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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.
Guo, Zhan, Asha W. Agrawal & Jennifer Dill 2011. Are Land Use Planning and Congestion Pricing Mutually Supportive? Evidence From a Pilot Mileage Fee Program in
Journal of American Planning Association,
Vol. 77, 3, 232-250.
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. 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.
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. 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.
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.
Guo, Zhan 2011. Mind the Map! The Impact of Transit Maps on Path Choice in Public Transit. Transportation Research Part A: Policy and
Practice, Vol. 45, 7, 625–639.
This paper investigates the impact of schematic transit maps on passengers' travel decisions. It does two things: First, it proposes an analysis framework that defines four types of information delivered from a transit map: distortion, restoration, codification, and cognition. It then considers the potential impact of this information on three types of travel decisions: location, mode, and path choices.1 Second, it conducts an empirical analysis to explore the impact of the famous London tube map on passengers' path choice in the London Underground (LUL). Using data collected by LUL from 1998 to 2005, the paper develops a path choice model and compares the influence between the distorted tube map (map distance) and reality (travel time) on passengers' path choice behavior. Results show that the elasticity of the map distance is twice that of the travel time, which suggests that passengers often trust the tube map more than their own travel experience on deciding the ‘‘best'' travel path. This is true even for the most experienced passengers using the system. The codification of transfer connections on the tube map, either as a simple dot or as an extended link, could affect passengers' transfer decisions. The implications to transit operation and planning, such as trip assignments, overcrowding mitigation, and the deployment of Advanced Transit Information System (ATIS), are also discussed.
Guo, Zhan and Nigel H.M. Wilson 2011. Assessing the cost of transfer inconvenience in public transport
systems: A case study of the London Underground.
Transportation Research Part A: Policy and Practice, Vol.
45, 2, 91-104.
Few studies have adequately assessed the cost of transfers in public transport systems, or provided useful guidance on transfer improvements, such as where to invest (which facility), how to invest (which aspect), and how much to invest (quantitative justification of the investment). This paper proposes a new method based on path choice,3 taking into account both the operator's service supply and the customers' subjective perceptions to assess transfer cost and to identify ways to reduce it. This method evaluates different transfer components (e.g., transfer walking, waiting, and penalty) with distinct policy solutions and differentiates between transfer stations and movements.
Transfer stations are perceived very differently by passengers in terms of their overall cost and composition. The case study suggests that a better understanding of transfer behavior and improvements to the transfer experience could significantly benefit public transport systems.
This paper investigates the causal effect of pedestrian environments on walking behavior and focuses on the issue of research design. The paper differentiates between two types of research designs:treatment-based and traveler-based. The first approach emphasizes the variation of the treatment (pedestrian environments), and generally compares distinct neighborhoods, such as urban vs. suburban or transit-oriented vs. auto-dependent. The second approach emphasizes the homogeneity of subject (pedestrians), and aims at the same pedestrian under different environments normally due to home relocation, or the improvement of pedestrian environments.
This paper presents a third method, following a traveler-based research design while providing the pedestrian multiple walking paths with different pedestrian environments.
This paper investigates the impact of schematic transit maps on passengers’ travel decisions. It does two things: First, it proposes an analysis framework that defines four types of information delivered from a transit map: distortion, restoration, codification, and cognition. It then considers the potential impact of this information on three types of travel decisions: location, mode, and path choices.1 Second, it conducts an empirical analysis to explore the impact of the famous London tube map on passengers’ path choice in the London Underground (LUL). Using data collected by LUL from 1998 to 2005, the paper develops a path choice model and compares the influence between the distorted tube map (map distance) and reality (travel time) on passengers’ path choice behavior. Results show that the elasticity of the map distance is twice that of the travel time, which suggests that passengers often trust the tube map more than their own travel experience on deciding the “best” travel path. This is true even for the most experienced passengers using the system. The codification of transfer connections on the tube map, either as a simple dot or as an extended link, could affect passengers’ transfer decisions. The implications to transit operation and planning, such as trip assignments, overcrowding mitigation, and the deployment of Advanced Transit Information System (ATIS), are also discussed
Guo, Z. 2009. Does the Built Environment Affect the Utility of Walking? A Case of Path Choice in Downtown Boston.. Transportation Research D: Transport and Environment, Vol. 14, pp. 343-352 .
There is a lack of consensus as to whether the relationship between the built environment and travel is causal and, if it is, the extent of this causality. This problem is largely caused by inappropriate research designs adopted in many studies. This paper proposes a new method (based on path choice) to investigate the causal effect of the pedestrian environment on the utility of walking. Specifically, the paper examines how the pedestrian environment affects subway commuters' egress path choice from a station to their workplaces in downtown Boston. The path-based measure is sensitive enough to capture minor differences in the environment experienced by pedestrians. More importantly, path
Guo, Z. & Ning, A., Ploenske, K.R. 2008. Evaluating Environmental and Economic Benefits of Yellow-Dust Storm Related Policies in Northern China. International Journal of Sustainable Development and World Ecology, Vol. 15, pp. 457-470.
Yellow-dust storms (YDSs) have attracted increasing attention worldwide in the past decade. They can extensively disrupt socioeconomic activities and pose hazards to ecosystems, as well as human health. In recent years, China has invested multi-billions of dollars to mitigate the impact of YDSs. However, the effectiveness of such YDS-control programs has rarely been evaluated. This research develops a causal model to quantify the environmental benefits of YDS-control programs in China, and further employs regional economic models to evaluate the ensuing economic impacts. The economic benefits generated from the YDS-control programs have remained stable across the years, primarily because of the multiplier effect of the investments, while the environmental benefits tend to decline over time. Our results suggest that YDS-control programs should consider stimulating local economic activities in addition to environmental goals in order to be cost-effective and sustainable in the long term.
Guo, Z. & Ferreira Jr., J. 2008. Pedestrian Environments, Walking Path Choice, and Transfer Penalties: Understanding Land-Use Impacts on Transit Travel. Environment and Planning B: Planning and Design, Vol. 35, pp. 461-479.
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.
Guo, Z. & Wilson, N.H.M. 2007. Modeling the Effects of Transit System Transfers on Travel Behavior: A
Commuter Rail and Subway Case Study in Downtown Boston. Transportation Research Record, Vol. 2006, pp. 11-20.
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 conducted. 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.
This paper explores the weather-ridership relationship and its potential applications in transit operations and planning. Using the Chicago Transit Authority (CTA) as a case, the paper investigates the impact of five weather elements (temperature, rain, snow, wind, and fog) on daily bus and rail ridership, and its 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.
Guo, Z. & Wilson, N.H.M. 2004. Assessment of the Transfer Penalty for Transit Trips: A GIS-based
Disaggregate Modeling Approach. Transportation Research Record, Vol.1872, pp.10-18.
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 (MBTA)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.