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Emerging micromobility services (e.g., e-scooters) have a great potential to enhance urban mobility but more knowledge on their usage patterns is needed. The General Bikeshare Feed Specification (GBFS) data are a possible source for examining micromobility trip patterns, but efforts are needed to infer trips from the GBFS data. Existing trip inference methods are usually based on the assumption that the vehicle identity (ID) of a micromobility option (e-scooter or e-bike) does not change, and so they cannot deal with data with vehicle IDs that change over time. This paper proposes a comprehensive package of algorithms to infer origin–destination (OD) pairs from GBFS data with static vehicle ID and unlinked trip origins and destinations from GBFS data with resetting and dynamic vehicle ID. The algorithms were implemented in Washington D.C. by analyzing one week (last week of February 2020) of GBFS data published by six vendors, and the inference accuracy of the proposed algorithms are evaluated by R-squared, mean absolute error, and sum absolute error. It is found that the R-squared measure is larger than 0.9 and the MAE measure is less than 2 when the algorithms are evaluated with a 400 m × 400 m grid. The absolute errors are relatively larger in the downtown area, and the inference error is relatively high during early morning and early nighttime. The accuracy of the trip inference algorithms is sufficiently high for most practical applications.

The success of transit systems, traditionally gauged through ridership metrics, must also be assessed via transit accessibility because accessibility to destinations indicates the quality of service that transit provides. Using a structural equation modeling approach, we explain transit accessibility and transit ridership in 2017 for 50 large urbanized areas in the United States as dual outcomes dependent upon population size, urban form, and transit service provision. Also, we examine transit accessibility as a factor that influences transit ridership. We find that transit service provision strongly influences both transit ridership per capita and job accessibility provided by transit. Further, we find that transit accessibility, in turn, offers a moderate boost to transit ridership. Population density results in higher transit accessibility directly by making destinations easier to reach and indirectly by increasing the amount of transit services provided. Other built environment and transit service variables were examined but did not improve the models’ explanatory power. Disaggregating the effects of fixed-guideway (i.e., rail) and non-fixed guideway transit (i.e., buses in mixed traffic), we find that fixed-guideway transit has a more substantial effect on transit accessibility, while non-fixed guideway transit has a larger effect on transit ridership per vehicle mile.

For decades, planners have been drawing circles of a quarter-mile radius to determine easily walkable distances for neighborhood and activity center planning. However, the radius of such “planners’...

Big data applications are attracting increasing interest among urban researchers. One unexplored question is whether the inclusion of big data accessibility indices improves the accuracy of hedonic price models used for residential property valuation. This paper compares a big data index with an index derived from a regional travel demand model developed by local transportation planning agencies and traditional measures of accessibility defined as distances to employment centres. Controls for submarkets and a combined spatial autoregressive and spatial error model are also assessed as tools for capturing the value of location. Using single-family residential transactions from the Miami, Florida, metropolitan area, the study’s main conclusion is that the big data accessibility measure does not add meaningful explanatory or predictive power. In contrast, the spatial autoregressive and error model outperforms the other options considered.

This paper examines the relationship between residential accessibility, i.e., accessibility from a person’s home address, and their likelihood of being in a crash over a three-year period. We explore two potential relationships with accessibility. The first is that persons who live in areas with high destination accessibility may drive less and therefore are less likely to be in vehicular crashes. The second is that persons who live in high vehicle miles traveled (VMT) accessibility areas may be exposed to higher levels of traffic in their regular activity space and therefore may be more likely to be in crashes of all modal types. Examining traffic analysis zones in Knoxville, Tennessee, this research finds some evidence for each of these hypothesized effects. These oppositely directed effects have dominant influence within different travel-time thresholds. The first relationship between destination accessibility and fewer crashes is found to be strongest for 10-minute auto accessibility, whereas the second relationship between VMT accessibility and more crashes is found to occur at 10-minute, 20-minute, and 30-minute thresholds.

•On a per-exclusive-guideway-km basis, LRT capital costs are about double those of BRT.•As BRT guideways become more complex, their guideway costs tend to converge with those of LRT.•The main difference in capital costs between BRT and LRT is in Professional Services.•BRT running on exclusive ROW provides service competitive with that of the automobile and LRT.•LRT support is partly shaped by a common alternative: BRT-lite with little dedicated right of way.

•A method for analyzing the accessibility impact of specific, proposed transportation projects is demonstrated.•Two suites of transportation projects are compared for their 10-year accessibility impacts in San Antonio, Texas.•Land-use forecasts are incorporated to account for how these transportation projects alter future land-use patterns.•Accessibility impacts are compared and contrasted with mobility impacts, with strongly differing outcomes.

