Search

In July 1998 California changed its graduated driver licensing laws (GDL) for new drivers under the age of 18 to include restrictions on hours of driving, carrying teen-age passengers, and requiring more adult supervised driving practice. With fatal and injury crash data from California's Statewide Integrated Traffic Records System, this study, sponsored by Caltrans, used standard regression analysis as well as the Bai-Perron stochastic multiple structural break model to determine the effect of the law on teen-age passengers and crash rates of 16 year-old drivers. We found that in the four and one-half years following implementation of the new law, crashes caused by 16 year-old drivers decreased by 11% and the average number of teen-age passengers carried by 16 year-olds decreased by approximately 31%. The combination of these two decreases resulted in the saving of 29 lives and the prevention of 2,632 injuries.To test the specific effect of the restrictions on driving between midnight and 5 AM, regression analysis was performed on the quarterly percentage of curfew crashes for 16 year-old drivers. Quarterly data was used due to the relatively small number of curfew crashes. The percentage of curfew crashes have been in a nearly significant long term down trend since 1996. There was a small, non-significant lessening of the long-term downward trend at the time of the implementation of the new law. The new law does not appear to have had a material effect on the percentage of driving done by 16 year-olds during curfew hours. This percentage was in a downtrend prior to the law and continued after the law took effect.

The study carries out an evaluation of TMCs (traffic management centers) using three methodologies; case studies, performance based regressions and time series analysis. The study is an extension of previous work that assessed the contribution of different types of intelligent transportation investments and initiatives. However, this research sought to distinguish the separate contributions of the ITS investments from the synergies of integration under a traffic management center. Secondly, the research investigated the time dimension of benefits where we investigated if there was an 'S' curve effect in which a change in the network due to an ITS investment or the introduction of a TMC lead to benefits distributed over time. The distribution was important to evaluating ITS investments. If one measured the impact of the investment too soon, in the disequilibrium period, it would underestimate the true contribution of the investment or change in process or management strategy. We found the institutions that affect TMC operations with their designation of responsibilities, who can do what, when and where, requires change before the TMC can be an effective addition to the management of the transportation network. TMCs represent an integration of hardware and people and that process and management were most important in ensuring the TMCs had added value. Our performance related regressions used levels and changes in congestion (measured by a congestion index) and changes in VMT for autos and trucks. We found that for auto VMT ramp meters were more important than CMSs in improving the system. This was, more VMT can be obtained from the system, holding congestion constant, with ramp meters. We found that TMCs had no statistical impact on auto VMT. In the case of truck VMT, the results were just the reverse; CMSs appeared to be more important than ramp meters in improving system efficiency when efficiency was measured by extracting more truck VMT from the system, holding congestion constant. As with the auto results, TMCs were not significant in the analysis. The regression using the congestion index found ramp meters appear to be 4 times as effective as CMSs. TMCs as before were not statistically significant in affecting congestion. Overall the model did not have a lot of explanatory power in sorting out the differences in congestion among counties or what the underlying contribution is of ITS relative to investments. But it is evident that among conventional congestion relief measures maintaining infrastructure (roads) is more effective than expanding capacity. It also appears that ramp meters and CMSs, indicators of improved network management are more effective in reducing congestion than are expanding the network.

This research builds on the contributions of MOU 357, 3001 and task Order 4119 all of which focus on methodological and measurement issues in benefit cost assessments of ITS applications. The important contributions of this work are not only providing methods for calculating benefits and costs but also an empirical assessment of the set of projects that have been implemented. In all of this work, as well as most other project evaluation studies, two strong assumptions are made. First, the project is implemented successfully and second the impact of the transportation project is felt wholly within the transportation choice sets of consumers and producers. In the first of these assumptions, a project could potentially be declared unsuccessful when the technology may in fact be quite appropriate and potentially provide significant benefits, but the way it was implemented may have lessened some of the potential benefits. The study of implementation is one of understanding processes and how people integrate with new methods and technologies.

