural network (ANN) model designed to predict disengagement occurrences.

The ANN, a feedforward multilayer perceptron with one hidden layer, was trained using backpropagation. Performance was validated with K-fold cross-validation, and accuracy assessed via cross-entropy loss and confusion matrices. A Monte Carlo-style simulation tested robustness by generating multiple confusion matrices from randomized data partitions to evaluate classification stability. The results highlight CCR and lane width as key predictive factors. The calibrated ANN demonstrated robust classification (accuracy = 87.8 %, sensitivity = 92.7 %, specificity = 85.9 %) in identifying curve segments with a higher likelihood of disengagement.

This study provides road administrations a new neural network derived empirical formula to identify potential AV disengagement zones. By identifying risk-prone areas, authorities can consider targeted measures—such as enhanced signage or driver alerts— to support safer and more efficient automated driving in rural settings.

对部分自动驾驶汽车（AVs）安全性的担忧仍然普遍存在，尤其是在复杂的道路环境中。自动驾驶汽车采用高级驾驶辅助系统来执行动态驾驶任务；然而，由于各种上下文和基础设施因素，系统的意外脱离仍然会发生。其中，具有几何设计和运营挑战的双车道农村公路代表了一个关键的环境。值得注意的是，大量的脱离集中在水平曲线上。该研究分析了两辆SAE 2级自动驾驶汽车在两车道农村道路不同路段上的自然脱离数据。通过几何和操作变量（半径、曲率变化率（CCR）、曲线方向、速度或能见度）对水平曲线进行表征。这些变量作为人工神经网络（ANN）模型的输入，用于预测脱离事件的发生。人工神经网络是一个具有一个隐藏层的前馈多层感知器，使用反向传播方法进行训练。通过K-fold交叉验证验证性能，并通过交叉熵损失和混淆矩阵评估准确性。蒙特卡罗式模拟通过从随机数据分区生成多个混淆矩阵来评估分类稳定性，从而测试鲁棒性。结果表明，CCR和车道宽度是关键的预测因素。校正后的人工神经网络在识别高脱离可能性的曲线段方面表现出鲁棒性分类（准确率= 87.8%，灵敏度= 92.7%，特异性= 85.9%）。该研究为道路管理部门提供了一种新的神经网络经验公式来识别潜在的自动驾驶脱离区。通过识别风险易发区域，当局可以考虑采取有针对性的措施，例如增强标识或驾驶员警报，以支持在农村环境中更安全、更有效的自动驾驶。

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引用次数: 0

Market reactions to new aircraft deployment in China’s domestic Aviation: A panel vector autoregression analysis of C919 中国国内航空市场对新飞机部署的反应：基于C919的面板向量自回归分析

IF 6.8 1区工程技术 Q1 ECONOMICS

Transportation Research Part A-Policy and Practice

Pub Date : 2026-01-22 DOI: 10.1016/j.tra.2026.104883

Yonglei Jiang , Chunan Wang , Lei Wang , Shuli Liu , Anming Zhang

This paper examines market responses to the commercial deployment of China’s domestically developed C919 jetliner across nine major domestic routes, using high-frequency flight-level data and public attention indices. By estimating a system-GMM panel vector autoregression (PVAR), we test whether a new aircraft type shifts demand and pricing. Results indicate a two-stage dynamic: attention spikes often precede selective entry; after entry, fare cuts and load factor gains are modest and short-lived, with behavior reverting as operations stabilize and scheduling/demand dominate. Carrier heterogeneity is present but does not overturn the qualitative pattern. This study provides empirical insights into the diffusion of emerging aircraft models and offers guidance for aviation management and industrial policy within the context of China’s evolving air transport system.

