Phd Dissertation

Transportation and the Environment: Essays on Technology, Infrastructure, and Policy

Abstract

With soaring oil prices and growing concerns for global warming, there is increasing interest in the environmental performance of transportation systems. This dissertation contributes to this growing literature through three independent yet related projects essays that deal with transportation technology, infrastructure, and policy.

My first essay analyzes the increasing interest for hybrid cars by Californians based on a statewide phone survey conducted in July of 2004 by the Public Policy Institute of California (PPIC) using discrete choice models. Results suggest that the possibility for single drivers to use hybrid vehicles in HOV lanes is more important than short term concerns for air pollution, support for energy efficiency policies, long term concerns for global warming, education, and income. This suggests that programs designed to improve the environmental performance of individual vehicles need to rely on tangible benefits for drivers; to make a difference, they cannot rely on environmental beliefs alone.

The second essay is concerned with assessments of Travel Demand Management (TDM) policies, which have been used to deal with congestion, air pollution, and now global warming. I compare two TDM programs: Rule 2202 (the on-road motor vehicle mitigation options in southern California) and the Commute Trip Reduction Program (CTR) in Washington State. My results show that after 2002, the impacts of Rule 2202 are mixed. Commuters’ modal choices are affected by worksite characteristics but only two (out of six) basic strategies affect the change in average vehicle ridership (AVR). Moreover, the level of subsidies appears to play an important role in commuting behavior. In Washington State, location has an impact on AVR and combinations of location and employee duties influence the single occupancy vehicle index. Details of the CTR and its relative success suggest that there is room for improving Rule 2202 by making it friendlier to businesses and more effective.

Finally, I examine the health impacts of NOx (nitrogen oxides) and PM (particulate matter) generated by trains moving freight through the Alameda Corridor to and from the Ports of Los Angeles and Long Beach. After estimating baseline emissions for 2005, I examine two scenarios: in the first one, I assume that all long-haul and switching locomotives are upgraded to Tier 2 (from Tier 1); in the second scenario, all Tier 2 locomotives operating in the study area are replaced with cleaner, Tier 3 locomotives. I find that mortality from PM exposure accounts for the largest component of health impacts, with 2005 annual costs from excess mortality in excess of $40 million. A shift to Tier 2 locomotives would save approximately half of these costs while the benefits of shifting from Tier 2 to Tier 3 locomotives would be much smaller. To my knowledge, this is the first comprehensive assessment of the health impacts of freight train transportation in a busy freight corridor.

research report

Near-Source Modeling of Transportation Emissions in Built Environments Surrounding Major Arterials

Abstract

Project included three major parts: 1) field measurements of particulate matter in five urban areas, 2) laboratory modeling of flow and dispersion within model urban areas, and 3) numerical modeling. Project website and database are located at http://emissions.engr.ucr.edu/.

working paper

Optimal Sensor Requirements

Abstract

PATH Task ORder 6328 addresses the optimal deployment of traffic detectors on freeway to ensure that adequate information is collected at the lowest possible cost. The project team produced a study framework and tools that can be applied locally to test the sensitivity of traffic data quality to detectors location and spacing, and ultimately recommend a deployment plan.

Various types of traffic detectors, including loop detectors, radars, toll tag readers and video cameras are deployed on highways. They provide the data needed to run traffic management applications such as ramp metering control, bottleneck identification, and travel times estimation. However, few studies have systematically analyzed the data requirements of these applications in terms of detector spacing and location. In other words, the trade-offs between the cost of the detectors and their benefits for traffic estimation accuracy are not well known. As a result, most highway detectors are installed using ad hoc guidelines or on a case-by-base basis, rather than through the application of measurable objectives. This in turn makes it difficult for practitioners to justify equipment and maintenance expenditures, often slowing deployment.

The product of this research is two-fold. First, we developed a framework to study the sensitivity of traffic information to sensor location and spacing and reached general conclusions. Second, the team created practical tools to assist practitioners at the local level with optimal sensor deployment. These tools include recommendations for rural areas and an Excel-based model for urban areas.

Phd Dissertation

Essays on urban economics: motorization, migration, and agglomeration

Abstract

This dissertation consists of three essays relating to urban, transportation, and labor economics, all of which focus on challenges facing large cities. While the first and second chapters examine rising car use and migration in developing countries, the third chapter examines cities in California, fragmented by their size and traffic congestion. While the first chapter is a theoretical analysis and uses numerical simulations, the second and third chapters are empirical and use microdata on households and business establishments. Chapter 1, “Motorization in developing countries,” examines the rise in car use and decline in bus use in developing countries using a theoretical, mode choice model and numerical simulations. This analysis of commuter car/bus mode choice shows that in addition to rising income, other factors may drive rising car use at the urban level including: greater income inequality, which can both increase or decrease car use; traffic congestion, which hinders buses more than cars; and policy interventions, which can reduce congestion by maintaining bus service as an alternate travel mode, even as incomes rise. Chapter 2, “Migration and the next generation,” estimates the effect of migrating to a more developed region of a developing country on the educational attainment of migrants’ children by comparing migrants, who have moved from Brazil’s Northeast region to the more developed state of Sao Paulo, to non-migrants, who remain in the Northeast. Because migration is likely to be selective, this analysis uses state level instrumental variables of distance and past migration rates to identify the effect of migration. Instrumental variables estimation finds a negative effect, suggesting that migration may make children no better off, and possibly worse off. Chapter 3, “Access to workers and employers,” attributes economies of agglomeration to either labor market pooling or employer-based productivity spillovers by estimating the effect of access to same-industry employment, other-industry employment, and specialized workers using census tract level data for four industries. The results show that both access to specialized workers and access to same-industry employers contribute to economies of agglomeration and that the magnitude of the worker effect is large relative to employer-based productivity spillovers.