In July 1998 California changed its graduated driver licensing laws (GDL) for new drivers under the age of 18 to include restrictions on hours of driving, carrying teen-age passengers, and requiring more adult supervised driving practice. With fatal and injury crash data from California's Statewide Integrated Traffic Records System, this study, sponsored by the California State Automobile Association, used standard regression analysis as well as the Bai-Perron stochastic multiple structural break model to determine the effect of the law on teen-age passengers and crash rates of 16 year-old drivers. We found that in the three years following implementation of the new law, crashes caused by 16 year-old drivers decreased by 17% and the average number of teen-age passengers carried by 16 year-olds decreased by approximately 25%. The combination of these two decreases resulted in the saving of 25 lives and the prevention of 1,910 injuries. To test the specific effect of the restrictions on driving between midnight and 5 AM, regression analysis was performed on the quarterly percentage of curfew crashes for 16 year-old drivers. Quarterly data was used due to the relatively small number of curfew crashes. The percentage of curfew crashes have been in a nearly significant long term down trend since 1996. There was a small, non-significant lessening of the long-term downward trend at the time of the implementation of the new law. The new law does not appear to have had a material effect on the percentage of driving done by 16 year-olds during curfew hours. This percentage was in a downtrend prior to the law and continued after the law took effect.

AVL represents a radical change to many working in the public transit industry. When a new technology is introduced factor proportions change, responsibilities are altered and procedures change. There are threats to lines of authority, job security and responsibility. In all cases there are threats and the successful implementation of a new technology into any firm requires that it be managed, it will not happen automatically and ultimate success of the firm will be contingent on the implementation. The adoption of new technologies has always presented challenges for managers, employees, and organizations in general. As the advent of mass production in the assembly line and more recent models of flexible specialization required planners and workers alike to adapt to and exploit new ways of interacting and organizing the productive process, so too have advances in Information Technology (IT). The three key obstacles: employee resistance, insufficient management support, and inadequate resources explain the major part of difficulties in implementing of new technology. These new technologies offer great benefits for public and private firms, but when a new technology is implemented the organization faces a new and sometimes unexpected problem: employees resist the new technology. The consequences can be severe - experienced specialists may quit or retire because they don't want to adjust to new technologies and, the remaining staff may work more slowly and less efficiently. In this paper we will examine employee and organizational reactions to technical change in both manufacturing and information management sectors, discuss the findings of previous studies, and identify ways for organizations to deal with the employee-oriented challenges of change.

Many-to-many demand responsive transportation systems consist of vehicles which take passengers from their origins to their destinations within a service area. In dial-a-vehicle systems, in order to circumvent the undesirable feature of taxicab systems, vehicles are allowed to deviate from their direct route to serve other passengers and the emphasis is on building efficient tours to increase vehicle productivity. This strategy increases riding times but also increases average occupancy and productivity of the vehicles, and hence decreases average waiting times. A similar problem is faced by the recently developed 'webvan' food delivery service which takes orders for groceries over the internet and commits to delivery to the order's home (or specified address) within a given time frame. The difference is there is a single origin for a defined market area but multiple destinations. It is possible to organize dial-a-transit system in a similar manner but it is not clear how this form of delivery configuration would impact the productive use of the vehicles, drivers and other factors used. The interest we have in this area is to develop a model that can be used to assess the improvement in productive efficiency or of consumer welfare with the use of ITS applications, such as AVL in providing this service. AVL provides information to both the service provider and the service consumer. The information on the supplier side allows the dispatcher to allocate vehicles to achieve some objective. In most cases this has been defined to minimize costs or maximize productivity. We find this to be a narrow definition, after all this is a service industry and meeting the needs of customers should be the objective. This can be defined as maximizing consumer welfare or utility. Perhaps a more reasonable objective and one that recognizes the scarce resource issue is to have an objective of maximizing welfare which means the sum of consumer and producer surplus. Such an objective function recognizes the separate roles of customers and suppliers and the trade-off of increasing costs and increasing quality. Using this approach we should be able to say something about optimal market size, vehicles per market and optimal vehicle size. Below we develop the beginnings of an algorithm that can be used to measure the contribution of AVL to both passenger (customer) welfare and supplier efficiency. The development can be considered in four stages. In the simplest case demand is fixed spatially and market size is fixed. For a given geographic area (so many city blocks) and for a given fixed known demand that is distributed in some way around this geographic area, and for a homogenous type of demand solve for the optimal routing and scheduling according to some objective function. The objective function may be economic welfare (sum of consumer plus producer surplus), to maximize consumer welfare, to minimize costs. All are possible candidates.

