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on Transport Economics |
| By: | Han, Xiao PhD; Ma, Rui PhD; Zhang, H. Michael PhD |
| Abstract: | Traffic signals, while serving an important function to coordinate vehicle movements through intersections, also cause frequent stops and delays, particularly when they are not properly timed. Such stops and delays contribute to significant amount of fuel consumption and greenhouse gas emissions. The recent development of connected and automated vehicle (CAV) technology provides new opportunities to enable better control of vehicles and intersections, that in turn reduces fuel consumption and emissions. In this paper, we propose platoon-trajectory-optimization (PTO) to minimize the total fuel consumption of a CAV platoon through a signalized intersection. In this approach, all CAVs in one platoon are considered as a whole, that is, all other CAVs follow the trajectory of the leading one with a time delay and minimum safety gap, which is enabled by vehicle to vehicle communication. Moreover, the leading CAV in the platoon learns of the signal timing plan just after it enters the approach segment through vehicle to infrastructure communication. We compare our PTO control with the other two controls, in which the leading vehicle adopts the optimal trajectory (LTO) or drive with maximum speed (AT), respectively, and the other vehicles follow the leading vehicle with a simplified Gipps’ car-following model. Furthermore, we extend the controls into multiple platoons by considering the interactions between the two platoons. The numerical results demonstrate that PTO has better performance than LTO and AT, particularly when CAVs have enough space and travel time to smooth their trajectories. The reduction of travel time and fuel consumption can be as high as 40% and 30% on average, respectively, in the studied cases, which shows the great potential of CAV technology in reducing congestion and negative environmental impact of automobile transportation. |
| Keywords: | Engineering, Connect vehicles, autonomous vehicles, traffic platooning, fuel consumption, vehicle trajectories, trajectory controld |
| Date: | 2019–06–01 |
| URL: | http://d.repec.org/n?u=RePEc:cdl:itsdav:qt00d6591g&r=all |
| By: | Jenn, Alan |
| Abstract: | Integrating electric vehicles (EVs) into vehicle fleets deployed by transportation network companies (TNCs; e.g., Uber and Lyft) is a particularly promising way to realize the benefits of vehicle electrification, due to the greater average miles traveled and passenger occupancy of TNC fleets. In this report, the researcher examines EV use in TNC fleets from 2016 through 2018. They leverage novel datasets from TNCs as well as from charging service providers (e.g., Chargepoint and EVGo) to analyze charging and use patterns of EVs within TNC fleets. These insights allow the researcher to quantify the emissions benefits of EV use within TNC fleets, assess the capability of EVs to perform TNC services, and understand the effects of EV use within TNC fleets on the charging behavior of non-TNC EVs. Findings show that the emission benefits of electrifying a vehicle in a TNC fleet are nearly three times greater than the benefits from electrifying a privately-owned vehicle. View the NCST Project Webpage |
| Keywords: | Engineering, Electric vehicle, transportation network company, emissions, fleet, charging, electrification |
| Date: | 2019–08–01 |
| URL: | http://d.repec.org/n?u=RePEc:cdl:itsdav:qt15s1h1kn&r=all |
| By: | Florin Mihai (Alexandru Ioan Cuza University of Iași [Romania]); Mihail Eva (CITERES - Cités, Territoires, Environnement et Sociétés - Université de Tours - CNRS - Centre National de la Recherche Scientifique); Alina-Violeta Munteanu |
| Abstract: | Between 1990 and 2015, the annual global amount of CO 2 emission generated by transport has increased by 68%, from around 4.6 GtCO 2 to around 7.7 GtCO 2. Technological advances towards eco-friendly vehicles and policy incentives promoting environmental-friendly modes of transport have thus been offset by economic growth and increasing mobility. This study questions the relationship between economic growth and sustainability performance of transport sector. It adds to the literature new insights concerning recent trends in the relationship between gross domestic product and various aspects of transport sustainability such as carbon footprint, carbon intensity and transport safety. A particular attention is given to discussing the emerging issues of "carbon inequality" and the role of political entities that contribute most to global CO 2 emissions, such China, USA and the EU. Finally, this study adds to the literature a composite index of transport sustainability performance and explores between-country inequalities in terms of sustainability performance. |
