Recent uctc_rw items

Joint mixed logit models of stated and revealed preferences for alternative-fuel vehicles

Mon, 7 Oct 2013 00:00:00 +0000

We compare multinomial logit and mixed logit models for data on California households' revealed and stated preferences for automobiles. The stated preference (SP) data elicited households' preferences among gasoline, electric, methanol, and compressed natural gas vehicles with various attributes. The mixed logit models provide improved fits over logit that are highly significant, and show large heterogeneity in respondents' preferences for alternative-fuel vehicles. The effects of including this heterogeneity are demonstrated in forecasting exercises. The alternative-fuel vehicle models presented here also highlight the advantages of merging SP and revealed preference (RP) data. RP data appear to be critical for obtaining realistic body-type choice and scaling information, but they are plagued by multicollinearity and difficulties with measuring vehicle attributes. SP data are critical for obtaining information about attributes not available in the marketplace, but pure SP...

Travel Patterns and Welfare to Work

Mon, 7 Oct 2013 00:00:00 +0000

The nation is about to enter into the second stage of welfare reform with its federal reauthorization within the upcoming year. The first stage of welfare reform started the enactment of the 1996 Personal Responsibility and Work Opportunity Act (PRWORA), which transformed welfare from an income entitlement program to transition-to-work program. As the federal and state government reauthorize welfare reform with the goal of refining existing policies and programs to enhance the ability of welfare recipients to find and hold employment, it is worthwhile to examine what we have learned about the travel patterns of welfare-to-work participants during the initial phase of welfare to work. The shift to a jobs-first approach has made transportation barriers a top priority (Blumenberg and Ong, 2001). Our recent research demonstrates that employment and earnings are tied to access to private and public transportation. Here, we examine another dimension of the nexus between welfare and...

California Housing Trends: Implications for Transportation Planning

Mon, 7 Oct 2013 00:00:00 +0000

A broad range of population forecasts and historic trends indicate that significant growth is on the horizon for California. Although population growth by geographic regions, racial/ethic groups, and age will vary, growth is a consistent trend. Naturally, growth in population implies growth in households and demand for housing units. It is imperative that any evaluation of regional growth trends to aid transportation infrastructure planning must look at housing patterns to grasp the complete picture.

Using Structural Equations Modelling to Unravel the Influence of Land Use Patterns on Travel Behavior of Urban Adult Workers of Puget Sound Region

Mon, 7 Oct 2013 00:00:00 +0000

This paper addresses the relationship between travel behavior and land use patterns using a Structural Equations Modeling framework.

The proposed model structure in this paper is by design heavily influenced by a model developed for Lisbon (1) to allow comparisons. In that paper the existence of significant effects of land use patterns in travel behavior was found. The travel behavior variables included in the model are multidimensional and comprehend both short term, number of trips by mode and trip scheduling, and long term, home location, car and pass ownership, mobility decisions. The modeled land use variables measure the levels of urban intensity and density, diversity, both in terms of types of uses and the mix between jobs and inhabitants and the public transport supply levels,. The land use patterns are described both at the residence and employment zones..

In order to explicitly account for self selection bias the land use variables are explicitly modeled...

Incentive Policies for Neighborhood Electric Vehicles

Fri, 28 Jun 2013 00:00:00 +0000

This report explores the incentives currently available for the production, sale, and use of neighborhood electric vehicles (NEVs), and suggests other incentives that could be implemented. NEV incentives are needed because the use of NEVs on a large scale would provide significant air quality benefits. NEVs produce no tailpipe emissions and could replace the vast majority of short, heavily-polluting trips. NEVs could also reduce greenhouse gas emissions, increase energy efficiency, enhance energy security, reduce the land-use demands of the automobiie system, and promote the development of more "livable" communities.

In addition to the California Air Resources Board zero-emission vehicle mandate, a variety of other federal, state, and local incentives are available to manufacturers and purchasers of NEVs. This report explores the details of these incentive programs, with a particular focus on the specific vehicle definitions used by each. These definitions are important...

A Study of the Lot-Sizing Polytope

Fri, 28 Jun 2013 00:00:00 +0000

The lot-sizing polytope is a fundamental structure contained in many practical production planning problems. Here we study this polytope and identify fact-defining inequalities that cut of all fractional extreme points of its linear programming relaxation, as well as liftings from those facets. We give a polynomial-time combinatorial separation algorithm for the inequalities when capacities are constant. We also report on an extensive computational study on solving the lot-sizing problem for instances up to 365 time periods with varying cost and capacity characteristics.

Markets and regulatory hold-up problems

Fri, 28 Jun 2013 00:00:00 +0000

Many regulatory programs such as environmental regulation are effective only if firms make irreversible investments that reduce the cost of compliance. A firm potentially subject to regulation may therefore behave strategically by not investing, thereby forcing the regulator to void the proposed regulation. We show that such incentives, which resemble a hold-up problem, may not be overcome when governmentÃ¢â�¬â�¢s only tool is the imposition of an emissions tax. The hold-up problem can be overcome by the issuance of tradeable permits. A time-consistent equilibrium exists with all firms investing and the government imposing regulations, even if no permits are traded and their market price is low. Indeed, an observation of no trade may indicate that pollution abatement is great.

Investigating travel behavior of nondriving blind and vision impaired people: The role of public transit

Fri, 28 Jun 2013 00:00:00 +0000

Our purpose is to explore the travel behavior of blind or vision impaired people, focusing in particular on travel by bus. We differentiate the sample depending on the availability of a household car. We examine perceptions of and attitudes toward existing transit and various transit characteristics, highlighting features that seem to be frustrating or difficult. Finally, we have traveler evaluate the potential usefulness of various assistive devices, including electronic information that gives navigational assistance.

A New Direction for Applied Geography

Fri, 28 Jun 2013 00:00:00 +0000

The aim of this paper is to encourage those interested in applied geographical research to broaden their horizons to consider exciting new areas where geographical expertise has much to offer. A brief overview of dominant past trends is followed by a suggestion to apply geographical knowledge and research methods to benefit disabled populations. Several possible venues for making this commitment are explored, and some interesting and useful contributions are reviewed to show that geography has as much to offer as other disciplines in searching for solutions to the probIems of the disabled. © 1997 john Wiley & Sons, Inc.

Spatial Behavior in Transportation Modeling and Planning

Fri, 28 Jun 2013 00:00:00 +0000

The demand for transportation services is a derived demand based on the needs of people to perform daily and other episodic activities. There have been two dominant approaches to investigating this derived demand: (a) studies focused on the spatial behavior of people, that is, the recorded behavior of people as they move between origins and destinations (e.g., Hanson & Schwab, 1995), and (b) an examination of the decision-making and choice processes that result in spatially manifest behaviors (e.g. Ben-Akiva & Lerman, 1985: Ortuzar & Willumsen, 1994). The former approach has been typified by the development of methods for describing and analyzing activity/travel patterns. The latter is typified both by the development of methods for describing and modeling the final outcomes of decision processes but paying little attention to the cognitive processes involved in determining the final decision concerning movement in space, and behavioral process models paying particular...

Removing functional barriers: Public transit and the blind and vision impaired

Fri, 28 Jun 2013 00:00:00 +0000

We surveyed 55 blind and vision impaired bus riders in Santa Barbara, California to analyze their use of the local bus system and identify their frustrations, concerns and desires when using a mass transit system. The most important finding was that they needed better access to INFORMATION. We asked question on what kind of technology they would like to use to better access this information. The study revealed the benefits to be gained by using auditory signage to provide information to identify busses and trains, locate and safely cross streets and find and use terminal resources. We conclude this report with an examination of the benefits of using auditory signs.

Spatial Mismatch Outside of Large Urban Areas: An Analysis of Welfare Recipients in Fresno County, California

Fri, 28 Jun 2013 00:00:00 +0000

Numerous scholars assert that welfare recipients face a mismatch between their residential location in inner-city or rural areas where they live far from employment opportunities located in the suburbs. However, the findings of this study bring into question the wholesale application of the spatial mismatch hypothesis to all welfare recipients. Welfare recipients in mid-sized cities such as Fresno, California, do not face spatial barriers to employment since they live in compact areas where distances between residential and employment locations are relatively short. In contrast, job access is important in the non-urbanized areas of Fresno County where welfare recipients how live in job-rich neighborhoods are more likely to be employed than recipients who are dispersed throughout more isolated, non-urbanized areas.

Freight Operators’ Perceptions of Congestion Problems and the Application of Advanced Technologies: Results from a 1998 Survey of 1200 Companies Operating in California

Fri, 28 Jun 2013 00:00:00 +0000

Freight transportation plays a vital role in the economy of the nation and the state of California in particular. The value of total freight shipments originating in California in 1997 is estimated $638.5 billion, 10.6 percent of all US shipments by value. This represents 706.5 million tons of fright an amount equal to 7.2 percent of the freight move nationally, measured by weight. Measured by value and weight, respectively, 67.4 and 73.7 percent of this fright moved by tuck. An additional 15.4 and 2.4 percent (by value and weight) of the freight originating in California moved over more than one mode, most likely spending part of its journey over the road. The California Trucking Association estimates that trucking employs one out of twelve workers in California.