Technological innovations have recently changed many of the ways the private trucking industry operates. These changes have enabled trucking firms to monitor more closely the distribution of goods and services, improve productivity, and develop higher levels of customer satisfaction. Of these innovations, ITS related applications play an important role in creating benefits for the private sector. ITS technologies are also increasingly offering the potential to bring about change to state and national agencies charged with overseeing goods movement in trucking. Recent research has shown that public agencies may be able to significantly reduce costs through the adoption of certain ITS applications. Given the facts that the private sector has been experiencing the benefits brought about by innovations in transportation and ITS, experience in the private sector may offer guidance to public agencies wishing to adopt a given ITS technology. Despite the fact that the public and private sectors often use technologies in different ways, categories of benefits may be similar, and lessons from implementation may be transferable between the two. This report gives a brief overview of the studied benefits of ITS to private firms and the experienced and expected benefits to the public sector. As specific examples of the ways in which technology has changed the way private trucking firms operate, Electronic clearance and supply chain management are looked at. Electronic clearance is an ITS application that allows trucks to use transponders to move through vehicle inspections stations and border crossing with minimal delay. Supply chain management is a concept increasingly employed by private firms to increase productivity. Though not directly associated with ITS applications, supply chain management relies largely on technology-based process monitoring to realize its benefits. Public agencies may be able to extract some valuable lessons from supply chain management in the potential to apply its principles to vehicle operations and regulatory oversight.

This project examines the expected benefits of varying combinations of ITS applications: Freeway Service Patrol, Changeable Message Signs, and Ramp Metering. The research analyzes the simulated results of a stylized network in a microscopic traffic simulator. The traffic network includes parallel roadways, ramp meters and changeable message signs.We have tested these technologies in various combinations. We measure effectiveness and define a measure of inter-technology economies.In brief, it is found that additional technologies are sub-additive, and more benefits come from each technology in isolation than when it is bundled with other technologies.

This report describes the outcome of a set of experiments undertaken to assess the net benefits of ITS applications in a stylized urban and near urban highway network.

Road transport infrastructure can, together with other factors, influence location choices and decisions involving residential, commercial, and industrial development. The network of roads and highways provides a means for access for workers and materials as well as a way for distributing products and services. Greater access lowers the costs of transportation and therefore increases the supply of many resources, including land, labor, and materials. An investment in highway infrastructure can have a variety of land use impacts, depending upon which of the above factors have been affected and how important they are. The impact also depends on the nature of the investment. For example, the effect of building a new freeway is likely to differ from that of expanding the capacity of an existing one. The impacts of enhancements to radial and circumferential routes may also differ.There is a sizable literature concerning the impact of road investments on land use, land values, development activity, social and community variables, and local and regional economies. The studies have been carried out in a number of different communities in the U.S. and have used a variety of research methods, from case studies to large-scale regional models. There is, however, a paucity of empirical work that attempts to isolate the impact of transportation investments in a statistically rigorous way. Much of the literature uses a case study approach that is highly descriptive and yields anecdotal information (1-5). Such studies are often inconclusive concerning the existence of linkages, and invariable so with regard to their magnitude. Other studies, while more quantitative, rely on complex models that are virtually impossible to validate (6-8).In this study we employ econometric techniques to study land use impacts of highway capacity expansion projects in several corridors, all located in California’s four largest urban areas. Our analysis is intended to measure the effect of the expansions upon land use in the areas served by the expanded roadway, after controlling for other factors. Section 2 overviews our research approach, while section 3 describes our data set. Section 4 presents an exploratory analysis of development impacts from road capacity expansion, based on simple graphical techniques, and argues that this indicates the need for more rigorous statistical analysis. Section 5 documents the procedure for this analysis, and Section 6 discusses its results. A summary and conclusion are offered in Section 7.

This research provides the first evidence of whether and how ITS contributes to economic growth and productivity – an objective established by the California Transportation Plan and ITS in particular. The next set of questions includes, what industries are most affected by ITS applications? Does it matter how many ITS applications are present, in other words, are there diminishing returns to similar ITS projects? Finally, does it matter how ITS projects are combined? This latter question also arose out of our research on production functions as well, and will be a central part of the subsequent research agenda.

The research reported in this document uses Total Factor Productivity (TFP) techniques, with which we develop measures of productivity performance of public transit systems of varying sizes and locations, and use this baseline to examine the potential contribution of alternative ITS applications. TFP aggregates outputs on the basis of their revenue contribution and inputs on the basis of their relative importance to total costs to calculate the overall firm productivity as a function of these quantities. The focus of this research was how the opportunities for improving efficiency via AVL are manifest in the transit operation, if at all, through the use of FTP. Overall, the results indicate a number of efficiency gains resulting from the use of AVL systems. As transit agencies across the country strive to offer the best service possible, the use of ITS and specifically AVL will be of the utmost importance. Since the number of agencies using AVL has increased greatly in the last few years, there will be excellent opportunities to revisit this topic in the years to come.

