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Continued advances in information and communications technology are fundamentally changing the structure of the workplace and the organisation of work. Temporary work and self-employment are increasing, while job tenure is declining. This paper examines how these changes may affect both commuting patterns and metropolitan form. The growing number of workers who do not have a long-term attachment to a specific employer are termed 'contingent workers'. Using 1990 Public Use Micro Sample data for the Los Angeles region, the paper compares the commuting and location patterns of contingent and non-contingent workers. Results are quite mixed: residential location patterns do not differ significantly across worker categories, but commute length varies by category, with the self-employed having the shortest commutes.

Discusses the current problems facing the transportation system in Los Angeles, CA, & some potential solutions. Although the extensive highway transportation system & automobile dependency in Los Angeles have allowed rapid growth & promoted business & recreation mobility, these gains have come at the expense of certain social costs: massive air pollution, the time & labor costs of freeway congestion, & the denial of opportunities to the carless. Government solutions to these problems are expansion of the rail system & transportation demand management, eg, carpool matching, sponsored vanpools, preferred parking for carpools, & transit & ride-sharing subsidies. It is argued that these programs are unlikely to succeed unless they are combined with measures that require auto users to pay for the social costs of their usage; such measures would include increases in fuel taxes, registration fees, & road pricing. Further, technology must be used to reduce the social costs of transportation & more flexible alternatives must be offered. 4 Tables, 3 Figures, 23 References. T. Sevier

"A comprehensive update, the fourth edition of this leading text features numerous chapters by new authors addressing the latest trends and topics in the field. The book presents the foundational concepts and methodological tools that readers need in order to engage with today's pressing urban transportation policy issues. Coverage encompasses passenger and freight dynamics in the American metropolis; the local and regional transportation planning process; and questions related to public transit, land use, social equity and environmental justice, energy consumption, air pollution, transportation finance, sustainability, and more." --Provided by publisher.

This paper explores the relationship between land-use patterns and individual mobility from a comparative international perspective. There is a vast literature on US automobile dependence. Major explanatory factors include: transport, housing, land-use and tax policy; per capita incomes; American cultural preferences; national geography; and the spatial structure of US metropolitan areas (itself a result of the first three factors). Emphasising the policy environment, many researchers have cast their analysis in comparative terms, noting the differences in automobile use between European countries and the US. It is argued that US patterns of metropolitan form, with low development densities and dispersed population and employment, reinforce vehicle dependence. In contrast, most European metropolitan areas, with higher densities and more centralised land-use patterns, have lower levels of car use. Stronger controls on land use employed in many European countries are seen as having preserved the compact form of metropolitan areas. These arguments imply significant relationships between land-use patterns and travel behaviour. Using travel diary data from the US and Great Britain, these relationships are compared across the two countries. It is found that differences in daily trips and miles travelled are explained by differences in both the urban form and household income. While the effect of income on daily travel is similar for the US and Great Britain, the effect of density is more pronounced in the US.

Basic to several key issues in current urban economic theory and public policy is a presumption that local imbalances between employment and residential sites strongly influence people's commuting patterns. We examine this presumption by finding the commuting pattern for the Los Angeles region in 1980 which would minimise average commuting time or distance, given the actual spatial distributions of job and housing locations. We find that the amount of commuting required by these distributions is far less than actual commuting, and that variations in required commuting across job locations only weakly explain variations in actual commuting. We conclude that other factors must be more important to location decisions than commuting cost, and that policies aimed at changing the jobs-housing balance will have only a minor effect on commuting.

Americans often look to Southern California as a place where lifestyle trends are born. Now, ironically, the land that has long glorified the car culture is galvanizing commuting behavior and encouraging abstinence from the once-respectable custom of solo driving. The catalyst for this behavioral change is Regulation XV, adopted by the South Coast Air Quality Management District in 1987. Also known as "The Commuter Program," Regulation XV requires all public and private employers (firms, government agencies, schools, hospitals, etc.) with at least 100 employees at any work site to devise commute alternatives for employees and to reduce the number of people driving alone to work.

