This thesis presents a methodology for conducting logistic regression modeling of trip and household information obtained from household travel surveys and vehicle trip information obtained from global positioning systems (GPS) to better understand the trip underreporting that occurs. The methodology presented here builds on previous research by adding additional variables to the logistic regression model that might be significant in contributing to underreporting, specifically, trip purpose. Understanding the trip purpose is crucial in transportation planning because many of the transportation models used today are based on the number of trips in a given area by the purpose of a trip. The methodology used here was applied to two study areas in Texas, Laredo and Tyler-Longview. In these two study areas, household travel survey data and GPS-based vehicle tracking data was collected over a 24-hour period for 254 households and 388 vehicles. From these 254 households, a total of 2,795 trips were made, averaging 11.0 trips per household. By comparing the trips reported in the household travel survey with those recorded by the GPS unit, trips not reported in the household travel survey were identified. Logistic regression was shown to be effective in determining which household- and trip-related variables significantly contributed to the likelihood of a trip being reported. Although different variables were identified as significant in each of the models tested, one variable was found to be significant in all of them - trip purpose. It was also found that the household residence type and the use of household vehicles for commercial purposes did not significantly affect reporting rates in any of the models tested. The results shown here support the need for modeling trips by trip purpose, but also indicate that, from urban area to urban area, there are different factors contributing to the level of underreporting that occurs. An analysis of additional significant variables in each urban area found combinations that yielded trip reporting rates of 0%. Similar to the results of Zmud and Wolf (2003), trip duration and the number of vehicles available were also found to be significant in a full model encompassing both study areas.

This thesis presents a methodology for conducting logistic regression modeling of trip and household information obtained from household travel surveys and vehicle trip information obtained from global positioning systems (GPS) to better understand the trip underreporting that occurs. The methodology presented here builds on previous research by adding additional variables to the logistic regression model that might be significant in contributing to underreporting, specifically, trip purpose. Understanding the trip purpose is crucial in transportation planning because many of the transportation models used today are based on the number of trips in a given area by the purpose of a trip. The methodology used here was applied to two study areas in Texas, Laredo and Tyler-Longview. In these two study areas, household travel survey data and GPS-based vehicle tracking data was collected over a 24-hour period for 254 households and 388 vehicles. From these 254 households, a total of 2,795 trips were made, averaging 11.0 trips per household. By comparing the trips reported in the household travel survey with those recorded by the GPS unit, trips not reported in the household travel survey were identified. Logistic regression was shown to be effective in determining which household- and trip-related variables significantly contributed to the likelihood of a trip being reported. Although different variables were identified as significant in each of the models tested, one variable was found to be significant in all of them - trip purpose. It was also found that the household residence type and the use of household vehicles for commercial purposes did not significantly affect reporting rates in any of the models tested. The results shown here support the need for modeling trips by trip purpose, but also indicate that, from urban area to urban area, there are different factors contributing to the level of underreporting that occurs. An analysis of additional significant variables in each urban area found combinations that yielded trip reporting rates of 0%. Similar to the results of Zmud and Wolf (2003), trip duration and the number of vehicles available were also found to be significant in a full model encompassing both study areas.