本文利用高频飞行级数据和公众关注指数，考察了中国国产C919客机在九条主要国内航线上的商业部署的市场反应。通过估计系统- gmm面板向量自回归（PVAR），我们检验了新机型是否会改变需求和定价。研究结果显示了两阶段的动态：注意力峰值通常发生在选择性进入之前；进入市场后，票价的降低和客座率的提高是适度和短暂的，随着运营的稳定和调度/需求的主导，行为会恢复。载体异质性是存在的，但并不推翻定性模式。本研究为新兴飞机模型的传播提供了实证见解，并为中国航空运输系统不断发展的背景下的航空管理和产业政策提供了指导。

引用次数: 0

Roadspace allocation between autos, buses, and bicycles with heterogeneous demand 具有异构需求的汽车、公共汽车和自行车之间的道路空间分配

IF 6.8 1区工程技术 Q1 ECONOMICS

Transportation Research Part A-Policy and Practice

Pub Date : 2026-01-22 DOI: 10.1016/j.tra.2026.104884

Yang Gao , Andres Fielbaum , David Levinson

The allocation of road space among different transport modes has long been a key issue in urban planning, yet it lacks solid theoretical foundations. This paper investigates the optimal allocation of road space among three transport modes: private vehicles, buses, and bicycles, for overall system performance. The travel time for each mode is determined based on travel speed derived from fundamental diagrams (FDs). Changes in bus travel time are the least sensitive to excessive demand, as the number of buses is only indirectly affected by demand. A mode choice equilibrium framework based on deterministic user equilibrium is proposed to handle cases with and without heterogeneity in passengers’ waiting time thresholds for buses. Analytical and numerical results reveal that the optimal road space allocation strategy depends on the demand level. Without considering passenger heterogeneity, the optimal strategy is a corner solution - allocating all road space to one of the three transport modes. When heterogeneity is considered, low and medium demand levels result in all space being allocated to private vehicles and bicycles, respectively. For high demand levels, the optimal solution is a non-corner solution, where road space is allocated to both buses and bicycles, and the proportion allocated to buses increases as demand rises. The initial road space share for buses significantly influences system performance. Crucially, this induces either a virtuous or vicious cycle that impacts public transport usage. The threshold for this effect is around 0.4, meaning that allocating approximately half of the road space to buses is critical, and this threshold decreases as demand increases. This study highlights the importance of tailoring road space allocation strategies to demand levels to maximize transport efficiency.

道路空间在不同交通方式之间的分配一直是城市规划中的关键问题，但缺乏坚实的理论基础。本文研究了私家车、公共汽车和自行车三种交通方式下道路空间的最优分配，以实现系统的整体性能。每一种模式的运行时间是根据由基本图（FDs）得出的运行速度来确定的。公交车行驶时间的变化对过度需求最不敏感，因为公交车数量只间接受到需求的影响。针对公交乘客等待时间阈值存在异质性和不存在异质性的情况，提出了一种基于确定性用户均衡的模式选择均衡框架。分析和数值结果表明，最优道路空间分配策略取决于需求水平。在不考虑乘客异质性的情况下，最优策略是将所有道路空间分配给三种运输方式中的一种。当考虑异质性时，低需求和中等需求水平导致所有空间分别分配给私家车和自行车。对于高需求水平，最优解决方案是无拐角解决方案，其中道路空间分配给公共汽车和自行车，并且分配给公共汽车的比例随着需求的增加而增加。公共汽车的初始道路空间份额对系统性能有显著影响。至关重要的是，这会导致影响公共交通使用的良性或恶性循环。这种影响的阈值大约是0.4，这意味着将大约一半的道路空间分配给公共汽车是至关重要的，这个阈值随着需求的增加而降低。这项研究强调了根据需求水平调整道路空间分配策略以最大化运输效率的重要性。

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引用次数: 0

How to improve the AV safety: From the understanding of AV crashes to safety enhancement strategy 如何提高自动驾驶汽车的安全性：从对自动驾驶汽车碰撞的认识到安全增强策略