Phd Dissertation

Electoral systems and regional cooperation: Politics and economics in metropolitan planning organizations

Publication Date

June 14, 2009

Author(s)

Abstract

This dissertation studies an important type of regional organizations called Metropolitan Planning Organizations (MPOs). The primary function of these organizations is the programming, funding, and construction for the bulk of surface transportation projects in the United States. Since the introduction of the Intermodal Surface Transportation Efficiency Act (ISTEA) in 1991, they are the primary conduit for billions of federal funds allocated for transportation. As a result, these largely autonomous organizations have an inordinate amount of influence on communities and the lives of the people they represent. However, due to their low salience with the public, and because their activities are wrapped up in complexity, they have largely gone unnoticed by the vast majority of the public. This dissertation models this important class of regional organization by the use of indices and parameters that are commonly used in the study of electoral systems to test the propensity of the MPOs to cooperation on a regional basis. It answers the question by first modeling the inputs, namely the electoral make up of the governing boards, and then by modeling the outputs in terms of the type of transportation projects, whether they solve a regional or a local transportation problem. This study takes a random sample of fifty MPOs and analyzes their most recent Transportation Improvement Program (TIP). These documents are published every three years and must list the funding commitments (either federal, state, or local) for each project and, in addition, they are subject to real fiscal constraints that necessitate in real tradeoffs between projects. This dissertation finds that most MPOs have historically high levels of disproportionality between seats and populations of constituting jurisdictions, and without much pressure or impetus for institutional change, this inhibits their ability to take a regional view. The high levels of disproportionality are primarily a result of a lack of regional seats and vastly varying sizes of the jurisdictions (usually cities and towns). The main finding is that the preference structures of the representatives (whether parochial or regional) predict whether projects have a local or regional focus. In summary, the MPOs ability to cooperate on a regional basis is hindered by their unbalanced governing boards which favor the one-territory one-vote notion of equality over the one-person one-vote criteria of equality.

Phd Dissertation

Essays in urban economics

Publication Date

May 31, 2009

Author(s)

Abstract

Three independent research papers, all broadly focused on urban and transportation economics comprise the chapters of this dissertation. These empirical papers address a variety of policy oriented issues surrounding the automobile. Although related in theme, the objective, scope, and empirical strategy of each paper differs. The first chapter, “Does traffic congestion reduce employment growth?”, examines the impact of traffic congestion on employment growth in large U.S. metropolitan areas. I use an historic highway plan and political variables to serve as instruments for endogenous congestion. The results show that high initial levels of congestion dampen subsequent employment growth. This finding suggests that increasing the efficiency of public infrastructure can spur local economies. A set of counterfactual estimates show that the employment-growth returns from modest capacity expansion or congestion pricing are substantial. The second chapter, “Induced demand and rebound effects in road transport” (with Kenneth Small and Kurt Van Dender) uses a simultaneous equations model and aggregate data to estimate how drivers’ respond to exogenous increases in vehicle fuel-efficiency. One consequence of efficiency improvements is an increase vehicle use, which can moderate fuel savings. Accurate measures of this so-called ‘rebound effect’, are of interest to policy makers assessing the effectiveness of the Corporate Average Fuel Economy stadards. This research paper also measures how traffic congestion and highway infrastructure affect vehicle use. The third chapter, “Evaluating the effectiveness of metered parking policy: evidence from a quasi-experiment”, uses a unique observational data set to assess metered parking policy. Although metered parking is ubiquitous, we know little about its effectiveness, particularly its impact on the retailers it is designed to assist. Sharp twice-daily changes in parking meter enforcement allow me to compare shopping behavior in both free and metered parking environments. Using the regression discontinuity design, I find that parking fees can have large impacts on nearby commerce.