Development of a Microscopic Activity-Based Framework for Analyzing the Potential Impacts of Transportation Control Measures on Vehicle Emissions

Fri, 28 Jun 2013 00:00:00 +0000

he 1990 Clean Air Act Amendments (CAAA) and the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) have defined a set of transportation control measures to counter the rise in vehicle emissions and energy consumption due to increased travel. The value of these TCM strategies is unknown as there are limited data available to measure the travel effects of individual TCM strategies and the models are inadequate for forecasting changes in travel behavior that result from these strategies. The work described in this paper begins to provide an operational methodology to overcome these difficulties so that the impacts of the policy mandates of both CAAA and ISTEA can be assessed. This research demonstrates the benefits in vehicle emissions reduction based on optimal scheduling and linking of the activities performed by the individuals in a household. The potential of transportation policy options to alleviate vehicle emissions is determined in a comprehensive activity-based...

Assessing the Need for Highways

Fri, 28 Jun 2013 00:00:00 +0000

Behind all debates over the adequacy of highway revenues lies the tricky issue of how much money states and the federal government ought to spend on highways. States and the federal government have historically tried to determine revenue needs with technical reports known as "needs assessments." These studies usually conclude with a dollar figure that represents the revenue required to bring all roads up to some set of maintenance and performance standards. Even though a great deal of careful technical analysis can go into needs analyses, most do not actually address the question of what total level of spending would be best. Needs assessments typically identify how much money would be required to meet certain standards or to build desired lists of projects, but generally do not address whether or not such standards or lists are optimal. Drawing on examples from California, this paper reviews the evolution of both highway needs studies and fluctuations in highway...

Rethinking the Car of the Future

Fri, 28 Jun 2013 00:00:00 +0000

On September 29, 1993, President Clinton and the chief executive officer of Ford, Chrysler, and General Motors (the "Big Three") announced the creation of what was to become known as the Partnership for a New Generation of Vehicles (PNGV). The primary goal of the partnership was to develop a vehicle that achieves up to three times the fuel economy of today’s cars--about 80 miles per gallon (mpg)--with no sacrifice in performance, size, cost, ermsslons, or safety The project would cost a billion dollars or more, split fifty-fifty between government and industry over a 10-year period. Engineers were to select the most promising technologms by 1997, create a concept prototype by 2000, and build a producnon prototype by 2004

Reforming Highway Finance:California's Policy Options

Fri, 28 Jun 2013 00:00:00 +0000

Since 1923 motor fuel taxes have been the principal instrument by which revenues are raised for the construction and maintenance of the California highway system. Fuel taxes are distinguished from most other taxes because they have been conceived of as a “user fee” rather than as a general tax. Federal and state motor fuel taxes, largely levied as charges per gallon of fuel purchased, were originally adopted as the functional equivalent of tolls. Drivers who pay a tax per gallon of motor fuel consumed are paying in rough proportion to their use of the system: those who drive more tend to pay more. In keeping with the user fee principle, the funds collected in fuel taxes traditionally have not been mixed with other government revenues in general revenue funds, but have been isolated in transportation “trust funds” to be used only for specifically designated transportation purposes.

As an instrument of taxation, motor fuel taxes have much to recommend them fiscally, politically,...

Non-normality of Data in Structural Equation Models

Fri, 28 Jun 2013 00:00:00 +0000

Using census block groups data on socio-demographics, land use, and travel behavior, we test the cutoffs suggested in the literature for trustworthy estimates and hypothesis testing statistics, and evaluate the efficacy of deleting observations as an approach to improving multivariate normality, in structural equation modeling. The results show that the measures of univariate and multivariate non-normalities will fall into the acceptable ranges for trustworthy maximum likelihood estimation after a few true outliers are deleted. We argue that pursuing a multivariate normal distribution by deleting observations should be balanced against loss of model power in the interpretation of the results.

How do cities approach policy innovation and policy learning? A study of 30 policies in Northern Europe and North America

Fri, 28 Jun 2013 00:00:00 +0000

This paper reports on a study of current practice in policy transfer, and ways in which its effectiveness can be increased. A literature review identiﬁes important factors in examining the transfer of policies. Results of interviews in eleven cities in Northern Europe and North America investigate these factors further.

The principal motivations for policy transfer were strategic need and curiosity. Local ofﬁcials and politicians dominated the process of initiating policy transfer, and local ofﬁcials were also the leading players in transferring experience.

A range of information sources are used in the search process but human interaction was the most important source of learning for two main reasons. First, there is too much information available through the Internet and the search techniques are not seen to be wholly effective in identifying the necessary information. Secondly, the information available on websites, portals and even good practice guides is not...

The Role of Lifestyle and Attitudinal Characteristics in Residential Neighborhood Choice

Fri, 28 Jun 2013 00:00:00 +0000

This paper investigates the importance of attitudinal and lifestyle variables to residential neighborhood choice for 492 residents of three San Francisco Bay Area neighborhoods. One neighborhood, North San Francisco (N=155), was classified as traditional, whereas the other two, Concord (N=165) and San Jose (N=172), were classified as suburban. Separate factor analyses identified 10 attitudinal dimensions and 11 lifestyle dimensions. Mean factor scores for the three neighborhoods differed significantly for most of the factors. For example, consistent with expectations, the mean scores on the pro-high density, pro-environment, pro-pricing, and pro-alternatives attitudinal factors were significantly higher for residents of traditional NSF than for the suburban residents. On lifestyle dimensions, NSF residents were significantly more likely to be culture-lovers, and less likely to be nest-builders and altruists, than suburbanites. These seven factors, together with three sociodemographic...

Residential Self Selection and Rail Commuting: A Nested Logit Analysis

Fri, 28 Jun 2013 00:00:00 +0000

Past studies show that those living near train stations tend to rail-commute far more often than the typical resident of rail-served cities. Some contend this is largely due to selfselection, marked by those with an affinity to transit riding consciously moving into neighborhoods that are well-served by transit. This article explores the self-selection question by constructing a nested logit model that jointly estimates the probability someone will reside near a rail stop and in turn commute by rail transit, using year-2000 travel data from the San Francisco Bay Area. A multinomial logit model is also used to predict car ownership levels. The research reveals that residential location and commute choice are jointly related decisions among station-area residents. A comparison of odds ratios among those living near and away from transit, controlling for the influences of other factors, suggests that residential self-selection accounts for approximately 40 percent of the rail-commute...

Using the Revenues from Congestion Pricing

Fri, 28 Jun 2013 00:00:00 +0000

The economic theory behind congestion pricing relies on using the revenues to help compensate highway users. But can practical methods of using revenues come close to achieving this compensation, and still have salient appeal to important political groups? This paper investigates the possibilities for designing a package of revenue uses that can achieve these twin goals. The suggested approach returns two-thirds of the revenues to travelers through travel allowances and tax reductions, and uses the rest to improve transportation throughout the area, including affected business centers. By replacing regressive sales and fuel taxes, this approach offsets the tendency of the prices alone to have a regressive distributional impact. By lowering taxes, funding new highways, improving transit, and upgrading business centers, the package provides inducements for support from several key interest groups. The potential amounts of money involved are discussed using nationwide data, and...

A Simultaneous Model of Household Activity Participation and Trip Chain Generation

Fri, 28 Jun 2013 00:00:00 +0000

A trip generation model has been developed using a time-use perspective, in which trips are generated in conjunction with out-of-home activities, and time spent traveling is another component of overall time use. The model jointly forecasts three sets of endogenous variables- (1) activity participation and (2) travel time (together making up total out-of-home time use) and (3) trip generation – as a function of household characteristics and accessibility indices. It is estimated with data from the Portland, Oregon 1994 Activity and Travel Survey. Results show that the basic model, which has ten endogenous time use and trip generation variables and thirteen exogenous variables, fits well, and all postulated relationships are upheld. Test show that the basic model, which divides activities into work and nonwork, can be extended to a three-way breakdown of subsistence, discretionary and obligatory activities. The model can also capture the effects of in-home work on trip chaining...

Commercial Fleet Demand for Alternative-Fuel Vehicles in California

Fri, 28 Jun 2013 00:00:00 +0000

Fleet demand for alternative-fuel vehicles ('AFVs' operating on fuels such as electricity, compressed natural gas, or methanol) is investigated through an analysis of a 1994 survey of 2000 fleet sites in California. This survey gathered information on site characteristics, awareness, of mandates and incentives for AFV operation, and AFV purchase intentions. The survey also contained stated preference tasks in which fleet decision makers simulated fleet-replacement purchases by indicating how they would allocate thier choices across a 'selector list' of hypothetical future vehicles. a discrete choice model was estimated to obtain preference tradeoffs for fuel types and other vehicle attributes. The overall tradeoff between vehicle range and vehicle capital cost in the sample was $80/mile of range, but with some variation by fleet sector. The availability (density) of off-site alternative fuel stations was important in fleet operators, indicating that fleets are willing to trade...