IF 6.8 1区工程技术 Q1 ECONOMICS

Transportation Research Part A-Policy and Practice

Pub Date : 2026-01-22 DOI: 10.1016/j.tra.2026.104880

Yao Wu , Yuanwei Luo , Yupeng Liu , Yi Lin , Yanyong Guo

Autonomous vehicles (AVs) are increasingly prioritized in national transport strategies for their potential to improve safety and sustainability. Yet real-world crashes show that AVs remain vulnerable to safety risks, highlighting the need to understand their crash patterns and develop evidence-based countermeasures. The objective of this study is to investigate the factors associated with AV crashes and develop safety countermeasure to improve AV safety. 335 AV crash data from 2021 to 2022 was collected from collision reports from San Francisco at Traffic Analysis Zones (TAZ) level. Sociodemographic, built environment, land-use, and exposure variables were incorporated into Ordinary Least Squares (OLS) and Geographically Weighted Regression (GWR) models. Compared with OLS, the GWR model provides a superior fit, as reflected by its lower AIC (535.17) and residual sum of squares (580.66). Model results revealed diverse effects of build environment on AV crashes across TAZs. Specifically, bus stop and transit lane densities exhibit strong negative associations with crash frequency, particularly in the southwestern regions. Bicycle parking density is negatively correlated with crashes. In contrast, wider sidewalks and higher proportions of speed limit zones are positively associated with AV crashes in certain urban areas. The impact of traffic signal density is spatially inconsistent—showing a crash-reducing effect in northeastern urban areas but a positive association in southwestern regions. Safety countermeasures were proposed from the perspective of understanding the AV crash influencing factors. The study underscores the significance of well-planned transportation facilities in enhancing AV safety.

自动驾驶汽车（av）因其提高安全性和可持续性的潜力，在国家交通战略中越来越受到重视。然而，现实事故表明，自动驾驶汽车仍然容易受到安全风险的影响，这凸显了了解其碰撞模式并制定基于证据的对策的必要性。本研究旨在探讨自动驾驶汽车碰撞的相关因素，并提出相应的安全对策，以提高自动驾驶汽车的安全性。从旧金山的交通分析区（TAZ）级别的碰撞报告中收集了2021年至2022年的335个自动驾驶汽车碰撞数据。社会人口统计学、建筑环境、土地利用和暴露变量被纳入普通最小二乘（OLS）和地理加权回归（GWR）模型。与OLS模型相比，GWR模型具有较好的拟合性，其AIC（535.17）和残差平方和（580.66）均较低。模型结果揭示了建筑环境对自动驾驶汽车在taz内碰撞的不同影响。具体而言，公交车站和公交车道密度与撞车频率呈强烈负相关，尤其是在西南地区。自行车停放密度与交通事故呈负相关。相比之下，在某些城市地区，更宽的人行道和更高比例的限速区与自动驾驶汽车碰撞呈正相关。交通信号密度的影响在空间上是不一致的，在东北城市地区表现为减少交通事故的作用，而在西南地区表现为正相关。从了解自动驾驶汽车碰撞影响因素的角度出发，提出了安全对策。该研究强调了规划良好的交通设施对提高自动驾驶安全的重要性。

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引用次数: 0

Understanding crowd-shipping acceptance: A hierarchical latent class personality-attitude hybrid choice model 理解大众运输的接受程度：一个等级潜在阶级人格-态度混合选择模型

IF 6.8 1区工程技术 Q1 ECONOMICS

Transportation Research Part A-Policy and Practice

Pub Date : 2026-01-20 DOI: 10.1016/j.tra.2026.104878

Dianqing Zhou, Soora Rasouli, Melvin Wong

This study aims to explore how people’s reported trip characteristics, personality traits and attitudes are associated with their willingness to participate in crowd-shipping (CS) system. CS is an emerging concept aiming at reducing the footprint of dedicated delivery trips. Within this service, ordinary citizens can be matched with a parcel with the origin and destination of close proximity to the traveler’s start and end of the pre-planned trip. To measure the feasibility and potential of CS, a stated adaptation choice (SAC) experiment was conducted, offering two unlabeled options adapted to the reported trips of respondents, plus the possibility of rejecting the request. A hierarchical latent class personality-attitude hybrid choice model (HLCPA-HCM) is employed to capture the variation in preference across individuals, providing insights into the discrete heterogeneity of different types of travelers. The model is estimated using the data collected from an SAC experiment, distributed among 486 respondents in the Netherlands. The results confirm the hierarchical structure of personality traits and attitudes, so that personality traits affect attitudes and attitudes contribute to the class-membership probability. Trip characteristics such as the number of trip legs and the mode used in the pick-up leg, CS attributes such as detours and monetary incentives, as well as the share of social network being active in the CS system significantly influence the CS acceptance. These findings offer valuable guidance for CS operators in customizing the parcel allocation and help to foster the growth of CS services.

