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Using travel data from the Los Angeles region, researches at UCLA and the University of Virginia measured the effects of traffic delays on travel behavior. THeir findings can be used to advocate for the development of "congestion'adapted" places that host a high number of trips evein in the face of intense traffic.

The San Francisco Bay Area regularly experiences some of the most severe traffic congestion in the U.S. This past year both Inrix and the Texas Transportation Institute (TTI) ranked the Bay Area third only to Washington D.C. and Los Angeles in the time drivers spend stuck in traffic. The TTI estimated that traffic congestion cost the Bay Area economy a staggering $3.1 billion in 2014 (Lomax et al., 2015). Such estimates are based on the premise that moving more slowly than free-flow speeds wastes time and fuel, and that these time and fuel costs multiplied over millions of travelers in large urban areas add up to billions of dollars in congestion costs. But while few among us like driving in heavy traffic, do such measures really capture how congestion and the conditions that give rise to it affect regional economies? This study explores this question for the San Francisco Bay Area by examining how traffic congestion is (i) related to a broader and more conceptually powerful concept of access and (ii) how it affects key industries, which are critical to the performance of the region’s economy.

Transportation planning research addresses accessibility from diverse approaches, focusing varyingly on the usability of the transportation system as a whole, a particular mode, the pattern of land uses, or the wherewithal of individuals and communities to make use of those systems. One aspect of accessibility that has received relatively little attention from planners is its cognitive, experiential aspect. Individuals’ activity and travel choices require not just money and time but also information about opportunities in the city. This component of an individual’s accessibility is highly personal but also dependent on the terrain of land uses and transportation options shaped by planners and policymakers. I seek to extend current accessibility research, addressing shortcomings in how the literature deals with individual experience of the city and knowledge. Through a series of empirical analyses of activity patterns and cognitive maps of theLos Angeles region, I explore the factors that shape individual accessibility. The first analysis investigates the spatial nature of personal cities, using the activity spaces of respondents to explore the types of opportunities that different populations within a city can access. The second demonstrates the differences – depending on mode of travel – among individuals’ perceptions of the city, even when location is held constant. The third analysis continues an exploration of the personal city by considering its fundamental components.Overall, the analyses support the relevance of the personal city framework to accessibility research, highlighting in particular that planning interventions are filtered through experiential and cognitive processes. The findings highlight that the accessibility impacts of transportation and land use patterns are felt not just in the instantaneous calculations of a microeconomic choice framework, but also in the long-term, developmental processes of cognition and experience. For urban planners, the implications of this research include evidence of how the built environment can effectively reduce travel while maintaining accessibility and how different transportation modes afford varying levels of functional accessibility. Overall, I find that experience, information, and learning are elements of urban daily life traditionally neglected by planners but with potential to increase opportunity and accessibility for diverse urban populations.

Transportation planning research addresses accessibility from diverse approaches, focusing varyingly on the usability of the transportation system as a whole, a particular mode, the pattern of land uses, or the wherewithal of individuals and communities to make use of those systems. One aspect of accessibility that has received relatively little attention from planners is its cognitive, experiential aspect. Individuals’ activity and travel choices require not just money and time but also information about opportunities in the city. This component of an individual’s accessibility is highly personal but also dependent on the terrain of land uses and transportation options shaped by planners and policymakers. I seek to extend current accessibility research, addressing shortcomings in how the literature deals with individual experience of the city and knowledge. Through a series of empirical analyses of activity patterns and cognitive maps of the Los Angeles region, I explore the factors that shape individual accessibility. The first analysis investigates the spatial nature of personal cities, using the activity spaces of respondents to explore the types of opportunities that different populations within a city can access. The second demonstrates the differences – depending on mode of travel – among individuals’ perceptions of the city, even when location is held constant. The third analysis continues an exploration of the personal city by considering its fundamental components.Overall, the analyses support the relevance of the personal city framework to accessibility research, highlighting in particular that planning interventions are filtered through experiential and cognitive processes. The findings highlight that the accessibility impacts of transportation and land use patterns are felt not just in the instantaneous calculations of a microeconomic choice framework, but also in the long-term, developmental processes of cognition and experience. For urban planners, the implications of this research include evidence of how the built environment can effectively reduce travel while maintaining accessibility and how different transportation modes afford varying levels of functional accessibility. Overall, I find that experience, information, and learning are elements of urban daily life traditionally neglected by planners but with potential to increase opportunity and accessibility for diverse urban populations.

This project conceptually and empirically explores the complex relationships between congestion and accessibility. While congestion alters individual access to opportunities, its effects vary significantly across people, places, and time- variations that reaming relatively understudied. This report begins by proposing a conceptual framework with three components. First, congestion can constrain mobility and thus indirectly reduce accessibility. Second, congestion is associated with agglomeration of activity and with increased accessibility. Finally, congestion in in part a phenomenon of perception and behavior, cognitively altering an individuals choice set of destinations and altering actual access to opportunities. Congestion and individual travel data for the Los Angeles region are sued to explore the localized spatial relationship between congestion and accessibility. As our multifaceted framework suggests, congestion does not have a uniform effect on accessibility, but varies substantially by neighborhood. Our analysis finds that in some neighborhoods congestion appears to be associated with depressed levels of access, as conventional wisdom would suggest. Other neighborhoods, however, appear to be “congestion adapted,” allowing high levels of activity participation despite high levels of congestion. To account for personal characteristics such as income that may influence the spatial analysis, we construct a model of the number of daily trips as a function of an array of personal and household characteristics. Residuals from the model suggest that place-based neighborhood effects explain the relatively higher levels of travel by residents found in the “congestion adapted” neighborhoods.