Driven to Travel: The Identification of Mobility-Inclined Market Segments

Fri, 28 Jun 2013 00:00:00 +0000

It is a truism repeated countless times in the course of a transportation professional's career - "Travel is a derived demand" - that is, derived from the demand for spatially separated activities. Belief in this truism underlies a number of transportation policies designed to reduce motorized travel (whether to reduce congestion, improve air quality, or reduce the consumption of non-renewable energy). For example, much attention has been given to land use policies designed to bring origins (residences) closer to destinations (work, shopping, entertainment). "Neo-traditional" developments, which mix diverse land uses and maintain higher densities than the typical suburban sprawl, are often suggested as a potential scheme to reduce motorized travel.

Congestion and Accessibility: What's the Relationship

Fri, 28 Jun 2013 00:00:00 +0000

This project conceptually and empirically explores the complex relationships between congestion and accessibility. While congestion alters individual access to opportunities, its effects vary significantly across people, places, and time- variations that reaming relatively understudied. This report begins by proposing a conceptual framework with three components. First, congestion can constrain mobility and thus indirectly reduce accessibility. Second, congestion is associated with agglomeration of activity and with increased accessibility. Finally, congestion in in part a phenomenon of perception and behavior, cognitively altering an individuals choice set of destinations and altering actual access to opportunities. Congestion and individual travel data for the Los Angeles region are sued to explore the localized spatial relationship between congestion and accessibility. As our multifaceted framework suggests, congestion does not have a uniform effect on accessibility, but...

New Expectations for Transportation Data

Fri, 28 Jun 2013 00:00:00 +0000

Winston Churchill once wrote an insightful analysis of architecture (1). According to Churchill, we first designed buildings to accommodate our behavior and our social and cultural patterns as we understood them. But our understanding of these things was imperfect, and different architects interpreted them differently. Moreover, buildings reflected limitations posed by their sites, by their budgets, and by the building materials used. Over time, the buildings we constructed shaped our behavior and became the determinants of new social and cultural patterns.

Trends in Exhaust Emissions from In-Use California Light-Duty Vehicles, 1994-2001

Fri, 28 Jun 2013 00:00:00 +0000

Major efforts to control motor vehicle emissions have been made in recent years, both through improved emission control technologies and through gasoline reformulation. Our assessment of the impacts of these efforts was conducted in the San Francisco Bay Area, in lanes of a highway tunnel where heavy-duty vehicles are not allowed. This study focuses on the afternoon rush hour, during which over 4000 vehicles per hour travel uphill through the tunnel. Concentrations of CO, CO2, NOx, and total and speciated non-methane organic compounds (NMOC) have been measured during summers 1994-1997, 1999, and 2001. Emission factors for CO, NMOC, and NOx decreased by factors of 2-3 over the 7-year period between 1994 and 2001, with CO and NMOC showing greater percentage reductions than NOx. From our data, fleet turnover appears to have a greater overall impact on exhaust emissions than fuel changes for most pollutants. However, emissions of benzene have been greatly affected by changes in fuel...

Cognitive Maps and Urban Travel

Fri, 28 Jun 2013 00:00:00 +0000

The authors present an examination of the relationship between cognitive maps and travel behavior in urban environments. They discuss transportation-related issues such as the cognition of transportation networks, path selection, wayfinding and navigation. They examine problems of selecting paths to destinations through the use of existing transportation networks. The authors discuss concerns relating to the role of trip purpose in path selection, looking at how different purposes spawn different path or route selection strategies. The authors conclude with a look at how cognitive maps, cognitive mapping, and travel choice modeling interact.

Attitudes of Visually Impaired Persons Toward the Use of Public Transportation

Fri, 28 Jun 2013 00:00:00 +0000

This article reports on a survey of the use of buses in Santa Barbara, California, by 55 persons who are visually impaired (including those who are blind and those who have low vision). Findings on users’ frustrations, potential use of technological aids for travel, and perceptions of and attitudes toward the characteristics of bus services are presented. In addition, differences in the responses of those to whom household cars were and were not available are analyzed, and suggestions for dealing with the participants’ major concerns are provided.

Induced Demand: An Urban Metropolitan Perspective

Fri, 28 Jun 2013 00:00:00 +0000

Most studies of induced travel demand have been carried out at a fine to medium grain of analysis- either the project, corridor, county, or metropolitan levels. The focus has been on urban settings since cities and suburbs are where the politics of road investment most dramatically get played out. The problem assigned to induce demand- like the inability to stave off traffic congestion and curb air pollution- are quintessentially urban in nature.

This paper reviews, assesses, and critiques the state-of-the-field in studying induced travel demand at metropolitan and sub-metropolitan grains of analysis. Its focus is on empirical and ex post examinations of the induced demand phenomenon as opposed to forecasts or simulation. A meta-analysis is conducted with an eye toward presenting an overall average elasticity estimate of induced demand effects based on the best, most reliable research to date.

The Planned City: Coping With Decentralization: an American Perspective

Fri, 28 Jun 2013 00:00:00 +0000

Cities have always been the loci of economic productivity and social advancement. There is nothing on the horizon that would suggest this situation will change any time soon. Telecommunications advances and economic globalization will doubtlessly alter the spatial arrangement of cities in profound ways, however the inherent advantages of agglomeration (e.g., creativity spawned by face-to-face interactions, access to specialized skills, infrastructure economics) guarantee a prominent role for cities in the global economy for years to come.

Fingerprinting traffic from static freeway sensors

Fri, 28 Jun 2013 00:00:00 +0000

In this article, the authors use field data from a 5-lane freeway in Oakland, California, to demonstrate the concept that detailed information can indeed be recovered from freeway detector data with a simple visualization tool. By using the oblique plot technique, a "moving bottleneck" can be detected and its regularities quantified. As a result of this new technique, insights can be gained into wave propagation in traffic, bottlenecks caused by freeway merges bottlenecks caused by off ramps, and transition zones at the back of freeway queues.

Child Care Availability and Usage Among Welfare Recipients

Fri, 28 Jun 2013 00:00:00 +0000

Using multivariate analysis techniques to examine results of a survey of 309 single mothers on welfare in Los Angeles County, we find that a mother’s state of welfare to work and proximity to nearby licensed care impact her usage and choice of child care for her infant of preschool aged child. Her probability of using licensed care increases with age, higher earnings and a higher number of nearby licensed care slots. Having less than a high school education, having an infant in the household, being a Latina who primarily speaks English, and being involved in job search activities decrease the likelihood of suing licensed care.

Estimating Commuters' "Value of Time" and Noisy Data: a Multiple Imputation Approach

Fri, 28 Jun 2013 00:00:00 +0000

We estimate how motorists value their time savings and characterize the degree of heterogeneity in these values by observable traits. We obtain these estimates by analyzing the choices that commuters make in a real market situation, where they are oﬀered a free-ﬂow alternative to congested travel. We do so, however, in an empirical setting where several key observations are missing. To overcome this, we apply Rubin’s Multiple Imputation Method to generate consistent estimates and valid statistical inferences. We also compare these estimates to those produced in a "single imputation" scenario to illustrate the potential hazards of single imputation methods when multiple imputation methods are warranted. Our results show the importance of properly accounting for errors in the imputation process, and they also show that value of time savings varies greatly according to motorist characteristics.

Intelligent and Environmentally-Sensible Transportation System: An Alternative Vision

Fri, 28 Jun 2013 00:00:00 +0000

A recent US DOT plan grading IVHS research correctly notes that, "Over the next 20 years, a national IVHS program could have a greater societal Impact than even the Interstate Highway System " But what will those impacts be? What could they be?The primary thrust of current IVHS initiatives to accommodate more vehicles more safely using existing roadspace The principal focus is on two sets of technotogles 1) real-time mformatmn to manage traffic flowsbetter; and 2) automated controls to pack vehtcles closer together. A variety of other applications are also beingpursued, including transit and goods movement, but are receiving much less attention and government resources.The benefits of current IVHS initiatives are coming under increasing scrutiny. It appears unlikely that deploymentof IVHS technologles, other than automated vehicle controls, will lead to major congestion reductions or road capacity expansmns (e.g, Hall, 1993; AI-Deek et al, 1989) Highway automation could provide...

Carsharing in Europe and North American: Past, Present, and Future

Fri, 28 Jun 2013 00:00:00 +0000

Most automobiles carry one person and are used for less than one hour per day. A more economically rational approach would be to use vehlcles more intenslvely. Carsharing, in which people pay a subscnption plus a per-use fee, Is one means of doing so. Carsharing may be organlzed through affinity groups, large employers, translt operators, neighborhood groups, or large carshanng businesses. While carsharing does not offer convenient access to vehicles, it does provide users with a large range of vehicles, fewer ownership responsibilities, and less cost (if vehicles are not used intensively). Societal benefits include less demand for parking space and the indirect benefits resultmg from costs being more directly tied to actual usage and vehicles being matched to trip purpose. This article reviews the experience with shared-use vehmte serxqces and explores thelr ,prospects for the future, focusing on the trend toward expanded services and use of advanced communmatlon and reservation...

A Methodology for the Disaggregate, Multidimensional Measurement of Residential Neighbourhood Type

Fri, 28 Jun 2013 00:00:00 +0000

Binary designation of a residential neighbourhood as either traditional or suburban is a distortion of reality, since a location may have some characteristics of both types and since residents in different parts of the neighbonrhood may perceive its character differently. This paper presents and applies a methodology for assessing neighbourhood type that results in a measure that is continuous rather than binary, disaggregate rather than aggregate, and potentially multidimensional. Specifically, 18 variables identified by the literature as distinguishing traditional and suburban locations are measured for 852 residents of 5 San Francisco area neighbourhoods. These data are factor-analysed to develop scales on which each individual has a person-specific score. Although we expected a single ’tradifionainess’ dimension to result, instead we found two factors: traditional and suburban. Study neighbourhoods could and did score highly on both dimensions, and considerable individual...