本研究旨在探讨人们所报告的旅行特征、个性特征和态度与他们参与群体运输（CS）系统的意愿之间的关系。“速递”是一个新兴概念，旨在减少专用送货行程的足迹。在这项服务中，普通公民可以匹配到一个包裹，该包裹的起源地和目的地与旅行者预先计划的旅行起点和终点非常接近。为了衡量CS的可行性和潜力，进行了一个陈述适应选择（SAC）实验，提供了两个适应于受访者报告的旅行的未标记选项，以及拒绝请求的可能性。采用层次潜类人格-态度混合选择模型（HLCPA-HCM）捕捉个体间的偏好差异，揭示不同类型旅行者的离散异质性。该模型是使用从SAC实验中收集的数据进行估计的，该实验分布在荷兰的486名受访者中。研究结果证实了人格特质和态度的层次结构，即人格特质影响态度，态度影响班级成员概率。出行特征（如行程数和接送方式）、CS属性（如绕路和金钱激励）以及CS系统中活跃的社交网络份额显著影响CS接受度。这些研究结果为物流运营商定制包裹分配提供了有价值的指导，有助于促进物流服务的发展。

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引用次数: 0

Do fringe benefit cars make the car fleet greener? 附加福利汽车会使车队更环保吗？

IF 6.8 1区工程技术 Q1 ECONOMICS

Transportation Research Part A-Policy and Practice

Pub Date : 2026-01-19 DOI: 10.1016/j.tra.2026.104881

Carl Berry , Maria Börjesson

It has proven difficult to reduce carbon emissions from the transport sector; in fact, emissions from this sector are still increasing worldwide. Reducing emissions by reducing road transport is challenging; therefore, a transition to a vehicle fleet with low or zero emissions seems essential. Many new cars in OECD countries are sold to firms as fringe benefit cars (sometimes called company cars in the literature). The generous taxation of such cars has been shown to have negative welfare effects because it increases the consumption of cars. However, it is sometimes justified since it speeds up the transition of the car fleet to lower-emission vehicles. The purpose of this paper is to analyze how fringe benefit cars impact carbon emissions, fuel type, weight, size, engine power, and market value of new cars. We apply micro register data including all adult Swedes and their cars, spanning the years 1999 to 2020. By using a matching model that combines Exact matching and Mahalanobis distance matching, the fuel consumption of the fringe benefit car is compared to the hypothetical new private car that the employee receiving the fringe benefit would have otherwise purchased. We find that new fringe benefit cars tend to be larger, heavier, and more powerful than the hypothetical new private cars that fringe benefit car recipients would have otherwise purchased, However, we also find that new fringe benefit cars sold in 2019–2020 consumed 1.2 L less fuel per 100 km compared to hypothetical new private cars, a decrease of 20 percent. The lower fuel consumption of the fringe benefit cars in these years results from a higher share of electric vehicles among them. We also find that the likelihood of the fringe benefit car being an alternative-fuelled vehicle is 6 percentage points higher than if it was bought as a private car.

