Zhan Guo

Impact of Weather on Transit Ridership in Chicago, Illinois

This paper explores the weather–ridership relationship and its potential applications in transit operations and planning. Using the Chicago Transit Authority (CTA) in Illinois as a case study, the paper investigates the impact of five weather elements (temperature, rain, snow, wind, and fog) on daily bus and rail ridership and variation across modes, day types, and seasons. The resulting relationships are applied to the CTA ridership trend analysis, showing how preliminary findings may change after controlling for weather. The paper emphasizes the importance of having a theoretical framework encompassing weather and travel.

ASSESSMENT OF THE TRANSFER PENALTY FOR TRANSIT TRIPS: GEOGRAPHIC INFORMATION SYSTEM-BASED DISAGGREGATE MODELING APPROACH

Transit riders negatively perceive transfers because of their inconvenience, often referred to as a transfer penalty. Understanding what affects the transfer penalty can have significant implications for a transit authority and also lead to potential improvements in ridership forecasting models. A new method was developed to assess the transfer penalty on the basis of onboard survey data, a partial path choice model, and geographic information system techniques. This approach was applied to the Massachusetts Bay Transportation Authority subway system in downtown Boston. The new method improves the estimates of the transfer penalty, reduces the complexity of data processing, and improves the overall understanding of the perception of transfers.

Overweight, Obesity, and Inactivity and Urban Design in Rapidly Growing Chinese Cities

China faces rising rates of overweight, obesity, and physical inactivity among its citizens. Risk is highest in Chinas rapidly growing cities and urban populations. Current urban development practices and policies in China heighten this risk. These include policies that support decentralization in land use planning; practices of neighborhood gating; and policies and practices tied to motor vehicle travel, transit planning, and bicycle and pedestrian infrastructure. In this paper, we review cultural, political, and economic issues that influence overweight, obesity, and inactivity in China. We examine key urban planning features and policies that shape urban environments that may compromise physical activity as part of everyday life, including walking and bicycling. We review the empirical research to identify planning and design strategies that support physical activity in other high-density cities in developing and developed countries. Finally, we identify successful strategies to increase physical activity in another growing, high-density city - New York City - to suggest strategies that may have relevance for rapidly urbanizing Chinese cities.

From Minimum to Maximum: Impact of the London Parking Reform on Residential Parking Supply from 2004 to 2010?

This research examines residential parking supply in London before and after the minimum off-street parking standard was replaced by a maximum one in 2004. Based on 11 428 residential developments after and 216 developments before the reform, it is found that parking supply was reduced by approximately 40 per cent. Ninety-eight per cent was caused by the removal of the minimum standard, while only 2 per cent was due the imposition of the maximum standard. However, the parking supply is actually higher in areas with the highest density and the best transit service than in the areas immediately outside; the adopted maximum standard follows a similar pattern. The market-oriented approach to parking regulation can reduce excessive parking, but it depends on the particular sub-markets. Complementary policies such as strict parking maxima, on-street parking controls and parking taxes are often necessary to form an efficient parking market.

Residential Street Parking and Car Ownership

Problem, research strategy, and findings: Local governments’ minimum street-width standards may force developers to oversupply, and residents to pay excessively for, on-street parking in residential neighborhoods. Such oversupply is often presumed to both encourage car ownership and reduce housing affordability, although little useful evidence exists either way. This article examines the impact of street-parking supply on the car ownership of households with off-street parking in the New York City area. The off- and on-street parking supply for each household was measured through Google Street View and Bing Maps. The impact of on-street parking on car ownership levels was then estimated in an innovative multivariate model. The unique set-up of the case study ensures 1) the weak endogeneity between parking supply and car ownership and 2) the low correlation between off-street and on-street parking supply, two major methodological challenges of the study. Results show that free residential street parking increases private car ownership by nearly 9%; that is, the availability of free street parking explains 1 out of 11 cars owned by households with off-street parking. Takeaway for practice: These results offer support for community street standards that make on-street parking supply optional. They also suggest the merits of leaving the decisions of whether, and how many, on-street parking spaces to provide in new residential developments to private markets rather than regulations. Research support: This project was supported by grants from the University Transportation Research Center (Region 2) and the Wagner School Faculty Research Fund.

Modeling effects of transit system transfers on travel behavior: case of commuter rail and subway in downtown Boston, Massachusetts

Transfers can have an important influence on customer satisfaction and on whether many customers find transit service an attractive option. An empirical investigation of transfers from commuter rail to subway in downtown Boston, Massachusetts, is performed. The research identifies a higher transfer penalty between commuter rail and subway than between subway lines. Fare payment and network familiarity also are shown to affect transfer decisions. Despite a large variation of the transfer experience between the stations analyzed, riders seem to have a similar perception of transfers. For example, in most cases, the perceived transfer penalty has a narrow distribution, with a coefficient of variation below 0.5. Potential applications of the research findings to transit planning are presented.