California's Freight Patterns

Fri, 28 Jun 2013 00:00:00 +0000

This paper presents key statistics and trends in freight transportation in the United States and California. While California is obviously a large and integral part of the national economy, there are many important differences in shipment patterns between the state and the nation as a whole. These differences are primarily a result of California's role as an economic and social trendsetter for the counry as well as its role as a "gateway" to the emerging Pacific Rim economy.

A Bridge between Travel Demand Modeling and Activity-Based Travel Analysis

Fri, 28 Jun 2013 00:00:00 +0000

The focus of this paper is on the demonstration that some rather well-known network-based formulation in operations research, that have heretofore largely gone unnoticed in activity-based travel research, offer a potentially powerful technique for advancing the general development of the activity-based modeling approach. These formulations can provide an analytical framework that unifies the complex interactions among the resource allocation decisions made by household in conducting their daily affairs outside the home, while preserving the utility-maximizing principle presumed to guide such decisions. A mathematical programming formulation is developed and used to identify the similarities and difference between traditional trip-based modeling methodologies and those pertaining to an activity-based approach. It is demonstrated that the two approaches are directly related.

A GPS-based Analysis Household Travel Behavior

Fri, 28 Jun 2013 00:00:00 +0000

While characteristics of daily travel behavior have been determined from analyses of the reconstructed household travel behavior recorded in travel diaries, such reconstructions are subject to criticisms that people lie or falsely recall information about destinations, times of travel, trip purposes, trip destination, and other critical characteristics, such as under-reporting of short trips and the number of stops in a trip chain. In 1997 the Department of Transportation carried out a one week study in Lexington, Kentucky in which the cars of 100 households were equipped with GPS and in-car computers. Every stop was logged by the GPS receiver and the purpose of the trip was recorded at that time on an in-car computer. The final report of the study gave descriptions of travel behavior but performed little analysis on the data so collected. Using a CD-ROM data record of all transactions provided by DOT, we propose to examine questions such as: To what extent were the travel behaviors...

A Test of Inter-modal Performance Measures for Transit Investment Decisions

Fri, 28 Jun 2013 00:00:00 +0000

Choices among alternative transit capital investments are often complex and politically controversial. There is renewed interest in the use of performance indicators to assist in making rational and defensible choices for the investment of public funds. To improve the evaluation of rail and bus performance and provide more useful information for transit investment decision-makers, it is important to use performance indicators that fairly and efficiently compare different transit modes. This paper proposes a set of inter-modal performance indicators in which service input, service output, and service consumption are measured by total cost, revenue capacity miles/hours, and unlinked passenger trips/miles respectively based on economic principles and evaluation objectives. The proposed improvements involve the inclusion of capital as well as operating costs in such comparisons and the recognition of the widely varying capacities of transit vehicles for seated and standing...

Forecasting new product penetration with flexible substitution patterns

Fri, 28 Jun 2013 00:00:00 +0000

We describe and apply choice models, including generalizations of logit called mixed logits, that do not exhibit the restrictive independence from irrelevant alternatives property and can approximate any substitution pattern. The models are estimated on data from a stated-preference survey that elicited customers preferences among gas, electric, methanol, and CNG vehicles with various attributes.

Exploratory Study of Spatial Variation in Car Insurance Premiums, Traffic Volume and Vehice Accidents

Fri, 28 Jun 2013 00:00:00 +0000

Traffic accidents are inevitable, albeit undesirable, outcomes of vehicular travel. They impose a heavy burden to individuals and society. The most obvious individual costs are related to bodily harm, damaged property, and lost time. Even those not involved bear a cost in terms of insurance premiums to offset the risks of driving. We rely on the private market to establish the price for coverage, with state oversight to address potential problems of market concentration, imperfect information and moral hazard. The fairness of variations in premiums hinges in part on the use of unbiased actuary rates, but this is a necessary bur not sufficient condition. Differences are questionable when based on discrimination or when externalities are present.

Ameliorating congestion by income redistribution

Fri, 28 Jun 2013 00:00:00 +0000

Consider a community with individuals who consume a private good and use a congestible facility. Without a congestion fee, use of the congestible facility will exceed the socially optimal level. We show that under some conditions this externality problem can be solved by income redistribution. Indeed, the poor can gain from a redistribution to the rich.

Changing California Lifestyles: Consequences for Mobility

Fri, 28 Jun 2013 00:00:00 +0000

Underlying changes in demographics and travel are an important set of social and personal choices that determine behavior. California's reputation as a trendsetter for the rest of the nation in terms of social developments and public policy is primarily driven by the dynamic shifts in lifestyle choices of our state's individual residents and communities. These lifestyle choices and trends are intimately linked tot eh choices we make about where we live, where we work, where we shop, and perhaps most importantly for the purposes of this investigation, how we travel. Therefore, understanding lifestyle trends and their implications for travel demand and transportation infrastructure investments is a critical element in the determination of future transportation policy in California.

New Mobility: Using Technology and Partnerships to Create More Sustainable Transportation

Fri, 28 Jun 2013 00:00:00 +0000

Land development and vehicle travel continue to outpace population growth. Efforts to manage this growth and the adverse impacts associated wlth it have been mostly ineffective. Promising technology solutmns include tetecommunicat!ons (telecommuting, electromc commerce, teleconferencing, etc.), small personal vehicles (electric bikes and neighborhood vehicles); and new "smart" transport modes (car sharing, "smart" paratransit, etc.).

These options have the potential to be environmentally and econommally supertor to today’scar-dominated system. Yet none have flourished. Why? One hypothesis is that many automobile substitutes mad complements have been rejected because they have been introduced indivldually and incrementally - not as part of a coordinated transportation system

New mobility is a fundamentally new approach to this problem, focusing on mtermodal clustering of innovative technologies with exlsting transportation options to create a coordinated transportation...

Impacts of Highway Congestion on Freight Operations: Perceptions of Trucking Industry Managers

Fri, 28 Jun 2013 00:00:00 +0000

To better understand how road congestion adversely affects trucking operations, we surveyed approximately 1200 managers of all types of trucking companies operating in California. More than 80% of these managers consider traffic congestion on freeways and surface streets to be either a "somewhat serious" or "critically serious" problem for their business. A structural equations model (SEM) is estimated on these data to determine how five aspects of the congestion problem differ across sectors of the trucking industry. The five aspects were slow average speeds, unreliable travel times, increased driver frustration and morale, higher fuel and maintenance costs, and higher costs of accidents and insurance. The model also simultaneously estimates how these five aspects combine to predict the perceived overall magnitude of the problem. Overall, congestion is perceived to be a more serious problem by managers of trucking companies engaged in intermodal operations, particularly private...

Which consumers benefit from congestion tolls?

Fri, 28 Jun 2013 00:00:00 +0000

Consider a consumer who can choose to travel on a congestible fast mode or on a congestible slow mode. Users who most value time will use the fast mode. A toll on the slow mode can induce some people who initially use that mode to switch to the fast mode. A toll on the slow mode with revenue not returned to users then necessarily reduces the welfare of all users. A toll on the fast mode may raise aggregate consumer surplus.

Transit, Employment and Women on Welfare

Fri, 28 Jun 2013 00:00:00 +0000

Inadequate transportation has emerged as a major barrier to employment for welfare recipients required to transition from public assistance to employment under welfare reform. Transportation is a particularly daunting barrier for single women without access to a household car. This study uses multivariate techniques to examine whether nearby transit access impacts the employment outcomes of this population in Los Angeles County. Results show that the level of transit service near a recipient's home makes a moderate, yet statistically significant, contribution to increasing the probability of employment and transit use for work-related trips. However, recipients who use public transit face multiple problems, including overcrowding and infrequent service.

A car-following theory for multiphase vehicular traffic flow

Fri, 28 Jun 2013 00:00:00 +0000

We present in this paper a new car-following theory that can produce both the so-called capacity drop and traffic hysteresis, two prominent features of multiphase vehicular traffic flow. This is achieved through the introduction of a single variable, driver response time, that depends on both vehicle spacing and traffic phase. By specifying different functional forms of response time, one can obtain not only brand new theories but also some of the well-known old car-following theories, which is demonstrated in this paper through both theoretical analyses and numerical simulation.

A Vehicle Use Forecasting Model Based on Revealed and Stated Vehicle Type Choice and Utilisation Data

Fri, 28 Jun 2013 00:00:00 +0000

This research describes a new model of household vehicle use behavior by type of vehicle. Forecasts of future vehicle emissions, including potential gains that might be attributed to introductions of alternative-fuel (clean-fuel) vehicles, critically depend upon the ability to forecast vehicle-miles travelled by the fuel type, body style and size, and vintage of vehicle.