事实证明，减少运输部门的碳排放是困难的；事实上，该行业的排放量在全球范围内仍在增加。通过减少道路运输来减少排放具有挑战性；因此，向低排放或零排放的车队过渡似乎是必不可少的。经济合作与发展组织国家的许多新车作为附加福利车出售给公司（在文献中有时被称为公司车）。对此类汽车的慷慨征税已被证明具有负面的福利效应，因为它增加了汽车的消费。然而，它有时是合理的，因为它加速了汽车向低排放车辆的过渡。本文的目的是分析附加福利汽车如何影响新车的碳排放，燃料类型，重量，尺寸，发动机功率和市场价值。我们采用微型登记数据，包括1999年至2020年期间所有瑞典成年人和他们的汽车。通过使用精确匹配和马哈拉诺比斯距离匹配相结合的匹配模型，将附加福利汽车的燃油消耗与接受附加福利的员工原本会购买的假想新私家车进行比较。我们发现，新的附加福利汽车往往比附加福利汽车接受者原本购买的假设的新私家车更大、更重、更强劲。然而，我们还发现，2019-2020年销售的新附加福利汽车每百公里油耗比假设的新私家车少1.2升，减少了20%。近年来，附加效益车的油耗之所以较低，是因为其中电动汽车的比例较高。我们还发现，附带福利车是替代燃料汽车的可能性比作为私家车购买的可能性高6个百分点。

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引用次数: 0

Freight-on-transit: A systematic review centered on freight needs, methods, and real-world implementations 运输货运：以货运需求、方法和实际实现为中心的系统回顾

IF 6.8 1区工程技术 Q1 ECONOMICS

Transportation Research Part A-Policy and Practice

Pub Date : 2026-01-16 DOI: 10.1016/j.tra.2026.104864

Manuela Córdoba-Misas , Oriana Calderón , Candace Brakewood

Transportation systems face spatial constraints that limit infrastructure expansion and complicate freight movement in dense city centers. Freight on Transit (FOT)—the shared use of public transit vehicles and infrastructure for goods transportation—has emerged as a strategy to improve last-mile logistics, reduce congestion, and support environmental goals. This research conducts a systematic review to consolidate current research on the methodological frameworks, operational strategies, and institutional dimensions of FOT. A total of 51 peer-reviewed studies were analyzed, covering both qualitative and quantitative approaches, with topics ranging from optimization models and simulation techniques to stakeholder analysis and policy frameworks. While the review examines FOT research broadly, it also expands the discussion on freight-specific considerations, such as commodity type, geographic context, and time-of-day factors, which are essential for assessing the feasibility, scalability, and policy relevance of integrated transit-freight operations. These aspects, although not consistently addressed across all studies, represent critical parameters influencing service design, operational performance, and practical implementation. Key findings highlight that technical feasibility is well-supported by modeling studies, but political, institutional, and regulatory barriers remain significant challenges to real-world implementation. Research efforts are heavily concentrated in urban environments, with limited empirical validation and few rural applications. This review contributes to the literature by providing a structured synthesis of FOT research and emphasizing the freight requirements that shape operational design, policy frameworks, and decision-making. The findings offer guidance for researchers, practitioners, and policymakers working to advance integrated, multimodal urban logistics solutions.

交通运输系统面临空间限制，这限制了基础设施的扩张，并使人口密集的城市中心的货运复杂化。过境货运（FOT）——共享使用公共交通车辆和基础设施进行货物运输——已经成为改善最后一英里物流、减少拥堵和支持环境目标的一项战略。本研究对现有的研究进行了系统的回顾，以巩固对FOT的方法框架、操作策略和制度维度的研究。共分析了51项同行评议研究，涵盖定性和定量方法，主题从优化模型和模拟技术到利益相关者分析和政策框架。虽然本报告广泛地考察了运输成本研究，但它也扩展了对货运特定因素的讨论，如商品类型、地理环境和时间因素，这些因素对于评估综合过境货运业务的可行性、可扩展性和政策相关性至关重要。这些方面虽然没有在所有研究中得到一致的解决，但却是影响服务设计、操作性能和实际实现的关键参数。主要研究结果强调，技术可行性得到了建模研究的良好支持，但政治、制度和监管障碍仍然是现实世界实施的重大挑战。研究工作主要集中在城市环境，经验验证有限，农村应用很少。本综述通过提供FOT研究的结构化综合并强调影响运营设计、政策框架和决策的货运需求，对文献做出了贡献。研究结果为致力于推进综合、多式联运城市物流解决方案的研究人员、从业人员和政策制定者提供了指导。