| Keywords: | road fatalities,CO 2 emissions,environmental impact,OECD countries,carbon footprint,carbon inequality |
| Date: | 2019–06–28 |
| URL: | http://d.repec.org/n?u=RePEc:hal:journl:hal-02196197&r=all |
| By: | Christopher Severen; Arthur A. van Benthem |
| Abstract: | An individual’s initial experiences with a common good, such as gasoline, can shape their behavior for decades. We first show that the 1979 oil crisis had a persistent negative effect on the likelihood that individuals that came of driving age during this time drove to work in the year 2000 (i.e., in their mid 30s). The effect is stronger for those with lower incomes and those in cities. Combining data on many cohorts, we then show that large increases in gasoline prices between the ages of 15 and 18 significantly reduce both (i) the likelihood of driving a private automobile to work and (ii) total annual vehicle miles traveled later in life, while also increasing public transit use. Differences in driver license age requirements generate additional variation in the formative window. These effects cannot be explained by contemporaneous income and do not appear to be only due to increased costs from delayed driving skill acquisition. Instead, they seem to reflect the formation of preferences for driving or persistent changes in the perceived costs of driving. |
| Keywords: | formative experiences, preference persistence, path dependence, driving behavior, gasoline price |
| JEL: | D12 D90 L91 Q41 R41 |
| Date: | 2019 |
| URL: | http://d.repec.org/n?u=RePEc:ces:ceswps:_7757&r=all |
| By: | Flueckiger, Matthias; Hornung, Erik; Larch, Mario; Ludwig, Markus; Mees, Allard |
| Abstract: | We show that the creation of the first integrated pan-European transport network during Roman times influences economic integration over two millennia. Drawing on spatially highly disaggregated data on excavated Roman ceramics, we document that interregional trade was strongly influenced by connectivity within the network. Today, these connectivity differentials continue to influence cross-regional firm investment behaviour. Continuity is largely explained by selective infrastructure routing and cultural integration due to bilateral convergence in preferences and values. Both plausibly arise from network-induced history of repeated socio-economic interaction. We show that our results are Roman-connectivity specific and do not reflect pre-existing patterns of exchange. |
| Keywords: | business links; cultural similarity; economic integration; Roman trade; transport network connectivity |
| JEL: | F15 F21 N73 O18 R12 R40 |
| Date: | 2019–07 |
| URL: | http://d.repec.org/n?u=RePEc:cpr:ceprdp:13838&r=all |
| By: | Shilling, Fraser; Denney, Cameron; Waetjen, David |
| Abstract: | States increasingly maintain databases of wildlife-vehicle conflict (WVC), including locations of carcasses and crashes involving animals. Once these data are collected, a common and expensive barrier before they can be used in safety and environmental planning is identification of “hotspots” of incidents (here defined as locations of high-rates and/or statistically-significant clusters). In this project, we developed a web-based analytical environment that state DOTs can use to automate certain analyses of WVC hotspots in order to inform planning to improve driver and wildlife safety. Specifically, we coordinated with staff from 3 states: Idaho, Nevada, and Maine, and used data that we had for California to develop the pilot automated hotspots analysis tool. We tested several methods for representing both density and statistically-significant clustering of WVC events. These were implemented in the statistical package R and driven by scripts that can operate in the project web-system. Testing was conducted using California data while other states prepared/delivered their data. We developed hotspots analyses for California, Maine, Idaho, and Nevada based upon their input. We prepared a web-system to operate the tool (https://roadecology.ucdavis.edu/hotspots), that DOT staff from 13 states used so far with their own data. |