Measuring the Role of Transportation in Facilitating the Welfare-to-Work Transition: Evidence from Three California Counties

Fri, 28 Jun 2013 00:00:00 +0000

Welfare-to-work transportation programs are permissed on a conceptualization of the spatial mismatch hypothesis that focuses on the physical seperation between the central city locations of welfare participants, rapidly expanding job opportunities in the suburbs, and the long commutes needed to connect them. Using data from three diverse California counties, this study examines welfare recepients' spatial access to employment. The study finds that the traditional notion of spatial mismatch is less relevant to welfare recipients, many of whom live in countries in which the urban structure deos not fit the simple model of poor, central-city neighborhoods and distant, job-rich suburbs. Many welfare recepient live in job-rich areas; others live in neighborhoods that are spatially isolated from employment. To be effective, thereofre, transportation policies must be tailored to the diverse characterisitcs of the neighborhoods in which welfare recepients live.

Incorporating Vehicular Emissions into an Efficient Mesoscopic Traffic Model: An Application to the Alameda Corridor, CA

Fri, 28 Jun 2013 00:00:00 +0000

We couple EMFAC with a dynamic mesoscopic traffic model to create an efficient tool for generating information about traffic dynamics and emissions of various pollutants (CO2, PM10, NOX, and TOG) on large scale networks. Our traffic flow model is the multi-commodity discrete kinematic wave (MCDKW) model, which is rooted in the cell transmission model but allows variable cell sizes for more efficient computations. This approach allows us to estimate traffic emissions and characteristics with a precision similar to microscopic simulation but much faster. To assess the performance of this tool, we analyze traffic and emissions on a large freeway network located between the ports of Los Angeles/Long Beach and downtown Los Angeles. Comparisons of our mesoscopic simulation results with microscopic simulations generated by TransModeler under both congested and free flow conditions show that hourly emission estimates of our mesoscopic model are within 4 to 15 percent of microscopic results...

Premium Gasoline Overbuying in the U.S.: Consumer-Based Choice Analysis

Fri, 28 Jun 2013 00:00:00 +0000

High octane gasolines, includang "premium" and midgrade, steadily gained market share in the United States during the 1980s, increasing from 12% of the total gasohne market in 1983 to 15% in 1985 and 30% in 1989. This 18% increase in market share represents an aggregate revenue transfer from U.S. consumers to industry of an additional $3 billion peryear.

It is widely believed that many drivers do not gain any benefit from using premium gasoline. We review the substanual technical evidence underlying this presumption, and then analyze a survey of vehicle owners in New York and California to determine why people purchase premium gasoline, given that many of them recewe no clear benefit.

We found that demand for premium gasohne is highly elastic, women and drivers in certain regions are more inchned to purchase premmm gasoline, income plays a minor role, and the benefits are poorly understood. Many people buy premium gasoline for rather vague reasons, not on the basis...

Product Differentiation on Roads: Constrained Congestion Pricing with Heterogeneous Users

Fri, 28 Jun 2013 00:00:00 +0000

We explore the properties of various types of public and private pricing on a congested road network, with heterogeneous users and allowing for elastic demand. Heterogeneity is represented by a continuum of values of time. The network allows us to model certain features of real-world significance: pricing restrictions on either complementary or substitute links, as well as interactions between different user groups on shared links (e.g. in city centers). We find that revenue-maximizing pricing, whether restricted or unrestricted; but this difference is mitigated by the product differentiation made possible with heterogeneous users. Product differentiation also produces some unexpected distributional effects: those hurt most by pricing may be people with moderate rather than low values of time, and first-best pricing can cause congestion levels to increase for some users compared to no pricing. Ignoring heterogeneity causes the welfare benefits of a policy close to one currently...

The Role of Repeated Interactions, Self-Enforcing Agreements and Relational [Sub]Contracting: Evidence from California Highway Procurement Auctions

Fri, 28 Jun 2013 00:00:00 +0000

We empirically examine the impact of relationships between contractors and subcontractors on firm pricing and entry decisions in the California highway procurement market using data from auctions conducted by the California Department of Transportation. Relationships in this market are valuable if they mitigate potential hold-up problems and incentives for ex post rene- gotiation due to contractual incompleteness. An important characteristic of informal contracts are that they must be self-enforcing, so that the value of relationships between ¯rms and suppliers depend on the extent of possibilities for future interaction. We construct measures of the stock of contractors' prior interactions with relevant subcontractors and ¯nd that a larger stock of relationships leads to lower bids and a greater likelihood of entry. Importantly, this relationship does not hold in periods of time and areas with little future contract volume, suggesting that the self-enforcement mechanism is crucial...

Regulatory Impediments to Neighborhood Electric Vehicles: Safety Standards and Zero-Emission Vehicle Rules

Fri, 28 Jun 2013 00:00:00 +0000

The California Air Resources Board mandated the production of zero-emission vehicles (ZEVs) starting in 1998. Other states may follow. Among the types of vehicles that may satisfy the requirements of this mandate are small, neighborhood electric vehicles (NEVs) that would be used in urban areas and on collector and arterial streets for a wide range of short trips. Although NEVs hold the potential for large energy and environmental benefits, their introduction is hindered by two institutional barriers. The first of these is the federal safety standards designed for full-sized, gasoline-powered automobiles. The second is the California ZEV regulations that may not award ZEV credits to manufacturers for all vehicles certified as ZEVs, particularly very small NEVs. Also there are important inconsistencies in the vehicle definitions used in these and other regulations and vehicle codes. This has created confusion with regard to their applicability to various small vehicle designs....

Twelve Trends for Consideration in California's Transportation Plan

Fri, 28 Jun 2013 00:00:00 +0000

This paper presents an overview of a dozen trends that have potentially significant consequences for California and its transportation plan for the next twenty years. The twelve trends discussed in the paper are:

1. A Growing Population

2. Demographic Change

3. New Patterns of Employment

4. Housing Location, Type, and Affordability

5. Change in the Central Valley

6. Changing Passenger and Household Travel Demand

7. Changing Patterns of Freight Transport

8. New Technologies

9. The Environment

10. Equity and Participation

11. Sustainable Transportation

12. The Funding Dilemma

Spatial and Transportation Mismatch in Los Angeles

Fri, 28 Jun 2013 00:00:00 +0000

One of the most salient characteristics of poor urban neighborhoods is poor labor-market outcomes. Since its conceptualization in the late 1960's, the spatial mismatch hypothesis (SMH) has been cited to explain the employment problems encountered by residents of disadvantaged urban communities. Scholars have noted an increasing geographic separation between job opportunities and low-income minorities, many of whom have remained trapped in inner-city ghettos and barrios while jobs have decentralized into the suburbs. Physical distance, then, has been recognized as an employment barrier. Spatial mismatch has also been tied to the development of underclass neighborhoods - those where at least two-fifths of the residents fall below the poverty line. These communities have experienced an exodus of the middle-class, which in turn has weakened community institutions and social networks, created a paucity of positive role models, and devastated neighborhood economies. Empirical studies...

Time Consistency of Congestion Tolls

Fri, 28 Jun 2013 00:00:00 +0000

Consider users who can choose between using two modes of travel (say a road and mass transit), and who can choose to incur a fixed cost that reduces the future cots of using mass transit. A congestion toll on the road may serve two purposes. First, it can induce users in the current period to use transit instead of the congested road. Second, users who anticipate the imposition of tolls may be induced to incur the aforementioned fixed cost, thereby reducing demand for use of the congested road in future periods. This paper focuses on such investment decisions, showing that when government cannot credibly commit to future tolls, the optimal road toll in each period may be low and congestion may be high.

Commuting Distance Sensitivity by Race and Socio-Economic Status

Fri, 28 Jun 2013 00:00:00 +0000

In this study, the authors use a specialized sample of households in the Atlanta, Georgia metropolitan area to examine the responses of individual households to the pattern of work locations in the region. The objective was to examine how race affects the probability of moving closer to a job when households change residence. Using the data set, the study shows that the commuting behaviors of relatively affluent minority and white households are consistent with the over hall hypothesis that households minimize their commuting distance whenever possible. When socioeconomic status is held constant, there are negligible differences in the responses of white and minority households. It is shown that both household types are likely to move closer to work locations with greater distances from the work location.

The Relationship Between Geographic Information Systems and Disaggregate Behavioral Travel Modeling

Fri, 28 Jun 2013 00:00:00 +0000

This paper introduces the theme of the special issue and lays a foundation for arguments concerning the potential usefulness of Object-Oriented Geographic Information Systems (OOGIS) for the development and testing of dlsaggregate behavloral travel models. It also states goals for Intelhgent Transportatxon Systems (ITS) research and discusses the role behavioral travel models m pursuing ITS goals and objectives

En-gendering Effective Planning: Spatial Mismatch, Low-Income Women, and Transportation Policy

Fri, 28 Jun 2013 00:00:00 +0000

Welfare-to-work transportation programs are predicated on a conceptualization of the spatial mismatch hypothesis that focuses on the central-city residential locations of welfare participants, rapidly expanding job opportunities in the suburbs, and the long commutes needed to connect them. Feminist scholarship and travel behavior research, however, show that the travel patterns of low-income single mothers are not consistent with this behavior, resulting in a policy mismatch between many welfare recipients and their transportation needs. The research reviewed in this article indicates that policymakers and planners should do more to address the transportation needs of these low-income women. Policies must account for the important role of gender in determining where welfare recipients will look for work, how they are likely to conduct their job searches, and the mode by which they travel to both employment and household-supporting destinations.