National statistics regarding subsidized commuting suggest that employer-based transit subsidies may be inaccessible to the vast majority of the working poor. My main purpose with this study is to increase our understanding of employer-based transit subsidies from a transport justice perspective. I apply the theory of transport justice developed by Karel Martens to evaluate whether the provision of transit subsidies varies significantly by income, and whether the subsidies are significantly associated with accessibility as measured by daily trip levels. I use worker-level data from household travel surveys for 10 of the 22 largest MPOs in the U.S., organized into 7 cases: 1) Atlanta; 2) Baltimore and Washington, DC; 3) Denver; 4) Los Angeles and San Diego; 5) New York and Newark; 6) Philadelphia; and 7) San Francisco. In each of the 7 cases, the odds of being offered a transit subsidy were significantly lower for workers in the 1st income quintile compared to workers in the 4th and 5th income quintiles, even after controlling for other relevant worker and employer characteristics. I found a lack of evidence, in most cases, that transit subsidies are significantly associated with accessibility, both in terms of daily trip levels for low-income workers and daily trip differentials between income groups. Given my finding that low-income workers are the least likely to have access to employer-based transit subsidies, policymakers may consider reform alternatives, such as commuter benefit ordinances, a refundable tax credit for commuting expenses, or alternatives such as income- and location-based subsidies for transit that may support all trip purposes. I hope this study will serve as a reference for policymakers deliberating commuter benefit reforms as well as strategies to support affordable access to opportunities for the working poor. / Ph. D. / National statistics for subsidized commuting suggest employer-based transit subsidies are inaccessible to the majority of the working poor. Using a transport justice theoretical frame, this quantitative study used worker-level data from household travel surveys to evaluate whether employer-based transit subsidies vary by income, and whether the subsidies are associated with accessibility. The data were organized into 7 cases: 1) Atlanta; 2) Baltimore and Washington, DC; 3) Denver; 4) Los Angeles & San Diego; 5) New York and Newark; 6) Philadelphia; and 7) San Francisco. In each of the 7 cases, the odds of being offered a transit subsidy were significantly lower for workers in the 1st income quintile compared to workers in the 4th and 5th income quintiles, even after controlling for other relevant worker and employer characteristics. In most cases, I did not find a significant association between transit subsidies and accessibility. This study may serve as a reference for policymakers deliberating commuter benefit reforms as well as strategies to support affordable access to opportunities for the working poor.

A partir de l'objet automobile, cette thèse propose une réponse en trois temps à la problématique du rôle de la consommation matérielle dans la stratification sociale. Grâce aux caractéristiques originales du bien automobile, l'objectif poursuivi est d'interroger la question de l'homogénéisation des styles de vie dans le contexte de la France contemporaine sous trois rapports : les phénomènes de diffusion de l'automobile, la distribution sociale des caractéristiques de l'équipement, la répartition des coûts engendrés par la voiture. Comment caractériser la diffusion d'un objet symbolique de la consommation de masse et quelles sont les limites à cette diffusion ? Comment sont distribués les biens selon leurs caractéristiques dans l'espace social ? Comment varient les différents coûts de l'automobile parmi les groupes sociaux ? Nous répondons à de telles questions en recourant à une analyse secondaires de deux séries d'enquêtes réalisées par l'Institut National de la Statistique et des Études Économiques : les Enquêtes Nationales Transports réalisées en 1981, 1993 et 2007 ainsi que les enquêtes Budget de famille réalisées en 1985, 1989, 1995, 2001 et 2006. / By using the automobile as a social object, this thesis provides a threefold answer to the problem of the role of material consumption in social stratification. Thanks to the very original nature of automobile, we aim at address the question of the homogenization of lifestyles in contemporary France in three differents aspects : the phenomenons of social diffusion, the distribution of the characteristics of the automobile in social space and the repartition of the internal and external costs of the car. How can we characterize the diffusion of a good symbolic of mass consumption ? Which limits does this diffusion assume ? How are distributed the characteristics of the material goods in social space ?How do the differents costs of the automobile vary among social groups ? We adress theses questions by using secondary analysis of two series of suveys conducted by the French institute of statistics : the National Travel Surveys realized in 1981, 1993 and 2007 and the French Household Expenditure Surveys conducted in 1985, 1989, 1995, 2001 and 2006.

There is a growing recognition of the role that walking and cycling can make in reducing traffic congestion and air pollution whilst also contributing to improved personal health and wellbeing. While studies suggest that infrastructure is required to promote walking and cycling, there is a lack of evidence at the micro level on how interventions aimed at improving connectivity for walking and cycling influence travel behaviour and whether they promote a modal shift away from short car journeys. The aim of this study was to investigate the extent to which the implementation of a high quality traffic free route, delivered by a recent programme targeted at everyday walking and cycling in the UK - the Sustrans Connect2 Programme - influenced individuals' day-to-day travel decisions, changed the spatial and temporal nature of their journeys and impacted on overall carbon emissions from motorised travel. To achieve this aim an in-depth longitudinal panel study of a community of residents living next to a totemic Connect2 scheme in Penarth, Cardiff, was conducted. A panel of purposively selected participants (N=50) were interviewed and asked to record their travel behaviour using personal GPS devices and travel diaries over two seasonally matching 7-day time periods in 2011 and 2012. This novel GPS based mixed-method approach provided a detailed account of participants' travel behaviour in the local area (n=2664 journeys) and a comprehensive understanding of how, why and for whom the Connect2 intervention was likely to influence travel behaviour and the longevity of effects. The findings revealed that participants used the new Connect2 scheme regularly during the period of the study (36% in 2011; 26% in 2012); however, the new scheme was likely to have a greater impact for recreational journeys rather than for everyday travel. Spatial data provided new insights into the complexities of walking behaviour and factors influencing cycling for everyday travel or recreation, including route choice decisions, destinations where activities were conducted and the role of the new Connect2 infrastructure in supporting this. Further findings support the potential of active travel in replacing short car trips (20%) and its impact on carbon emissions from personal travel (4.9% among the study sample). However, results suggest that the new Connect2 scheme alone was unlikely to promote a significant change in travel behaviour and carbon emissions from (displaced) car journeys. The study contributes to the debate on the effectiveness of interventions targeted at promoting walking and cycling and the importance of wider infrastructural improvements that may be required to encourage their wider uptake. The combination of methods for data collection developed and employed in this study also helps to inform future travel behaviour research.

