Policy

Travel Demand Models in the Developing World: Correcting for Measurement Errors

Joan Walker
Li, Jieping
Srinivasan, Sumeeta
Bolduc, Denis
2010

While transport modelers in developed countries are accustomed to working with relatively rich datasets including transport networks and land use data, such databases are rarely available in developing countries. However, developing countries such as China with its immense rate of economic growth are, arguably, most in need of demand models. The research addressed in this paper is how to develop mode choice models for planning and policy analysis when level of service data are not available and resources are limited. The research makes use of a 1,001 household travel and activity survey...

Beyond Rationality in Travel Demand Models

Joan Walker
2011

The effectiveness of transportation policies will depend on how users respond to them. Therefore, we must understand how to predict and influence behavior over the long term, which is the realm of travel demand modeling. Relevant decisions made by individuals include where to live and work; the type and quantity of vehicles and transit passes to own; the types, locations and scheduling of activities; and by what modes and routes one travels to those activities. This article explores ways to improve travel demand models to reflect actual behavior, whether it is “rational” or not. The...

Concurrent Air Quality Analysis Under the National Environmental Policy Act and Transportation/Air Quality Conformity

Susan Shaheen
Guensler, Randall
Mar, Francisca
1995

This paper addresses the direct and indirect relationships between the National Environmental Policy Act (NEPA) and the new conformity requirements. This paper concludes that NEPA and transportation/air quality conformity processes should be concurrent. The need for concurrent determinations is supported by five arguments: 1) the legislative history of conformity indicates that project conformity determinations be made during the NEPA process; 2) general NEPA requirements specify coordination between environmental processes; 3) the level of technical detail required for conformity analyses...

Integrating Vehicle Design and Human Factors: Minimizing Elderly Driving Constraints

Susan Shaheen
Niemeier, Debbie
2001

With a projected rise in the number of elderly, most of whom have also relied primarily on the private automobile for their mobility, it is likely that future adaptations in vehicle design will be linked in some part to the physical infirmities often faced by the elderly. This paper offers a bridge between medical research on the physical impairments of the elderly and automobile design and driving safety. We describe recent findings on the driving-related physical and cognitive impairments faced by the elderly. We then propose two major types of vehicle design and infrastructure...

Commuter-Based Carsharing: Market Niche Potential

Susan Shaheen
2001

The automobile accounts for more than 95 percent of all person miles traveled in the United States, whereas transit accounts for less than 3 percent of all trips. Between the private automobile and traditional transit, niche markets exist for other transportation services, such as airport and transit feeder shuttles and carsharing. Commuter-based carsharing, by which individuals share a fleet of vehicles linked to transit, could potentially fill and expand one such niche; complement existing services, mainly transit and feeder shuttles; and develop into a viable transportation alternative...

California's Zero-Emission Vehicle Mandate: Linking Clean-Fuel Cars, Carsharing, and Station Car Strategies

Susan Shaheen
Wright, John
Sperling, Daniel
2002

To reduce transportation emissions and energy consumption, policymakers typically employ one of two approaches—changing technology or changing behavior. These strategies include demand management tools, such as ridesharing and vehicle control technologies—cleaner fuels and fueleconomy. Despite the benefits of a combined policy approach, these strategies are normally employed separately. Nevertheless, they have been linked occasionally, for instance in the electric station car programs of the 1990s. Station cars are vehicles used by transit riders at the start or end of a trip. In 1990, the...

U.S. Shared-Use Vehicle Survey Findings: Opportunities and Obstacles for Carsharing and Station Car Growth

Susan Shaheen
Meyn, Mollyanne
Wipyewski, Kamill
2003

Shared-use vehicle services provide members access to a vehicle fleet for use on an as needed basis, without the hassles and costs of individual auto ownership. From June 2001 to July 2002, the authors surveyed 18 U.S. shared-use vehicle organizations on a range of topics, including organizational size, partnerships, pricing, costs, and technology. While survey findings demonstrate a decline in the number of organizational starts in the last year, operational launches into new cities, membership, and fleet size continue to increase. Several growth-oriented organizations are responsible for...

Policy Considerations for Carsharing and Station Cars: Monitoring Growth, Trends, and Overall Impacts

Susan Shaheen
Schwartz, Andrew
Wipyewski, Kamill
2004

Since the late-1990s, over 25 U.S. shared-use vehicle programs—including carsharing and station cars—have been launched. Given their presumed social and environmental benefits, the majority of these programs received some governmental support—primarily in the form of startup grants and subsidized parking. As of July 2003, there were a total of 15 shared-use vehicle programs, including 11 carsharing organizations, two carsharing research pilots, and two station car programs. Over the last five years, U.S. carsharing membership has experienced exponential growth.Despite this expansion, the...

Paying for Safety: An Economic Analysis of the Effect of Compensation on Truck Driver Safety: Executive Summary

Belzer, MH
Daniel Rodriguez
Sedo, SA
2002

This report examines the link between truck driver pay and driver safety. It establishes a relationship that is important for policy purposes because it suggests that low driver pay, which we expect is linked to low but unmeasured human capital, may be an important predictor of truck driver safety. The study uses three different data sets at three different levels of analysis to demonstrate this link. The study also includes an estimation of the truck driver labor supply curve, an important contribution to understanding drivers’ (and carriers’) preferences for balancing income and work...

An Empirical Exploration of Bus Travel Times and Dwell Times in a Highly Competitive Exclusive Busway

Daniel Rodriguez
Ardila, A
2002

Busway transit has reemerged as a cost-effective transportation alternative for providing urban mobility. This article examines the operational characteristics of an exclusive busway svstem with high passenger ridership and subject to the competitive forces of individual operators. Results of a running time model suggest that the increase in running time associated with an additional passenger movement is low but that the delay imposed by recurrent vehicle deceleration and acceleration related to frequent stops is high. Frequent vehicle stops reduce fuel efficiency, increase...