Driver-Shift Design for Single-Hub Transit Systems under Uncertainty

Fri, 28 Jun 2013 00:00:00 +0000

Drivers account for up to 80% of operational cost of transit agencies. This dissertation provides a method for improving the productivity of this workforce by introducing flexible contracts. Under these contracts drivers do not work the same number of hours every day. However, the number of days and hours worked every week are kept constant. These contracts allow the agency to find a better match between the number of drivers needed and hired. Since people's preference vary, intrducing this flexibility should benefit both the agency and the drivers.

Measuring the impact of efficient household travel decisions on potential travel time savings and accessibility gains

Fri, 28 Jun 2013 00:00:00 +0000

Using the conceptual framework of time-space geography, this paper incorporates both spatio-temporal constraints and household interaction effects into a meaningful measure of the potential of a household to interact with the built environment. Within this context, personal accessibility is described as a measure of the potential ability of individuals within a household not only to reach activity opportunities, but to do so with sufficient time available for participation in those activities, subject to the spatio-temporal constraints imposed by their daily obligations and transportation supply environment. The incorporation of activity-based concepts in the measurement of accessibility as a product of travel time savings not only explicitly acknowledges a temporal dimension in assessing the potential for spatial interaction but also expands the applicability of accessibility consideration to such real-world policy options as the promotion of ride-sharing and trip chaining...

Refocusing Transportation Planning for the 21st Century

Fri, 28 Jun 2013 00:00:00 +0000

As the director of a major university transportation research center, I am honored and pleased to have been included in this program in which we are exploring the contributions that research can make to the refocusing of transportation knowledge and planning practice. It is actually quite rare that line agencies or federal funding programs try to assess what research can provide and what it cannot do. But it is important to think strategically about research just as it is to think about planning and policy matters that hopefully are informed and improved by good research.

It is probably useful to conceive of the world of research as being analogous to a market like any other market for goods and services. We have suppliers who offer goods and services for sale, research studies can be thought of as a product like any other commodity of service; and those of us in universities, think tanks, and consulting firms want to sell our research services just like other purveyors...

Zen in the Art of Travel Behavior: Using Visual Ethnography to Understand the Transit Experience

Fri, 28 Jun 2013 00:00:00 +0000

Much transportation research has sought to understand the factor's influencing people's decisions to travel via one mode or another. Bodies of literature, overwhelmingly quantitative, exist about mode choice and the demographics of travel behavior. Most of this research has focused on the who, what, when and why aspects of travel. Little research has sought to explain how people travel, particularly the experiential aspects of travel. This project seeks to fill this gap in the transportation literature by examining travel behavior and decision-making using firsthand visual accounts of transit users in Los Angeles.

Inducing investments and regulating externalities by command versus taxes

Fri, 28 Jun 2013 00:00:00 +0000

A linear tax on an externality-generating activity may not attain the first-best social optimum. The problem arises because a monopolist's gain from improving the characteristics of a product may differ from social gian, even when consumers are willing to pay for change.

Why voters may prefer congested public clubs

Fri, 28 Jun 2013 00:00:00 +0000

Governmental facilities for such services as education, health, and transportation are often small, of poor quality, and overcrowded, even when the costs are spread among all taxpayers. We also find that governments may subsidize private facilities providing the same services, or may charge admission fees at public facilities. We explain these phenomena with a model which considers two types of people, rich and poor. A majority consisting of poor people may purposely build small and low quality facilities to discourage use by the rich, thereby lowering taxes. For the same reason, the poor may benefit from an admission fee at public clubs, or even from a subsidy to private clubs they do not use.

Trucking Industry Perceptions of Congestion Problems and Potential Solutions in Maritime Intermodal Operations in California

Fri, 28 Jun 2013 00:00:00 +0000

Efficient maritime transportation is heavily dependent on the smooth operation of land transportation. Swift modal transfers are key to successful intermodal operations. In this paper we examine the efficiency of maritime intermodal transfer facilities in California, from the point of view of the trucking companies that use these facilities. We also examine the perceived effects of traffic network congestion on intermodal carriers’ operations. Conclusions are based on a recent survey of nearly 1200 private and for hire carriers operating in California. Over 450 of the companies surveyed had operation involving maritime ports in California. These provided a rich sample of responses and significant insights into the current state of the industry.

Joint Models of Attitudes and Behavior in Evaluation of the San Diego I-15 Congestion Pricing Project

Fri, 28 Jun 2013 00:00:00 +0000

Understanding attitudes held by the public about the acceptability, fairness, and effectiveness of congestion pricing systems is crucial to the planning and evaluation of such systems. In this study, joint models of attitude and behavior are developed to explain how both mode choice and attitudes regarding the San Diego I-15 Congestion Pricing Project differ across the population. Results show that some personal and situational explanations of opinions and perceptions are attributable to mode choices, but other explanations are independent of behavior. With respect to linkages between attitudes and behavior, none of the models tested found any significant effects of attitude on choice; all causal links were from behavior to attitudes.

Carsharing and Partnership Management: An International Perspective

Fri, 28 Jun 2013 00:00:00 +0000

Most cars carry one person and are used for less than 1 hour per day. A more economically rational approach would be to use vehicles more intensively. Carsharing, in which a group of people pays a subscirption plus a per-use fee, is one means of doing so. Carshanng may be orgarazed through affinity groups, large employers, transit operators, neighborhoed groups, or large-aarsharing businesses Relatwe to car ownership, carsharmg has the disadvantage of less convement vehicle access but the advantages of a large range of vehacles, fewer ownership responslbihties, and less cost (if vehicles are not used intensively) The uncoupling of car ownership and use offers the potential for altenng vehicle usage and directing individuals toward other mobility options The percetved convenience (e g, preferred parking) and cost savings of carsharing have promoted a new modal splat for many carsharmg participants thioughout the world Socaetat benefits include the darect benefit of less demand...

From elevated freeways to surface boulevards: neighborhood and housing price impacts in San Francisco

Fri, 28 Jun 2013 00:00:00 +0000

Freeway “deconstruction” marks an abrupt shift in urban policy. Priorities are shifting away from designing cities to enhance mobility toward promoting economic and environmental sustainability, livability, and social equity. This paper investigates the neighborhood, traffic, and housing price impacts of replacing elevated freeways with surface boulevards in two notable yet different corridors of San Francisco: Embarcadero along the city’s eastern waterfront and Central Freeway/Octavia Boulevard serving a predominantly residential neighborhood west of downtown. A combination of informant interviews, literature reviews, and statistical analyses are used in examining neighborhood, traffic, and housing impacts of these two roadway conversions. The research shows freeway conversions generally lead to gentrification of once-declining neighborhoods, although public policies like affordable housing mandates can temper displacement effects. In general, operational and improvements to...

What Happens When Mobility-Inclined Market Segments Face Accessibility-Enhancing Policies?

Fri, 28 Jun 2013 00:00:00 +0000

lmprovements m accesstbthty are increasingly suggested as strategies leading to a reduction in vehicular travel, congeshon, pollution and their related impacts This approach assumes that individuals, if offered an opportunity, are likely to reduce their travel It also assumes that accessibility-enhancing land-use changes will increase transit and non-motorized trips in lieu of automobile usage However, there are

numerous indications that people engage in excess travei and are not necessarily inclined to reduce it. This paper presents a number of hypotheses on the reasons for excess travel and the relationships among attitudes toward travel and responses to accesslbthty-enhancmg strategies It suggests that &fferent market segments are likely to respond to pohcy measures m different ways In particular, ffa large segment of the population prefers mobility over the reduced travel offered by accesslblhty Improvements, then such pohcles will be less effective than anticipated.

Transportation Energy Use

Fri, 28 Jun 2013 00:00:00 +0000

This chapter forecasts transportation energy demand, for both the U.S. anc California, for the next 20 years. Our guiding principle has been to concentrat~ our efforts on the most important segments of the market. We therefore provide detailed projections for gasoline (58 % of California transportation energy B~in 1988), jet fueI (17%), distillate (diesel) fuel (13%), and residual bunker) fuel (10%). We ignore the remaining 2%--natural gas, aviation gasoIine, liquefied petroleum gas, lubricants, and electricity. Although we discuss prospects for the use of altematlve fuels such as methanoI and natural gas, we do not believe that these will be significant factors in the next 20 years. Table 2-1 gives an overview of transportation energy use in California and the U.S

Our forecasting methodology is based on the principle that predictions should not depend on variables that are themselves difficult to predict; for example, a forecast that uses relative fuel prices as a key...

Roadway Infrastructure for Neighborhood Electric Vehicles

Fri, 28 Jun 2013 00:00:00 +0000

The neighborhood electric vehicle (NEV) is a small, electric car designed for low-speed, local trips in neighborhoods and urban areas. The market potenttal for NEVs depends m part on the availability of a network of safe and accessible roads The processes revolved in developing new infrastructure are explored, and some design concepts are presented. To accommodate NEVs safely on existing roads designed for large vehicles and fast-moving traffic, infrastructure standards and designs will need to be modified, this will occur through a process of expertmentauon as the market for NEVs grows and plannets and engineers discover which designs work and whtch do not. The results of local experiments wdt provide the evidence for modifying state and federal rules and guidelines codified in geometric and traffic control pohcy manuals Ulumately the provision and management of roa~ infrastructure must become more flexible to accommodate alternatives to the full-stze, gasoline-powered automobile.

