Vehicle Ownership

""Bus Rapid Transit (BRT) has become popular as a means to provide reliable, non-automobile-based mobility and alleviate impacts of rising traffic congestion in cities around the world. To date, however, there is little empirical evidence supporting BRT’s potential to meet these objectives, and limited understanding of the urban form conditions necessary to support BRT. This research improves knowledge of BRT’s potential as an alternative to vehicle ownership at the household level and provides new evidence of the role of urban form in supporting transit investment.

I use a difference-in-differences research design to examine the changes in vehicle ownership and non-car mobility from before to after implementation of Bogotá, Colombia’s TransMilenio BRT system. With respect to vehicle ownership, my results indicate access to TransMilenio’s main trunk system is negatively related to the odds of vehicle ownership for higher wealth households. Among lower wealth households, access to the main trunk system is not related to vehicle ownership except in neighborhoods with urban forms that are supportive of walking, bicycling, and transit use. Furthermore, I find access to TransMilenio’s feeder system (which brings passengers from peripheral neighborhoods into the main trunk system) is associated with an unexpected increase in the odds of vehicle ownership. This increase may be due not necessarily to the introduction of the feeder service itself, but to concurrent policies of upgrading roadways and investing in housing stock in feeder served neighborhoods. Regardless of the cause, however, the increase in vehicle ownership among lower wealth, feeder-served households appears to be reversed in neighborhoods where urban form supports transit and non-motorized travel. This finding suggests the importance of a concerted effort to coordinate transit interventions with urban development policies that support those interventions, particularly in lower wealth neighborhoods.

I found no evidence TransMilenio access was significantly related to non-car mobility (tour frequency, travel purpose diversity, and vehicle independence) among lower wealth car-less households. Relationships between mobility and urban form were ambiguous and inconsistent. I attribute these results to limitations in the available techniques for measuring mobility. I describe approaches to improve the validity and reliability of these techniques in future research.""

Using responses to a knowledge–attitudes–behavior questionnaire administered in the Sacramento, California metropolitan region, the effects of environmental knowledge and environmental attitudes on the numbers and types of vehicles owned per household, annual vehicle miles traveled, and fuel consumption are assessed. The results indicate that households with pro-environmental attitudes own fewer and more fuel-efficient vehicles, drive them less, and consequently consume less fuel than do the households of respondents without pro-environmental attitudes. The households of respondents who know more about the environmental impacts of owning and using vehicles own more fuel-efficient vehicles, but environmental knowledge is not statistically significant in relation to numbers of vehicles owned, miles driven, or fuel consumption.

Abstract: The culmination of new vehicle technology, greater competition in energy markets, and government policies to reduce pollution and energy consumption will result in changes in the personal vehicle marketplace. Understanding the impact of these factors, through vehicle ownership modeling, is critical for achieving environmental and economic goals. This study focuses on analyzing future demand for battery electric, hybrid electric, plug-in hybrid electric, alternative fuel, and gasoline vehicles over the short to medium term. To do ...

In the near future, the culmination of new vehicle technologies, greater competition in the energy markets, and government policies to fight pollution and reduce energy consumption will result in changes in the United States' vehicle marketplace. This project proposes to create a stated preference (SP) survey along with discrete choice models to predict future demand for electric, hybrid, alternative fuel, and gasoline vehicles. The survey is divided into three parts: socioeconomics, revealed preference (RP), and SP sections. The socioeconomics portion asks respondents about themselves and their households. The RP portion asks about household's current vehicles. The SP section presents respondents with various hypothetical scenarios over a future five-year period using one of three game designs. The designs correspond to: changing vehicle technology, fuel pricing and availability, and taxation policy. With these changes to the vehicle marketplace, respondents are asked whether they will keep or replace their current vehicles and if he will purchase a new vehicle and its type. To facilitate the design and administering of the survey, a web survey framework, JULIE, was created specifically for creating stated preference surveys. A preliminary trial of the survey was conducted in September and October 2010 with a sample size of 141 respondents. Using the SP results from this preliminary trial, a multinomial logit model is used to estimate future vehicle ownership by vehicle type. The models show that the survey design allows for estimation of important parameters in vehicle choice.

The culmination of new vehicle technology, greater competition in energy markets, and government policies to reduce pollution and energy consumption will result in changes to the personal vehicle marketplace. To measure future vehicle preferences, stated preference (SP) surveys have been the dominant approach. Prior research has been limited to a narrow focus of accelerating respondents' hypothetical next vehicle purchasing decisions without mimicking the influence of the marketplace on these decisions. To explore marketplace influences, this study proposes to use a novel SP survey design to analyze vehicle purchasing behavior in a dynamically changing marketplace through the use of dynamic attributes and a 6-year hypothetical time window. The survey is divided into three parts: household characteristics, current vehicles, and SP. The SP section presents respondents with various hypothetical scenarios annually over a future 6-year period with one of three experiments. The experiments correspond to changing vehicle technology, fueling options, and taxation policy. Between scenarios, the vehicle, fuel, and policy attributes dynamically change to mimic marketplace conditions. A pilot web-based survey was performed during fall 2010. Mixed logit models showed that individuals responded in behaviorally realistic ways and that the survey design allowed for estimation of important parameters in vehicle choice. Respondents were able to depreciate their vehicles over the 5-year hypothetical period and place trade-offs on the features of vehicles and fuel types. The insights from the survey are also used to suggest refinements to the survey methods and areas for further research.

Though most Americans hold pro-environmental attitudes, an attitudes-behavior gap exists with respect to vehicle ownership. Significant constraints appear to prevent most people with environmental concerns from buying smaller, more fuel-efficient, less-polluting vehicles. But researchers have only a simplistic understanding of what those constraints are and how individuals describe and react to them. This study explored these barriers in depth through a series of focus group discussions with 36 residents of the Sacramento, California, metropolitan region who held pro-environmental attitudes.

Analysis of the focus group conversations revealed that the features of vehicles currently on the market, family and work responsibilities, residential choices, and routines and preferences all constrained participants’ vehicle purchase choices to ones which, more often than not, poorly reflect their environmental attitudes. The group conversations also revealed serious misunderstandings about the environmental impacts of owning and using vehicles that make it difficult for many to accurately assess their alternatives.

For some participants, environmental concerns are unlikely to influence future vehicle purchase decisions, even if constraints were removed altogether; other priorities have taken and will take precedence over the environmental impacts of their choices. But for many participants, strategies to remove or weaken the identified constraints to owning smaller and more fuel-efficient vehicles could lead them to choose vehicles that would reduce their resource and energy consumption for personal transportation. Further research with a larger pool of subjects is needed to confirm whether the focus group findings apply to the larger population.

"Abstract. In addressing various policy problems, deciding which policy measure to start with given the range of measures available is challenging and essentially involves a process of ranking the alternatives, commonly done using multicriteria decision analysis (MCDA) techniques. In this paper a new methodology for analysis and ranking of policy measures is introduced which combines network analysis and MCDA tools. This methodology not only considers the internal properties of the measures but also their interactions with other potential measures. Consideration of such interactions provides additional insights into the process of policy formulation and can help domain experts and policy makers to better assess the policy measures and to understand the complexities involved. This new methodology is applied in this paper to the formulation of a policy to increase walking and cycling.

Keywords: policy formulation, network analysis, multiple-criteria decision analysis, transport policy, walking and cycling"