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on Transport Economics |
| By: | Correa-Jullian, Camila PhD; D'Agostino, Mollie C. MS; Mosleh, Ali PhD; Ma, Jiaqi PhD |
| Abstract: | To improve the safety of automated vehicles, this study developed a mathematical model to indicate the degree to which certain traffic conditions, driver characteristics, and behaviors of an automated driving system (ADS) affect the probability of a driver safely taking over control in a level 3 ADS to avoid a potential crash. (A level 3 ADS requires the driver to intervene when the ADS cannot safely handle a situation.) Experiments in which 50 participants used a driving simulator informed the model development. The presence of a warning signal from the ADS telling the driver to intervene significantly reduced collision probability, improved driver reaction time, and increased the safety margin between the study vehicle and the vehicle in front of it. Traffic complexity—the number of nearby vehicles—increased the probability of hard-braking, tailgating, and steering variability, and it increased the drivers’ perceived workload and distrust of automation. The absence of a driver warning from the ADS interacted with higher traffic complexity, so that their combination greatly increased collision probability. These findings indicate that driver warnings provide measurablesafety benefits and will be used to refine the model and examine the effects of the design and timing of warnings. |
| Keywords: | Engineering, Automated vehicle control, Level 3 driving automation, Autonomous vehicle handover, Driving simulators, Crash avoidance systems |
| Date: | 2026–10–01 |
| URL: | https://d.repec.org/n?u=RePEc:cdl:itsdav:qt87x5w38t |
| By: | Pan, Dangran; Xue, Zhiyuan; Shahriar, Muhammad Shajid |
| Abstract: | This study examines short-term freeway traffic instability using station-level 5-minute data from the California Performance Measurement System for Caltrans District 4. The dataset covers April 7, 2026. After restricting the sample to retained mainline observations, rolling 15-minute measures of mean speed, speed variability, occupancy variability and net speed change were constructed for 652, 080 station-time observations. An instability-congestion proxy state was defined as the joint occurrence of speed variability at or above its 75th percentile and mean speed at or below its 25th percentile. An exploratory logistic classification model was then used to describe how the four traffic measures separate observations assigned to this proxy state. Occupancy variability and positive net speed change were associated with higher classification odds. However, mean speed and speed variability partly define the outcome and their coefficients are therefore definitional rather than independent evidence of safety effects. In addition, the model does not account for dependence among repeated observations from the same detector station. The results demonstrate a transparent approach for screening unstable congestion from high-resolution detector data but do not establish crash probability or causal safety effects. Validation against observed crashes, longer observation periods and models accounting for station-level and temporal dependence are required before operational deployment. |
| Keywords: | Engineering, Freeway Traffic Instability, PeMS, Speed Variability, Occupancy Variability, Traffic Congestion, Freeway Operations, Rolling-Window Analysis, Logistic Regression, Caltrans District 4, San Francisco Bay Area. |
| Date: | 2026–10–06 |
| URL: | https://d.repec.org/n?u=RePEc:cdl:itsrrp:qt2wn1n8b8 |
| By: | Filip Premik (Department of Economics, Monash University, Melbourne, Australia; Group for Research in Applied Economics (GRAPE), Warszawa, Poland); Dan Yu (Department of Resource Economics and Environmental Sociology, University of Alberta, Edmonton, Canada) |
| Abstract: | We study how heterogeneity in capital inputs affects firm performance. Drawing on detailed data on municipal bus fleets in Poland, we exploit plausibly exogenous variation generated by public procurement and nationally coordinated sales behavior of bus manufacturers to identify the causal effects of variety in fleet composition across brands and other technical dimensions. More heterogeneous fleets exhibit lower vehicle utilization and, for a fixed level of output, require more units of capital and generate higher costs. Our results emphasize that the productive capacity of capital depends on its internal structure, not only on its aggregate quantity or value. |
| Keywords: | Heterogeneous capital; capital utilization; productivity; fleet composition; organization of production |
| JEL: | D24 L23 L62 |
| Date: | 2026 |
| URL: | https://d.repec.org/n?u=RePEc:fme:wpaper:121 |
| By: | Carballido Cerqueiro, María; Carro, Jesús M.; Siotis, Georgios |
| Abstract: | This paper aims to better understand competitive rivalry in the US airline industry over the last 25 years. First, it contributes to a better understanding of the procompetitive "Southwest effect" over the period 2000-2025. We show that this effect can clearly be identified during the first part of our sample period, but disappears circa 2016, when Southwest culminated a process of strategic re-orientation and appears to have started behaving like legacy carriers. Second, we find that Southwest presence on a route flattened the relationship between air fares and Multimarket Contact (MMC) until the mid-2010s; since then, the two groups of routes have converged. Third, we document that the effect of MMC on fares has diminished over time. We conjecture that this may be due to increased concentration and symmetry among major players. Fourth, our results indicate that a linear specificationto identify the relationship between MMC and fares may be adequate until2007. This is no longer the case afterwards: the data point to a non-monotonic U/V-like shape, first on routes with Southwest and, from 2016, on all routes. Fifth, the pandemic seems to have led to a temporary breakdown in tacit collusion, but only on routes where Southwest was not present; once the COVID-19 crisis ended, the long-run evolution of the MMC-fare relationship resumed. |
| Keywords: | Southwest effect; Multimarket contact; Airline industry; Demand shock; Pandemic |
| Date: | 2026–10–07 |
| URL: | https://d.repec.org/n?u=RePEc:cte:werepe:50949 |
| By: | Javier Donna (University of Miami-Rimini Center for Economic Analysis); E. Mina Guler (University of Miami) |
| Abstract: | A federal court blocked JetBlue’s acquisition of Spirit Airlines in January 2024 to protect consumers who relied on Spirit’s low fares. Spirit failed anyway and ceased operations in May 2026. We ask whether the prohibition protected consumers. Using DB1B data for 2022–2025, we estimate the effect of Spirit’s exit across the 1, 427 routes it served. The 5th and 10th percentile fares rise by 8.6 and 5.8 log points; mean and median fares are unaffected. Where a carrier entered, the bottom is unaffected and mean fares fall. Theharm comes from exit without replacement, which entry policy does not reach. |
| Keywords: | Ultra-low-cost carriers; Entry and exit; Merger enforcement; Failing firm defense; Fare distribution; Antitrust |
| JEL: | L93 L41 L13 L51 K21 |
| Date: | 2026–10 |
| URL: | https://d.repec.org/n?u=RePEc:aoz:wpaper:409 |