California Demographic Trends: Implications for Transportation Planning

Fri, 28 Jun 2013 00:00:00 +0000

Major investments in highway or transit infrastructure often require a decade or more to move from planning to completion. Therefore, a solid understanding of California's future transportation infrastructure needs implies a critical evaluation of the projections of the state's total population, what this population will look like, where they will live and work, their lifestyle choices, and most importantly, the combined impact of these factors on travel demand. Additionally, any serious evaluation of the future must consider the impact of technology, how it may change travel patterns and how it may be used as a tool for improving the effectiveness of transportation infrastructure. The following is the first in a series of working papers that will explore precisely this set of issues.

A Transaction Choice Model for Forecasting Demand for Alternative-Fuel Vehicles

Fri, 28 Jun 2013 00:00:00 +0000

The vehicle choice model developed here is one component in a mlcro-slmulatlon demand forecasting system being designed to produce annual forecasts of new and used vehicle demand by vehicle type and geographic area in Cahforma. The system will also forecast annual vehicle miles traveled for all vehicles and recharging demand by ume of day for electric vehicles. The choice model specification differs from past studies by directly modehng vehicle transactions rather than vehlcle holdings. The model Is calibrated using stated preference data from a new study of 4,747 urban Califorma households. These results are potentially useful to public transportation and energy agencles m their evaluation of alternatives to current gasoline-powered vehicles. The findings are also useful to manufacturers faced with designLug and marketing alternauve-fuel vehicles as well as to utility companies who need to develop long-run demand-side management plamung strategies

An Empirical Study of the Time Gap and its Relation to the Fundamental Diagram

Fri, 28 Jun 2013 00:00:00 +0000

The fundamental diagram is an important element in a variety of transportation studies. While various shapes of the fundamental diagram have been proposed and numerous debates on the best-fit fundamental diagram haven been made, why the fundamental diagram has many different shapes has not been well explained. This study introduces time gap as a key parameter to understand drivers’ behavioral differences at different locations and traffic conditions, then relate it to the shape of the fundamental diagram. From I-80 freeway event detector data, it is shown that time gap follows a certain probabilistic distribution and its mean value varies along locations. When downstream congestion is expected, drivers tend to take larger time gap than otherwise. It also turns out that divers take different time gaps for different travel speeds. Three different types of time gap-speed diagrams are identified and matched to Greenberg, reversed-lambda, and inverted-V types of fundamental diagrams,...

Using Sense of Place to Model Behavioral Choices

Thu, 15 Mar 2012 00:00:00 +0000

With the introduction and increasing reliance on the activity based approach in travel demand analysis and forecasting, discrete choice methods are more often in spatial contexts (e.g., residential location, job location, destination/activity choice). A necessity in specifying spatial choice models is the inclusion of the alternatives decision makers consider, and a realistic inclusion in the specification of the attributes of these alternatives, the characteristics of the decision making context, and the relevant characteristics of the decision maker. These details describe differences that exist among choices and individuals making choices. In the case of travel behavior, attributes of the alternatives have traditionally included attributes such as cost, distance, time, level of service and opportunities. Researchers however have recognized the benefit of attitudes in the estimation of choice models, showing improvement in explanatory power with the inclusion of attitudinal...

Dynamic Opportunity-Based Multipurpose Accessibility Indicators in California

Thu, 15 Mar 2012 00:00:00 +0000

Accessibility, defined as the ease (or difficulty) with which activity opportunities can be reached from a given location, can be measured using the cumulative amount of opportunities from an origin within a given amount of travel time. These indicators can be used in regional planning and modeling efforts that aim to integrate land use with travel demand and an attempt should be made to compute at the smallest geographical area. The primary objective of this paper is to illustrate the creation of realistic space-sensitive and time-sensitive fine spatial level accessibility indicators that attempt to track availability of opportunities. These indicators support the development of the Southern California Association of Governments activity-based travel demand forecasting model that aims at a second by-second and parcel-by-parcel modeling and simulation. They also provide the base information for mapping opportunities of access to fifteen different types of industries at different...

Transaction-Cost Economic Analysis of Institutional Change toward Design-Build Contracts for Public Transportation

Tue, 7 Feb 2012 00:00:00 +0000

This study uses institutional economics to shed light on many of the issues plaguing the evaluation of design-build contracting. The purpose is to assist lawmakers in the State of California as they contemplate the adoption of enabling legislation. In institutional economic terms, design-build involves the switch from public to private ordering of design services such that the design firm, which used to serve as the public client’s advocate during construction, is instead at the service of a general contractor or constructor. California is relatively rich in institutions supporting union agreements and environmental protection. In the transition to design-build dramatic changes to procedures, roles, and responsibilities ensue, which may include impacts to organized labor. Existing research suggests that design-build shortens delivery schedules by allowing construction to begin before design is complete, but the benefits of shortened schedules may come at the expense of public...

Collecting Construction Equipment Activity Data from Caltrans Project Records

Tue, 7 Feb 2012 00:00:00 +0000

Very little is known about construction equipment activity on highway projects, which is of concern because nonroad diesel construction equipment is relatively unregulated and is a major contributor to NOX and diesel PM emissions. Estimates of equipment activity are important in order to accurately model the emissions effects of road construction, and construction’s actual contribution to regional emissions inventories, as well as to better select and design appropriate mitigation strategies. To help address this gap in knowledge, construction diaries were collected for thirty recently completed Caltrans projects, sampling six typical Caltrans project types. Equipment activity for every project in the sample is categorized with an equipment category, a project phase category and a percent of project completion category. The equipment categories are primarily the NONROAD construction equipment classes, and the phase categories are aligned with the phases in the UCD Emissions...

An Empirical and Theoretical Study of Freeway Weave Bottlenecks

Tue, 7 Feb 2012 00:00:00 +0000

Though there have been numerous studies of freeway weaving sections (i.e., segments in which an on-ramp is followed by an off-ramp), there remains a significant lack of empirical and theoretical understanding of the traffic behavior that causes weaving sections to become bottlenecks with varying discharge flows. The present research entails empirical analysis and theoretical modeling of what triggered the bottleneck activations and discharge flow changes in two freeway weaving sections. Both sites were recurrent bottlenecks during the rush, and investigations revealed that changes in the spatial patterns of vehicular lane-changes, especially among Freeway-to-Ramp (F-R) maneuvers, caused variations in bottleneck discharge flow. When the F-R maneuvers were concentrated near a weaving section’s on-ramp, they became more disruptive, resulting in bottleneck activations with diminished discharge flows. Findings further indicated that the spatial distributions of these lane changes,...

Which Reduces Vehicle Travel More: Jobs-Housing Balauce or Retail-Housing Mixing?

Tue, 7 Feb 2012 00:00:00 +0000

Which land-use strategy yields greater reductions in vehicular travel: improving the proximity of jobs to housing or bringing retail and consumer services closer ro residential areas? We probe this question by examining the degree to which job accessibility is associated with reduced work travel and how closely retail and service accessibility is correlated with miles and hours logged getting to shopping destinations. Based on data from the San Francisco Bay Area, we find that jobs-housing balance reduces travel more, by a substantial margin. The article concludes by discussing policy measures that have been introduced in California to bring housing, workplaces, and retail centers closer together.

Alternative Approaches to Modeling the Travel-Demand Impacts of Smart Growth

Tue, 7 Feb 2012 00:00:00 +0000

Four-step travel demand forecasting models were never meant to estimate the travel impacts of neighborhood-level smart growth initiatives like transit villages, but rather to guide regional highway and transit investments. While progress has been made in enhancing large-scale models, some analysts have turned to post-processing and direct models to reduce modeling time and cost, and to better capture the travel impacts of neighborhood-scale land use strategies. This paper presents examples of direct or off-line modeling of rail and transit-oriented land use proposals for great Charlotte, the San Francisco Bay Area exurbs, and south St. Louis County. These alternative approaches provided a useful platform for scenario testing, and their results revealed that concentrating development near rail stations produced an appreciable ridership bonus. These alternative models are appropriate as sketch-planning supplements to, not substitutes for, traditional four-step models.

LARGE REAL ESTATE DEVELOPMENTS, SPATIAL UNCERTAINTY, AND INTEGRATED LAND USE AND TRANSPORTATION MODELING

Tue, 7 Feb 2012 00:00:00 +0000

In the past ten years, integrated land use and transportation modeling has received considerable attention in the scholarly literature. This academic interest is slowly yielding practical applications. Many metropolitan planning organizations (MPOs) and state departments of transportation are beginning to implement these types of models for the first time. While many improvements have been made to these models, and the value of these improvements should not be understated, much work still remains. One of the most challenging problems in land use modeling is how floorspace (buildings) is built and occupied. The purpose of this paper is twofold: first, to draw attention to insufficiencies in the representation of floorspace developer behavior—particularly as it applies to large, urban-edge projects—within current integrated land use and transportation models and, second, to determine the necessity of explicitly accounting for such projects within these models. The Sacramento...