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引用次数: 0

Is the opening of high-speed rail conducive to aviation carbon reduction? Evidence from Beijing-Shanghai market in China 高铁开通有利于航空减碳吗？证据来自中国的京沪市场

IF 6.8 1区工程技术 Q1 ECONOMICS

Transportation Research Part A-Policy and Practice

Pub Date : 2026-01-15 DOI: 10.1016/j.tra.2026.104865

Qing Ji , Shuai Yue , Chunan Wang , Ying Fan

We take the Beijing-Shanghai high-speed rail (HSR) as a case and utilize a random-coefficient discrete choice model (BLP model) integrated with counterfactual simulations to systematically evaluate the impact of HSR opening on aviation market structure and carbon emissions of the transportation system. The results show that after the entry of the Beijing-Shanghai HSR, the absolute values of own-price elasticity and cross-price elasticity of airline passengers decrease by 15.65% and 17.98%, respectively, leading to a 22.12% reduction in air passenger traffic volume. If only the aviation sector is considered, the substitution effect of HSR can reduce carbon emissions by 123,400 tons in 2012, equivalent to imposing a carbon tax of $2.78 per airline ticket. However, with induced travel, the system-wide net effect depends on what additional HSR passengers would have done without HSR. If they would not have traveled or would have used conventional rail, total emissions rise by 915,900–1,398,400 tons in 2012 in some scenarios. If they are mainly diverted from private cars, the net effect is much smaller and can become negative. Further simulations indicate that a reduction of HSR’s unit carbon emission intensity by 40% to below 0.014272 kg/pkm would achieve a net reduction in overall carbon emissions. The study reveals that the emission reduction effectiveness of HSR strongly depends on the cleanliness of the power grid and the utilization rate of HSR capacity. This paper provides empirical evidence for carbon neutrality strategies in the transportation sector and emphasizes the need for policy trade-offs between environmental benefits from modal substitution and externalities from induced travel.

本文以京沪高铁为例，采用随机系数离散选择模型（BLP）和反事实模拟相结合的方法，系统评价了高铁开放对航空市场结构和交通运输系统碳排放的影响。结果表明，京沪高铁开通后，航空旅客自身价格弹性绝对值和交叉价格弹性绝对值分别下降15.65%和17.98%，导致航空客运量减少22.12%。如果只考虑航空业，2012年高铁的替代效应可以减少12.34万吨碳排放，相当于每张机票征收2.78美元的碳税。然而，对于诱导旅行，整个系统的净效应取决于没有高铁的额外高铁乘客会做些什么。在某些情况下，如果他们不出行或使用传统铁路，2012年的总排放量将增加915,900-1,398,400吨。如果它们主要是从私家车转移过来的，净影响要小得多，而且可能是负面的。进一步的模拟表明，将高铁的单位碳排放强度降低40%至0.014272 kg/pkm以下，将实现总体碳排放的净减少。研究表明，高铁的减排效果在很大程度上取决于电网清洁度和高铁容量利用率。本文为交通运输部门的碳中和战略提供了经验证据，并强调需要在模式替代带来的环境效益和诱导出行带来的外部性之间进行政策权衡。

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引用次数: 0

Unconscious status and car consumption: social comparison effects in a discrete choice experiment 无意识地位与汽车消费：离散选择实验中的社会比较效应

IF 6.8 1区工程技术 Q1 ECONOMICS

Transportation Research Part A-Policy and Practice

Pub Date : 2026-01-14 DOI: 10.1016/j.tra.2026.104873

Julia Bronnmann , Till Requate , Philipp Steinbrunner

This study investigates how social comparison affects consumers’ willingness to pay (WTP) for status-related car attributes. Drawing on theories of positional goods and social utility, we designed a discrete choice experiment (DCE) with a contextual priming component to measure the influence of perceived peer car status on WTP. A representative online sample of 1,289 German car owners evaluated car alternatives that varied in terms of engine power, car segment, SUV type, brand, interior equipment, and purchase price. We estimate both Mixed Logit and Latent Class models in WTP space to capture preference heterogeneity and social context effects. The results show that marginal WTP increases significantly with the perceived status of cars owned by peers, despite the fact that most respondents self-reported little to no influence. Our findings provide novel behavioral evidence of unconscious status consumption and offer a rationale for designing a status-based car tax to address positional externalities in transportation markets.