Pedestrian environments, transit path choice, and transfer penalties : understanding land-use impacts on transit travel

This paper investigates the impact of pedestrian environments on walking behavior, and the related choice of travel path for transit riders. Activity logs from trip surveys combined with transit-route and land-use information are used to fit discrete-choice models of how riders choose among multiple paths to downtown destinations. The work illustrates (1) how the quality of pedestrian environments along transit egress paths affects transfers inside a transit system, and (2) how the impedance of transferring affects egress walking path choices. The use of GIS techniques for path-based spatial analysis is key to understanding the impact of pedestrian environments on walking behavior at the street level. The results show that desirable pedestrian environments encourage transit riders to choose paths that are ‘friendlier’, even if they involve more walking after leaving transit. Policy implications for land-use planning and transit service planning are discussed.

Are Land Use Planning and Congestion Pricing Mutually Supportive

Problem: Congestion pricing and land use planning have been proposed as two promising strategies to reduce the externalities associated with driving, including traffic congestion, air pollution, and greenhouse gas emissions. However, they are often viewed by their proponents as substitutive instead of complementary to each other. Purpose: Using data from a pilot mileage fee program run in Portland, OR, we explored whether congestion pricing and land use planning were mutually supportive in terms of vehicle miles traveled (VMT) reduction. We examined whether effective land use planning could reinforce the benefit of congestion pricing, and whether congestion pricing could strengthen the role of land use planning in encouraging travelers to reduce driving. Methods: VMT data were collected over 10 months from 130 households, which were divided into two groups: those who paid a mileage charge with rates that varied by congestion level (i.e., congestion pricing) and those who paid a mileage charge with a flat structure. Using regression models to compare the two groups, we tested the effect of congestion pricing on VMT reduction across different land use patterns, and the effect of land use on VMT reduction with and without congestion pricing. Results and conclusions: With congestion pricing, the VMT reduction is greater in traditional (dense and mixed-use) neighborhoods than in suburban (single-use, low-density) neighborhoods, probably because of the availability of travel alternatives in the former. Under the same land use pattern, land use attributes explain more variance of household VMT when congestion pricing is implemented, suggesting that this form of mileage fee could make land use planning a more effective mechanism to reduce VMT. In summary, land use planning and congestion pricing appear to be mutually supportive. Takeaway for practice: For policymakers considering mileage pricing, land use planning affects not only the economic viability but also the political feasibility of a pricing scheme. For urban planners, congestion pricing provides both opportunities and challenges to crafting land use policies that will reduce VMT. For example, a pricing zone that overlaps with dense, mixed-use and transit-accessible development, can reinforce the benefits of these development patterns and encourage greater behavioral changes. Research support: This project was supported by the Mineta Transportation Institute, where the authors are research associates.

Visually Exploring Transportation Schedules

Public transportation schedules are designed by agencies to optimize service quality under multiple constraints. However, real service usually deviates from the plan. Therefore, transportation analysts need to identify, compare and explain both eventual and systemic performance issues that must be addressed so that better timetables can be created. The purely statistical tools commonly used by analysts pose many difficulties due to the large number of attributes at tripand station-level for planned and real service. Also challenging is the need for models at multiple scales to search for patterns at different times and stations, since analysts do not know exactly where or when relevant patterns might emerge and need to compute statistical summaries for multiple attributes at different granularities. To aid in this analysis, we worked in close collaboration with a transportation expert to design TR-EX, a visual exploration tool developed to identify, inspect and compare spatio-temporal patterns for planned and real transportation service. TR-EX combines two new visual encodings inspired by Mareys Train Schedule: Trips Explorer for trip-level analysis of frequency, deviation and speed; and Stops Explorer for station-level study of delay, wait time, reliability and performance deficiencies such as bunching. To tackle overplotting and to provide a robust representation for a large numbers of trips and stops at multiple scales, the system supports variable kernel bandwidths to achieve the level of detail required by users for different tasks. We justify our design decisions based on specific analysis needs of transportation analysts. We provide anecdotal evidence of the efficacy of TR-EX through a series of case studies that explore NYC subway service, which illustrate how TR-EX can be used to confirm hypotheses and derive new insights through visual exploration.

Street Standards as Parking Policy: Rethinking the Provision of Residential Street Parking in American Suburbs

This paper examines the parking mandate in residential street standards in the United States. Based on literature review and a national survey of ninety-seven principal cities in the top fifty-two metro areas, it reveals two unjustified assumptions behind the mandate: traffic lanes must maintain continuous alignment even with limited, slow traffic; and parking demand must be satisfied with dedicated parking lanes in absence of price. The mandate is likely to force markets to oversupply parking and undersupply housing. The paper calls for removal of the parking mandate from street standards and deregulation of the residential street parking market.