| Keywords: | Engineering, Life Sciences, Animals, Crash data, Data analysis, High risk locations, Traffic crashes, Traffic safety, Wildlife |
| Date: | 2019–07–01 |
| URL: | http://d.repec.org/n?u=RePEc:cdl:itsdav:qt8h24v43z&r=all |
| By: | Mogens Fosgerau (DTU - Technical University of Denmark [Lyngby]); Julien Monardo (ENS Cachan - École normale supérieure - Cachan, CREST - Centre de Recherche en Économie et Statistique - ENSAI - Ecole Nationale de la Statistique et de l'Analyse de l'Information [Bruz] - X - École polytechnique - ENSAE ParisTech - École Nationale de la Statistique et de l'Administration Économique - CNRS - Centre National de la Recherche Scientifique); André de Palma (X-DEP-ECO - Département d'Économie de l'École Polytechnique - X - École polytechnique) |
| Abstract: | This paper proposes an empirical model of inverse demand for differentiated products: the Inverse Product Differentiation Logit (IPDL) model. The IPDL model generalizes the commonly used nested logit model to allow richer substitution patterns, including complementarity. Nevertheless, the IDPL model can be estimated by two-stage least squares using aggregate data. We apply the IDPL model to data on ready-to-eat cereals in Chicago in 1991-1992, and find that complementarity is pervasive in this market. We then show that the IPDL model belongs to a wider class of inverse demand models in which products can be complements, and which is sufficiently large to encompass a large class of discrete choice demand models. We establish invertibility for this wider class, thus extending previous results on demand inversion. |
| Keywords: | Demand estimation,Demand invertibility,Differentiated products,Discrete choice,Nested logit,Random utility,Representative consumer |
| Date: | 2019–07–15 |
| URL: | http://d.repec.org/n?u=RePEc:hal:wpaper:hal-02183411&r=all |
| By: | Dong Cheng; Mario J Crucini; Hyunseung Oh; Hakan Yilmazkuday |
| Abstract: | The beginning of the twentieth century provides a unique opportunity to explore the interaction of rapid technological progress and trade barriers in shaping the worldwide diffusion of a new, highly traded good: the automobile. We scrape historical data on the quantity and value of passenger vehicles exported from the United States to other destination countries, annually from 1913 to 1940. We model the rise of US automobile from global obscurity toward a level dependent upon the extent of long-run pass-through of US prices into destination markets and destination GDP per capita. The results based on a diffusion model with CES preferences and non-unitary income elasticity shows that 62% of the gap in diffusion levels between the U.S. and the rest of the world is due to price frictions such as markups, tariffs, and trade costs, while the remaining 38% is due to income effects. |
| Keywords: | Product Diffusion, Automobile, International Trade, Wedge Accounting |
| JEL: | F10 L62 N60 N70 O33 |
| Date: | 2019–08 |
| URL: | http://d.repec.org/n?u=RePEc:een:camaaa:2019-58&r=all |
| By: | Fos, Vyacheslav; Hamdi, Naser; Kalda, Ankit; Nickerson, Jordan |
| Abstract: | This paper shows that the introduction of the "gig-economy" changes the way employees respond to job loss. Using a comprehensive set of Uber product launch dates and employee-level data on job separations, we show that laid-off employees with access to Uber are less likely to apply for UI benefits, rely less on household debt, and experience fewer delinquencies. Our empirical strategy is based on a triple difference-in-difference empirical model, comparing the difference in outcome variables 1) pre- and post-layoff, 2) before and after Uber enters a market, and 3) between workers with and without the ability to participate on the ride-sharing platform (car-owners inferred from auto credit histories). In support of our identification strategy, we find no apparent pre-existing difference in outcomes in the months leading up to Uber's entry into a market. Moreover, the effects are severely attenuated for workers with an auto lease, for whom the viability of participating on the ride-sharing platform is significantly reduced. Overall, our findings show that the introduction Uber had a profound effect on labor markets. |
| Keywords: | credit delinquencies; gig-economy; Household Debt; labor markets; Unemployment insurance |
| JEL: | D10 E24 H53 J23 J65 |
| Date: | 2019–07 |
| URL: | http://d.repec.org/n?u=RePEc:cpr:ceprdp:13885&r=all |