While the evidence that the built environment can influence travel behavior to date is fairly robust, the influence of specific, identifiable policy actions is limited. One policy action that can potentially change travel behavior is increasing infill development, particularly if that development is located near the center of a major metropolitan region. This study examines the influence of a large-scale, infill development, Atlantic Station, which opened in 2005 just west of Midtown Atlanta. The study uses propensity scores and differences-in-differences research designs to identify how travel patterns changed for new residents and for existing residents of the area around Atlantic Station, respectively. Atlantic Station reduced vehicle miles traveled and increased alternative mode share for its new residents, but it did not reduce the vehicle miles traveled or increase alternative mode share for the existing residents of the area around Atlantic Station.

Planning organizations are increasingly looking to accessibility measures to understand how well the transportation system provides access to employment opportunities. However, the most common type of job accessibility measure employed in planning practice, the cumulative opportunity measure, considers job supply but overlooks competition for jobs. Therefore, the cumulative opportunity measure may not fully capture workers' access to job opportunity. In this paper, we examine four accessibility measures, two of which account for spatial competition and the other two do not, using the Los Angeles metropolitan area as a case study. We find that measures of competitive accessibility have stronger associations with employment than non-competitive accessibility measures. We examine the relationship between residential accessibility and employment for four separate levels of educational attainment, and we find that competitive measures are especially pertinent for population segments with lower educational attainment. Therefore, we recommend competitive accessibility measures to assess the employment opportunity more accurately.

The concept of accessibility has made inroads into planning practice, largely at the system level. That is, accessibility is measured or modeled for current or future regional transportation and land-use scenarios for evaluation or broad policy guidance. Yet system-level scenarios cannot readily be applied to the project-by-project decision-making that characterizes the majority of transportation and land-use planning decisions. Accessibility evaluation of individual transportation or land-development projects differs from system-level analysis in essential ways and thus requires specialized tools. This article proposes an elasticity-based metric of accessibility that can enable project-level evaluation of land-development projects as an accessibility-based alternative to traffic-impact analysis. The metric is demonstrated for three projects in Ann Arbor, Michigan, USA. The metric is shown to be sensitive to the location of development and capable of distinguishing among the analyzed projects in accessibility terms. Where mobility-based evaluation tends to rank peripheral development highly, the proposed accessibility metric appropriately rates central development as contributing the most to regional accessibility even after accounting for the traffic delay it engenders.

This chapter focuses on nonwork accessibility. Nonwork differs from work accessibility in three important ways. First, people's propensity to travel long distances is significantly greater for work trips than for nonwork trips. The relative shortness of nonwork trips may result from the closeness of available alternative destinations, a resistance to traveling longer distances for nonwork purposes, or some combination of the two. Second, there are frequently good substitutes for nonwork destinations. For example, one grocery store or restaurant may be readily patronized instead of another. Third, nonwork destinations are far more varied and less standardized than work destinations. The chapter then develops a comprehensive index of nonwork accessibility, applies it to large metropolitan regions in the United States, and compares the distribution of nonwork accessibility to work accessibility.

This introductory chapter provides an overview of the shift from mobility to accessibility as the basis for transportation and land-use planning. Reliance on mobility as a guiding planning principle is evidenced in current policy and in the physical form of the built environment in metropolitan areas in the United States and many other countries around the world. When evaluating the performance of a transportation system, the fundamental criterion for success has long been faster vehicle-operating speed. This focus on mobility stands in contrast to a cornerstone of modern transportation planning: the notion that the demand for transportation is largely derived from the demand to reach destinations. If the goal that drives current transportation planning—mobility—differs from the service that people seek from transportation—accessibility—the planning process would tend to overprovide the former and underprovide the latter. Thus, aligning the logic of transportation planning with the core purpose of transportation is about ensuring that people get more of what they want out of the system: access to destinations.

This book flips the tables on the standard models for evaluating regional transportation performance. It argues for an “accessibility shift” whereby transportation planning, and the transportation dimensions of land-use planning, would be based on people's ability to reach destinations, rather than on their ability to travel fast. Existing models for planning and evaluating transportation, which have taken vehicle speeds as the most important measure, would make sense if movement were the purpose of transportation. But it is the ability to reach destinations, not movement per se, that people seek from their transportation systems. While the concept of accessibility has been around for the better part of a century, the book shows that the accessibility shift is compelled by the fundamental purpose of transportation. It argues that the shift would be transformative to the practice of both transportation and land-use planning but is impeded by many conceptual obstacles regarding the nature of accessibility and its potential for guiding development of the built environment. By redefining success in transportation, the book provides city planners, decision makers, and scholars a path to reforming the practice of transportation and land-use planning in modern cities and metropolitan areas.

This concluding chapter highlights the importance of accessibility in transportation planning. Three logics contend for status as transportation planning's conceptual core: mobility, vehicle-kilometers-traveled (VKT) reduction, and accessibility. The transportation-planning field began in the first half of the twentieth century with a mobility orientation. By the end of the century, many planners and researchers had shifted to VKT reductions as the implicit lodestone of progressive action in transportation and land use, a goal that, by the twenty-first century, made its way into some formal policies—though the mobility paradigm remained dominant overall. This book argues for a logic distinct from both of these: an accessibility shift to align transportation and land-use planning with transportation's core purpose. Notwithstanding the challenges it faces in the form of invisibility, accessibility is the only reliable indicator, among the three contenders, of the benefits offered by transportation. This renders both mobility and VKT reduction inadequate as transportation planning's central logic, an inadequacy that can lead to perverse outcomes. The existing mobility paradigm molds transportation and land-use planning at multiple levels and geographic scales and demonstrably shapes metropolitan development. This power suggests that the accessibility shift similarly holds great potential for altering decisions and ultimately the built environment.