The paper introduces the concept of the freight landscape: the spatial distribution of freight activity and intensity in a metropolitan area. Using population and employment density information, a freight landscape matrix is calculated for four major metropolitan areas: New York, Los Angeles, Paris and Seoul. Levels of convergence and divergence between population and employment densities are assessed, each characterized by different freight landscapes requiring different city logistics strategies. Results reveal substantial variations between metropolitan areas, which are observed across the respective levels of zonal specialization as well as density changes over distance from central areas.

This research examines the impact of accessibility on the growth of employment centres in the Los Angeles region between 1990 and 2000. There is extensive empirical documentation of polycentricity—the presence of multiple concentrations of employment—in large metropolitan areas. However, there is limited understanding of the determinants of growth of employment centres. It has long been held that transport investments influence urban structure, particularly freeways and airports. Using data on 48 employment centres, the effects are tested of various measures of accessibility on centre employment growth: highway accessibility, network accessibility and two measures of labour force accessibility. Access to airports is also tested. It is found that, after controlling for centre size, density, industry mix, location within the region and spatial amenities, labour force accessibility and network accessibility are significantly related to centre growth. It is concluded that accessibility continues to play an important role in urban spatial structure.

Accessibility is a fundamental concept in theories of metropolitan spatial structure. Urban economic models explain urban structure as a function of access to jobs; accessibility is capitalised into land values, which in turn explain the population distribution. Studies of residential land values show that many factors contribute to the value of a given location: the characteristics of the housing unit, its location with respect to social and environmental amenities, as well as access to jobs, services and other economic opportunities. Empirical studies typically use job access as a proxy for more generalised access to economic activities. However, jobs represent many different activities, from retail shopping to heavy manufacturing, and the value of access to these activities may be positive or negative. In this paper, accessibility measures based on industry sectors have been developed, allowing the separating out of possible different effects. Their impacts are tested on residential land values using data from the Los Angeles region. A multilevel modelling approach is used in order to control for neighbourhood-level attributes common to multiple properties. It is found that the various access measures have different and significant effects on land values, but attributes of the dwelling unit, together with access to the coast, explain most of the variation. The multilevel model is confirmed; there is significant correlation among properties within the same neighbourhood.

AbstractWhile evidence of polycentric urban form is extensive, questions remain regarding the value of agglomeration economies in an information economy, and hence whether polycentricity will persist over time. This paper examines employment spatial structure in four U.S. metropolitan areas between 1990 and 2009. We describe the spatial distribution of employment among centers and non‐center locations across time, examine the persistence of center boundaries, and test for monocentric and polycentric form via density gradient estimations. Results show that the four areas are all polycentric but of different degree. Despite some small fluctuations, metropolitan spatial structure is persistent even in the face of economic shocks in the 2000s: employment centers have not lost their importance and influence in the metro‐wide employment distribution over time.

AbstractWe compare flexible low‐carbon regulations in the transportation sector and their interaction and sequencing with greenhouse gas emissions trading systems in California and Quebec. As momentum builds for greater climate action, it is necessary to better understand how carbon markets and other low‐carbon transportation policies influence one another. First, we demonstrate that emissions trading between California and Quebec has been asymmetric, with linking having little influence on carbon prices from California's perspective but leading to a considerable cost reduction from the point of view of Quebec. Second, we present evidence that Quebec has replicated many of California's low‐carbon transportation policies that promote increased electric vehicle use, where Quebec has an advantage, while deferring to the Canadian federal government with regard to policies that incentivize the production of other low‐carbon transportation fuels. Third, we demonstrate that while the stringency of the policy mix of carbon pricing and flexible transportation regulations has increased over time in both jurisdictions, the stringency of flexible regulations has been more aggressively ratcheted up and is expected to continue to dominate. Overall, our findings suggest that the policy sequence observed in California and Quebec can be attributed to the political economy benefits that the selected instruments confer to governments seeking to move from the middle towards the bottom of the clean technology experience curve. We discuss a number of important research questions and associated hypotheses emanating from our findings, which provide the basis for more in‐depth studies involving a larger universe of cases and economic sectors.