No description available.

<p dir="ltr">This research evaluates shared mobility services in the United States, focusing on e-scooter sharing, bike-sharing, and ride-hailing in various urban settings. It aims to understand public and user perceptions, usage patterns, and the impact of urban design on these services. Key research questions include the differences in usage around campuses, public perceptions of shared mobility, future usage intentions post-COVID-19, and the influence of bike lane construction on shared mobility. The study uses survey data and various analytical methods to provide insights for policymakers and operators, introducing the CYCLES framework to enhance shared mobility systems and promote sustainable transportation solutions.</p>

Les travaux de cette thèse visent la connaissance et la compréhension de l'articulation temporelle des mobilités individuelles (quotidiennes, de weekend et de longue distance) en France selon les localisations résidentielles, par taille d'aire urbaine et position par rapport au centre du bassin, via l'élaboration d'un diagnostic annuel en termes d'émission de CO2 afin d'éclairer la question du réchauffement climatique. A la description méthodologique de l'outil, s'appuyant sur les données de l'Enquête Nationale Transports et Déplacements 2007- 2008, succède la présentation de certains résultats marquants, déclinant la répartition de ces émissions selon les lieux d'habitat: Au delà des premières analyses descriptives, une caractérisation typologique des comportements de mobilité a abouti à quatre profils-types selon les budgets d'émissions de CO2 sur ces trois segments temporels de la mobilité. Chacun de ces comportements-types n'est pas uniquement repérable (ni uniforme) dans un seul type d'espace. Un certain « effet barbecue » est visible mais il n'est sans doute pas suffisamment fort pour pouvoir confirmer que les habitants des (grands) centres villes ruinent nécessairement durant le weekend leurs comportements plutôt vertueux en semaine grâce à l'utilisation de modes moins polluants. Les études de cas selon le genre, les grands voyageurs (grands pendulaires ou transcontinentaux), et certains motifs de déplacements (achat, loisirs), sont des coups de projecteurs qui ont apporté des résultats complémentaires. Enfin, l'analyse des taux d'occupation sur l'exemple de l'automobile pour des déplacements locaux a montré qu'un meilleur remplissage des véhicules est un facteur important de l'efficacité énergétique (et donc du CO2) des déplacements. / My thesis concern is about knowledge and in depth-understanding of the annual distribution of individual mobility in France (distinguishing daily, weekend and long distance trips) according to the residential locations (by category of urban areas) via the development of an annual CO2 emissions assessment, to address the issue of climate change. After a brief methodological description of the tool, using the dataset of the most recent French National Transport Survey (2007-2008), the paper presents some typical results, declining the distribution of CO2 emissions due to this mobility according to the zone of residence: beyond the initial descriptive analyses, a cluster analysis of mobility behavior results in four profiles of mobility according to the CO2-emissions budgets on these three time segments of mobility. It shows that each type of mobility behavior is not available (nor uniform) in only one type of space. A "cocooning effect" can be detected but it is probably not strong enough to confirm that the citizens of (large) city centers during the weekend necessarily ruin their rather virtuous behavior on week days through the use of less polluting modes. Case studies by gender, frequent travelers (pendulous or transcontinental), and some travel purposes (e.g. shopping, leisure) provide additional results. Finally, the analysis of occupancy rates of the car for local travel shows, that more passengers in a vehicle is an important factor for its energy efficiency (and therefore CO2) due to mobility.