Walkability Planning in Jakarta

Thu, 15 Dec 2011 00:00:00 +0000

Walking is the main mode of transportation for many of the world’s people, particularly those in cities of the majority world. In the metropolitan region of Jakarta, walking in the public realm constitutes the main transportation mode for almost 40 percent of trips—a massive contribution to urban mobility. On the other hand, there is no comprehensive planning for pedestrians in an analogous manner to other modes of transportation. Pedestrian facilities are often dilapidated, damaged, dangerous, or missing completely. Additionally, there is no process for assessing the inventory of pedestrian facilities, planning pedestrian facilities at a region-wide level, or even identifying the location of vernacular pedestrian routes in low-income and informal areas. Provincial pedestrian planning focuses on piecemeal, symbolic spaces such as monumental plazas that serve the nation-building project, but overlooks the functional network of routes that address the daily needs of the city’s...

Collaboration Is Not Enough: Virtuous Cycles of Reform in Transportation Policy

Thu, 13 Oct 2011 00:00:00 +0000

Over the past two decades, a burgeoning literature has touted the promise of regional collaboration to address a wide range of issues. This article challenges the premise that horizontal collaboration alone can empower regional decision-making venues. By analyzing efforts to create regional venues for transportation policy making in Chicago and Los Angeles, the authors show that vertical power is essential to building regional capacities. Only by exercising power at multiple levels of the political system can local reformers launch a virtuous cycle of reform that begins to build enduring regional capacities.

Understanding Places Using a Mixed Method Approach

Thu, 13 Oct 2011 00:00:00 +0000

With the increased application of the activity based approach comes the inherent need to incorporate more detail regarding behavior. This need for detail has in turn created a need for both a deeper understanding and theoretical basis for behavior, and the incorporation of data collection and analysis methods to handle more behavioral detail. Because of this, the use of qualitative and mixed method approaches in travel behavior has received increased attention over the last few decades. In this paper, quantitative and qualitative methodologies are discussed and applied to data collected in Santa Barbara, California, measuring peoples’ attitudes about places (sense of place). Both quantitative and qualitative methods are applied using first a factor analysis and complementing this with a qualitative analysis of text from an open-ended question. The findings of these analyses are compared and incorporated to contribute to a greater understanding of both sense of place and behavior....

The Quantified Traveler: Using personal travel data to promote sustainable transport behavior

Thu, 13 Oct 2011 00:00:00 +0000

With the advent of ubiquitous mobile sensing and self-tracking groups, travel demand researchers have a unique opportunity to combine these two developments to improve the state of the art of travel diary collection. While the use of mobile phones and the inference of travel diaries from GPS and sensor data allows for lower-cost, longer surveys, we show how the self-tracking movement can be leveraged to interest people in participating over a longer period of time. By compiling personalized feedback and statistics on participants’ travel habits during the survey, we can provide the participants with direct value in exchange for their data collection effort. Moreover, the feedback can be used to provide statistics that influence people’s awareness of the footprint of their transportation choices and their attitudes, with the goal of moving them toward more sustainable transportation behavior.

We describe an experiment that we conducted with a small sample in which this...

The Half-Mile Circle: Does It Represent Transit Station Catchments?

Thu, 13 Oct 2011 00:00:00 +0000

One-half mile has become the accepted distance for gauging a transit station’s catchment area in the U.S. It is the de facto standard for planning TODs (transit oriented developments) in America. Planners and researchers use transit catchment areas not only to make predictions about transit ridership and the land use and socioeconomic impacts of transit, but also to prescribe regulations, such as the relaxation of restrictive zoning, or carve out TOD financial plans. This radius is loosely based on the distance that people are willing to walk to transit, but this same reasoning has been used to justify other transit catchment areas. Using station-level variables from 1,449 high-capacity American transit stations in 21 cities, we aim to identify whether there is clear benchmark between distance and ridership that provides a norm for station-area planning and prediction. For the purposes of predicting station-level transit ridership, we find that different catchment areas have...

Regional versus Local Accessibility: Variations in Suburban Form and the Effects on Non-Work Travel

Fri, 23 Sep 2011 00:00:00 +0000

This dissertation addresses the question of how particular forms of metropolitan development affect travel patterns, a question long of concern to planners but recently the subject of a heated debate. Critics identify sprawling, low-density, single-use, automobile-dependent suburban development as the problem, and recommend a return to the higher-density, mixed-use, pedestrian-oriented design practices of the past as the solution, particularly as a way of reducing non-work automobile travel. Yet the question remains: can these “neo-traditional” communities reduce automobile travel when implemented within the broader context of freeways and regional shopping malls.

The concept of accessibility provides an important tool for resolving this question. Accessibility measures the attractiveness of potential destinations and the cost of reaching them. By measuring both the accessibility to activity within the community, or “local” accessibility, and the accessibility to regional...

GPS-Based Tracking of Daily Activities

Sun, 21 Aug 2011 00:00:00 +0000

While characteristics of daily travel behavior have been determined from analyses of the reconstructed household travel behavior recorded in travel diaries, such reconstructions are subject to criticisms. Respondents in a survey may lie or falsely recall information about destinations, times of travel, trip purpose, trip destination and other critical characteristics, such as under-reporting of short trips and the number of stops in a trip chain (Brog, et al., 1982; Purvis, 1990). In 1997 the Department of Transportation carried out a one-week study in Lexington, Kentucky in which the cars of 100 households were equipped with GPS and in-car computers. Every stop was logged by the GPS receiver, and the purpose of the stop was recorded in real time on an in-car computer. The final report of the study gave descriptions of travel behavior but performed little analysis on the data so collected. Although the new GPS-involved data collection methodology is not expected to replace...

Transportation Technologies: Implications for Planning

Sun, 21 Aug 2011 00:00:00 +0000

Transportation is rapidly being changed by new technologies, such as Intelligent Transportation Systems (including smart cards, on-board diagnostics and information systems, and smarter highways, transit, automobiles, logistics systems, and other information systems). The range of options and their impacts will continue to expand as new technologies are introduced over the next two decades, and may alter transportation systems in many ways. For example, electric, hydrogen, or hybrid electric-petroleum vehicles may be introduced that would substantially alter emissions and fuel characteristics of the fleet, and potentially pose challenges in terms of system operations and finance. Smart card technologies could greatly improve the feasibility and convenience of a variety of pricing options for road use, parking, and transit fares. Monitoring and information systems could enable travelers to time trips and select routes to avoid congestion, reducing it in the process. Advanced...

Unlimited Access

Sun, 21 Aug 2011 00:00:00 +0000

Universities and public transit agencies have together invented an arrangement – called Unlimited Access – that provides fare-free transit service for over 825,000 people. The university typically pays the transit agency an annual lump sum based o expected student ridership, and students simply show their university identification to board the bus. This paper reports the results of a survey of Unlimited Access programs at 35 universities. University officials report that Unlimited Access reduces parking demand, increases students’ access to the campus, help to recruit and retain students, and reduces the cost of attending college. Transit agencies report that Unlimited Access increases ridership, fills empty seats, improves transit service, and reduces the operating cost per rider. Increases in student transit ridership ranged from 71 percent to 200 percent during he first year of Unlimited Access, and growth in subsequent years ranged from 2 percent to 10 percent per year....

Car Ownership and Welfare-to-Work

Sun, 21 Aug 2011 00:00:00 +0000

This study examines the role of car ownership in facilitating employment among recipients under the current welfare-to-work law. Because of a potential problem with simultaneity, the analysis uses an instrumental variable constructed from insurance premiums and population density for car ownership. The data comes from a 1999-2000 survey of TANF recipients in the Los Angeles metropolitan area. The empirical results show a significant independent contribution of car ownership on employment. The presence of an observed ownership is associated with 12 percentage point increase in the odds of being employed. Moreover, the results indicate that lowering insurance premiums by $100 can increase the odds of employment by 4 percentage points.

Overview and Summary: Twelve Trends for Consideration in California's Transportation Plan

Sun, 21 Aug 2011 00:00:00 +0000

The paper concludes with a brief discussion of the implications of these trends for transportation planning. More extensive discussions of the first nine trends and the issues they raise can be found in the detailed papers that follow this summary. The last three topics are not addressed in later papers here; separate studies are being conducted on these topics.

This paper and the papers it summarizes are intended to provide a review of key literature as well as background information and data on the topics covered. We clearly do not attempt to cover every possible trend that could affect the pace or location of growth and change in California – we do not discuss, for example, the possible effects of recession, competing demands for water, or whether the current problems with the state’s electric power supply will be lasting. Nor are the papers designed to offer policy advice, although we do sometimes suggest interpretations of the data that have policy significance....

Addressing Environmental Challenges in the California Transportation Plan

Sun, 21 Aug 2011 00:00:00 +0000

The purpose of this paper is to highlight challenges the State will face as it attempts to address environmental impacts within the forthcoming transportation plan. The first section highlights major issues that shape the policy context for environmental planning. The second section summarizes key trends among major environmental categories. Finally, the implications of California’s environmental trends for the State transportation plan will be discussed.