Phd Dissertation

Land use regulations and housing supply impacts on local, state, and U.S. markets

Publication Date

June 14, 2009

Author(s)

Abstract

When a slumping housing market pushes a national economy towards recession, policy makers, investors and homeowners tend to focus their attention on federal regulation of housing finance. However, they have all but ignored the impacts of local and state regulations on the production of housing itself. This is surprising, since recent evidence suggests local and state land use regulations may play an important role in housing market efficiency (Mayer and Soerville, 2000; Glaser, Gyourko, and Saks, 2005). Furthermore, scholars have failed to reconcile opposing theories of land use regulations and housing supply, so consistent definitions of regulation and efficiency remain elusive. This dissertation will help reconcile the opposing theories of urban economics, political economy, and regional planning with the question: How do land use regulations effect housing markets? Do their impacts vary by scale? While these theoretical models yield radically different answers, most conclude that other regulatory approaches result in housing market inefficiencies. But with several perspectives and viewpoints, what are the fundamentals of various models? How well do models and theories portray real world markets? Which models should policy makers follow? This dissertation uses a three-paper approach to address these questions. The first paper, an integrative analysis, intimately examines the idea that land use regulations may have played a role in the emergence of the 2007 recession. Results financial deregulation and decentralization of land use in the 1980s set the stage for a large housing bubble and subsequent crash. Second, an empirical analysis examines local government regulation, competition, and housing construction in Southern California. Findings indicate that as cities permit more multifamily units, their neighbors permit less, suggesting that local regulations and intercity competition may inefficiently restrict certain housing types. The third paper analyzes the impacts of state regulation on housing growth in Maryland, and finds that it may increase multifamily housing in urban areas, but decrease in suburban and exurban areas. This suggests that cities in non-urban areas might view state regulatory incentives as a source of inefficient growth or public expenditures, and that “smart growth” programs have limited effectiveness.

Phd Dissertation

Network-wide Signal Control with Distributed Real-time Travel Data

Abstract

Advanced traffic management is a cost-effective option to reduce total delay, fuel consumption and air pollution in urban networks. Nevertheless, Adaptive Signal Control, the most advanced scheme for real-time traffic responsive operations, is still not widely used due to inadequate sensor systems and the deficiencies in the control algorithms. A novel traffic data system was recently proposed at UC Irvine named the “Persistent Traffic Cookies” (PTC) system, in which the routes traveled by the vehicles are recorded onboard and read using short-range wireless communication among vehicles and roadside devices. An advantage of this system is that there is no requirement of massive central databases and data processing of all possible vehicles in the network. The accumulated travel data is distributed across vehicles. The trip behavior inferred in the day-by-day data is used to predict individual paths and aggregated across vehicles for traffic prediction in dynamic network traffic control. This research develops traffic control schemes that use path-based data systems like PTC. Initially, methods are presented to generate the required path-based input variables such as turning flows and travel times. Two main aspects are addressed. One is a systematic approach to define spatial boundaries of subnetworks for area-control using observed traffic dynamics, the path flow between signalized intersections being used as the criterion for control dependency. The second focus is to provide network-level signal optimization, based on a decentralized control scheme yielding indirect signal coordination optimized for delay with no explicit bandwidth maximization. The local optimization uses a Dynamic Programming approach using the predicted arrival flows modeled via link traffic platoon dispersion. Optimal signal indications are found for small time steps (currently 5 seconds) within the control horizon, essentially resulting in a “cycle-less” operation. A modified rolling horizon scheme is applied, incorporating a proper calculation of the salvage cost of left-over queue after the horizon. Signal coordination is indirectly achieved and the feedback among signal decisions lead to an iterative approach. The schemes are evaluated with a microscopic simulation study of a real-world network. The results showed that the scheme reduces the total delays in the network in comparison to the Actuated Signal Control already installed in the network. It is also seen that the modified rolling horizon method with salvage cost considerations performs better than the more conventional methods.

Phd Dissertation

Dynamic Demand Input Preparation for Planning Applications

Abstract

A spectrum of traffic engineering and modern transportation planning problems requires the knowledge of the underlying trip pattern, commonly represented by dynamic Origin- Destination (OD) trip tables. In view of the fact that direct survey of trip pattern is technically problematic and economically infeasible, there have been a great number of methods proposed in the literature for updating the existing OD tables from traffic counts and/or other data sources. Unfortunately, there remain several common theoretical and practical aspects which impact the estimation accuracy and limit the use of these methods from most real-world applications. This dissertation itemizes and examines these critical issues. Then, the dissertation presents the developments, evaluations, and applications of two new frameworks intended to be used with the current and near-future data, respectively.

The first framework offers a systematic and practical procedure for preparing dynamic demand inputs for microscopic traffic simulation under planning applications with an estimation module based solely on traffic counts. Under this framework, the traditional planning model is augmented with a filter traffic simulation step, which captures important spatial-temporal characteristics of route and traffic patterns within a large surrounding network, to improve the flow estimates entering and leaving the final microscopic simulation network. A new bounded dynamic OD estimation model and a solution algorithm for solving a large problem are also proposed.

The second framework utilizes additional information from small probe samples collected over multiple days. There are two steps under this framework. The first step includes a suite of empirical and hierarchical Bayesian models used in estimating time dependent travel time distributions, destination fractions, and route fractions from probe data. These models provide multi-level posterior parameters and tend to moderate extreme estimates toward the overall mean with the magnitude depending on their precision, thus overcoming several problems due to non-uniform (over time and space) small sampling rates. The second step involves a construction of initial OD tables, an estimation of route-link fractions via a Monte Carlo simulation, and an updating procedure using a new dynamic OD estimation formulation which can also take into account the stochastic properties of the assignment matrix.