本研究探讨社会比较如何影响消费者对与地位相关的汽车属性的支付意愿。根据位置商品理论和社会效用理论，我们设计了一个带有情境启动成分的离散选择实验（DCE）来衡量感知同伴汽车状态对WTP的影响。对1289名德国车主进行了有代表性的在线抽样调查，评估了发动机功率、车型、SUV类型、品牌、内饰设备和购买价格等方面的不同选择。我们估计了WTP空间中的混合Logit和潜在类别模型，以捕获偏好异质性和社会背景效应。结果表明，边际WTP随着同行所拥有汽车的感知地位而显著增加，尽管大多数受访者自我报告的影响很小或没有影响。我们的研究结果为无意识身份消费提供了新的行为证据，并为设计基于身份的汽车税以解决交通运输市场的位置外部性提供了理论依据。

引用次数: 0

A sustainable maritime supply chain framework: an overview for academics and practitioners 可持续的海上供应链框架：学术界和实践者概述

IF 6.8 1区工程技术 Q1 ECONOMICS

Transportation Research Part A-Policy and Practice

Pub Date : 2026-01-14 DOI: 10.1016/j.tra.2026.104863

Ahmad Jafarian , Parisa Dolati Neghabadi , Nasrin Asgari , Reza Zanjirani Farahani

Maritime transportation accounts for over 80% of global trade by volume, primarily due to its cost efficiency. As global supply chains evolve, sustainability has become a critical concern for the maritime sector. This study reviews the most relevant papers on maritime transportation, sustainable supply chains, and maritime supply chains (MSC), aiming to advance the field through the development of an integrated classification framework. The proposed framework systematically categorizes existing academic studies based on supply chain planning features, key maritime stakeholders, and sustainability dimensions. We begin by analyzing the MSC network, focusing on its structural components and interconnections, including ports, shipping companies, and maritime logistics providers. We then examine MSC planning problems, emphasizing decision-making and optimization challenges across three core dimensions: time horizon, product/service type, and geography. Subsequently, we explore the interactions among stakeholders, highlighting how their collaborative and competitive dynamics influence sustainability outcomes. The proposed framework enables a structured evaluation of maritime logistics sustainability, bridging the gap between regulatory requirements and practical industry applications. By addressing two key aspects: (1) a micro-level analysis of sustainability challenges, stakeholder interactions, and solution approaches, and (2) a critical discussion of key trends, research gaps, and future directions, this paper offers a practical roadmap for integrating sustainability into the maritime transportation sector. The insights provided are valuable for both academic research and industry practice.

海运占全球贸易量的80%以上，主要是由于其成本效益。随着全球供应链的发展，可持续性已成为海事部门的一个关键问题。本研究回顾了关于海上运输、可持续供应链和海上供应链（MSC）的最相关论文，旨在通过开发一个综合分类框架来推进该领域的发展。提出的框架基于供应链规划特征、关键海事利益相关者和可持续性维度对现有学术研究进行了系统分类。我们首先分析MSC网络，重点关注其结构组成和相互联系，包括港口、航运公司和海上物流提供商。然后，我们研究MSC规划问题，强调决策和优化挑战跨越三个核心维度：时间范围、产品/服务类型和地理。随后，我们探讨了利益相关者之间的相互作用，强调了他们的合作和竞争动态如何影响可持续性结果。拟议的框架能够对海上物流可持续性进行结构化评估，弥合监管要求和实际行业应用之间的差距。通过解决两个关键方面：(1)可持续性挑战、利益相关者互动和解决方案的微观分析；(2)关键趋势、研究差距和未来方向的关键讨论，本文为将可持续性融入海运部门提供了一个实用的路线图。所提供的见解对学术研究和行业实践都很有价值。

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引用次数: 0