This chapter examines different methods to support accessibility-based analysis for both land-development and transportation projects to help forge a closer link between accessibility analysis and applied decision making in planning. Accessibility metrics vary in their measurement approach, purposes, and levels of complexity. Accessibility is normally reported in the form of a score or index to describe the ease of reaching destinations from a place, which allows analysts to compare accessibility from one place to another, or track changes in accessibility over time. The chapter then considers the foundational concepts of accessibility measurement and representation. It also demonstrates empirical application at the project level. Moving accessibility-based evaluation from the regional scenario to the project level involves more than applying regional tools to individual decisions, because project-level analysis is inherently different from a regional analysis.

This chapter assesses the relationship between urban form and accessibility by comparing accessibility across metropolitan regions in the United States. A prevalent view among urban planning researchers is that low-density, auto-oriented metropolitan regions are also low-accessibility areas. This view, if supported, would have important implications for policy reform. For metropolitan areas in the U.S. overall, there is a positive relationship between density and auto accessibility. This suggests that land-use policy can be highly relevant to accessibility outcomes. In particular, allowing metropolitan compactness by easing land-use regulations mandating low development densities can improve the effectiveness of the roadway transportation system as defined in accessibility terms. Yet the success of the strategy remains a matter for empirical accessibility evaluation. The relationship between metropolitan density and work accessibility via automobile, while positive, is hardly ironclad, and some low-density regions do offer high auto accessibility. And transportation success overall should not just consider the automobile but should consider accessibility via all travel modes, including walking, cycling, public transport, and cars.

This chapter traces the history of the derived-demand concept, its application to the transportation context, and an important challenge to the derived view of transportation demand. The derived-demand concept, which underpins the logic of accessibility in transportation and land-use planning, originated in realms entirely removed from transportation. The derived-demand term was coined in 1895 by the economist Alfred Marshall, who used it to describe the demand curves for goods that were intermediate to the consumption or production of other goods. However, the first application of Marshall's derived-demand concept to transportation may have come four decades later in Michael Bonavia's 1936 book The Economics of Transport. The derived-demand concept in transportation was developed further by Robert Mitchell and Chester Rapkin, who were interested in forecasting demand for transportation on the basis of land-use patterns across a metropolitan area. Ultimately, the consensus view that transportation demand is mostly derived is not an absolute truth but, rather, is based on the view that transportation is most usefully viewed—in most circumstances and for most trips—as one means to an end, rather than an end in itself.

This chapter argues that because the concept of accessibility enables comparison of transportation's benefits among social groups, it is essential to proper evaluation of the social-equity impacts of transportation decisions. Unlike mobility metrics, which tend to focus on the performance of infrastructure, accessibility metrics are readily analyzed with regard to specific groups of people, such as low-income and racial-minority groups. One group that deserves special attention in equity analysis is people without access to an automobile, because the travel modes available to individuals are the single most decisive factor in determining whether they can reach destinations. However, because accessibility is inherently multidimensional and more complex than standard mobility-based metrics, several methodological considerations are essential for meaningful analysis; considering differences in mode alone is not sufficient. The influence of mode on accessibility tends to vary systematically in metropolitan space, and accessibility analysis must consider the effect of mode and location simultaneously. The chapter then explains the mobility nature of current equity evaluation, and proposes and demonstrates the use of accessibility-based equity-evaluation tools.

This chapter discusses the major themes in the evolution of accessibility over the twentieth century. The idea of accessibility is not new, either to urban and regional planning or to the social sciences in general. The concept dates back at least to Richard Hurd's 1903 analysis of urban growth, Robert Haig's 1926 “ease of contact,” and John Stewart's 1948 “demographic energy.” In Stewart's analysis, the first of the three to quantify the accessibility concept, it was a good predictor of outcomes, including observed income at the state level. Stewart also recognized the potential of accessibility as a normative goal early on: if energy or accessibility can predict important outcomes such as income, then surely it could also be seen as a policy variable to be directly manipulated by central planners. Echoing earlier authors, Walter Hansen applied the term “accessibility” to Stewart's “demographic energy” and broadly introduced the concept into the urban and regional realm with three ideas central to the planning use of the tool. First, like Hurd's and Haig's analyses early in the century—and unlike Stewart's nationally scaled research—Hansen's analysis was metropolitan, not the continental. Second, the outcome variable for Hansen was residential development, a central concern of the urban-planning profession. And finally, where Stewart had implicitly treated peoples' inclination to travel as a constant value, Hansen showed that it was a variable subject to empirical investigation.