This project conceptually and empirically explores the complex relationship between congestion and accessibility. While congestion alters individual access to opportunities, its effects vary significantly across people, places, and time - variations that remain relatively understudied. This report begins by proposing a conceptual framework with three components. First, congestion can constrain mobility and thus indirectly reduce accessibility. Second, congestion is associated with agglomerations of activity and with increased accessibility. Finally, congestion is in part a phenomenon of perception and behavior, cognitively altering an individual’s choice set of destinations and altering actual access to opportunities. Congestion and individual travel data for the Los Angeles region are used to explore the localized spatial relationship between congestion and accessibility. As our multifaceted framework suggests, congestion does not have a uniform effect on accessibility, but varies substantially by neighborhood. Our analysis finds that in some neighborhoods congestion appears to be associated with depressed levels of access, as conventional wisdom would suggest. Other neighborhoods, however, appear to be more “congestion adapted,” allowing high levels of activity participation despite high levels of congestion. To account for personal characteristics such as income that may influence the spatial analysis, we construct a model of the number of daily trips as a function of an array of personal and household characteristics. Residuals from the model suggest that place-­‐based neighborhood effects explain the relatively higher levels of travel by residents found in the “congestion adapted” neighborhoods.

Cognitive mapping is central to spatial behavior and decision making. The cumulative process of spatial learning, during which cognitive maps develop primarily through wayfinding and travel experience, affects accessibility by determining whether and how destinations are encoded into one’s cognitive map. In this paper, we examine whether differences in cognitive maps can be explained, in part, by variations in travel mode. To test our hypothesis, we surveyed adults in a low-income Los Angeles neighborhood with relatively low auto use and high transit use. Our data show that variations in cognitive mapping and spatial knowledge do indeed vary between individuals and among groups in systematic ways. Some of these differences are related directly to previous travel experience, including experience with travel modes. We conclude that variations in spatial knowledge can result in radically different levels of “functional accessibility,” despite similar locations, demographics, and other factors commonly thought to influence travel behavior. A better understanding of the complex relationships among spatial cognition and travel can help guide policymakers, planners, and transportation analysts in improving accessibility to employment, services, recreation, and other important destinations.

In this paper we combine theoretical and empirical research on cognitive mapping with our own initial research on the topic to suggest how cognitive mapping might be employed to help us better understand and predict travel behavior, emphasizing how spatial cognition shapes access to opportunity. We argue that the path-based, cumulative process of spatial learning, during which the cognitive map develops primarily through wayfinding and travel experience, affects accessibility by determining whether and how destinations are encoded into a person’s cognitive map. Variations in cognitive mapping, spatial knowledge, and resultant travel behavior can vary between individuals or among groups in systematic ways. Some of these differences are related directly to previous travel experience, including experience with various travel modes. Such variations in spatial knowledge can result in different levels of functional accessibility, despite ostensibly similar locations, demographics, and other factors commonly thought to influence travel behavior.Our initial survey of residents in three Los Angeles neighborhoods suggests that cognitive mapping is indeed influenced by neighborhood and travel mode experience, in addition to demographic characteristics. Such modally constructed cognitive maps, which are likely to vary systematically by both location and socio-economic status, may affect perceptions of activity opportunities in ways that travel behavior researchers are only beginning to understand. To a carless job seeker, job opportunities not easily reached by transit are effectively out of reach and even transparent. Modally constructed cognitive maps, in other words, are key to understanding both travel behavior and accessibility in cities.

Implementing the Personal Responsibility and Work Opportunity Reconciliation Act of 1996 in Los Angeles is a difficult task in part because of the size and diversity of the problem. Los Angeles County -- the unit of government responsible for administering welfare programs -- is one of the largest counties in the country spreading across 4,083 square miles. The Los Angeles County is so large that it comprises its own metropolitan area. The County includes neighborhoods that are both highly urbanized as well as rural, areas of great affluence and areas of concentrated poverty, and neighborhoods that are racially and ethnically diverse.

Recently some US cities have launched pilot driverless shuttle programs, testing driverless shuttles on their roads. Using data collected in April 2020 from respondents in eight US cities, four with pilot driverless shuttle programs and four non-pilot control cities, we investigate the factors associated with residents' attitudes towards driverless shuttles. We use confirmatory factor analysis to construct four latent variables representing respondent attitudes: safety confidence, software security concerns, technology familiarity and interest, and preference for human control. Then, we estimate levels of adoption using a structural equation model-based multigroup analysis. We find that individuals in pilot cities not only demonstrate greater acceptance of driverless shuttle programs but also have different determinants of acceptance compared with those in non-pilot cities. Notably, the effects of local transit access on driverless shuttle acceptance vary between pilot and non-pilot cities. These findings provide early insight into how driverless shuttles may be accepted by the broader population and what factors may influence the effectiveness of driverless shuttles as public transportation over the long term. [ABSTRACT FROM AUTHOR]

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