The benefits of highway improvements, or the adverse consequences of neglect, affect not only those who travel the highways, but society in general. Benefits reach the users of the roads primarily through the savings on the operating costs of their vehicles, the reduction in highway accidents, and reduction in travel time, as well as other factors that cannot be quantified as easily, such as better air quality, comfort, and convenience. Non-users can also benefit with a reduction in accidents as well as environmental degradation. From this point of view, any highway project should be considered an investment, the main objective of which is the highest social return at a given funding level. While some would debate whether road conditions in general have improved during the past few years, the federal government has distributed more highway money to states to spend on repair and reconstruction. However, the most heavily traveled freeways and principal arterials— those in metropolitan areas—are still not in good shape. According to federal statistics (provided by the states), 57 percent of urban freeways and expressways were found to be in fair to poor condition.(1) The failure to adequately maintain roads is costing drivers. Motorists pay both for road repair and for the damage caused to their cars by bad roads. Dittmar, 1998, estimated the costs of rough roads in terms of increased wear and tear, repair expenses, and decreased fuel economy, and found that poor roads cost American drivers an estimated $5.9 billion a year.(1) Rhode Island drivers pay the most, followed by California, Colorado, Maryland, and Illinois. Among metropolitan areas, drivers in the Los Angeles-Anaheim-Riverside area pay $1,325 over the life of their cars because of poor road conditions, second only to Detroit-Ann Arbor residents who pay $1,416. Motorists in the metropolitan areas of Chicago, Denver, and St. Louis follow these cities.

Recent literature has extensively discussed the social costs of highway travel.  Over the next few years, driver behavior should become more informed with the advent and deployment of in-vehicle navigation systems. Information technology will provide the driver the minimum travel time between his or her current location and final destination, updated to consider real-time recurring and non-recurring congestion. This paper considers the effects of those systems, which not only reduce the driver's travel time and vehicle operating costs, but also have positive or negative external travel time effects for other commuters and environmental effects for society at large. Furthermore, over the long term, such systems may reduce the need to construct additional highway infrastructure, or may induce additional demand.

The Santa Clara Valley Transportation Authority (VTA), which provides public transportation to citizens of Santa Clara County, California, operates buses, light rail, and paratransit service. The VTA is currently installing automatic vehicle location (AVL) equipment on its bus fleet. This report presents the results of Phase 1 research, which examines the various performance and operational characteristics of the fixed-route bus system operated by the VTA. The purpose is to identify performance characteristics of the bus system that should and could be improved with and without utilizing AVL. Characteristics examined include: schedule adherence, transfer coordination, passenger waiting time, and passenger information need.  Possible control strategies for improving performance and operational characteristics of the bus system are identified. An evaluation framework for assessing the potential  benefits/costs of alternative strategies for  improving transit performance and operational characteristics is also developed. This research was based on empirical evidence collected through field observations, interviews with the VTA's transit personnel, VTA's records, a survey of bus riders, and a literature review.

This study undertakes an evaluation of the benefits and costs of ramp metering. The primary purpose was to provide empirical information on the value of the introduction and use of this form of ITS technology. Three cases are examined in the analysis. The impact of ramp metering on traffic behavior is simulated based on a cell transmission model and an assumed travel demand on the freeway as well as the ramp. Temporal travel demand change is determined based on the average travel pattern obtained from the I-880 freeway database. Isolated, single traffic responsive ramp metering is assumed. We identify and quantify the benefits and costs based on established assumptions, and finally analyzed economic value of ramp metering. Benefits of ramp metering are derived based on travel time value and fuel consumption and by savings in travel delay. In this study, it turns out that there is a net increase in vehicle emissions as a result of with ramp metering.

The Carquinez Bridge ETC project is a pilot project of a statewide toll bridge improvement project undertaken by Caltrans. Caltrans owns and operates nine toll bridges statewide. Over the last five years, traffic on all area bridges has increased from 129 million vehicle crossings in Fiscal year (FY) 1992-93 to 140 million in FY 1996-97, with an average annual rate of 2 percent as indicated in Figure 1.  However, the toll facilities are antiquated.  The bridges use a toll collection system known as Toll Registration, Audit and Collection (TRAC) installed in the early 1980s, and tolls have been collected manually by toll collectors in tollbooths. With the significant growth in traffic volume in the bridges and deterioration of the facilities, Caltrans decided to replace the TRAC system with the ETC system on all bridges.

In this document a framework for evaluating ITS projects is developed. One of the central issues addressed is whether ITS projects are distinctly different from other more conventional transportation projects and  thus the traditional decision methods such as Benefit-cost analysis cannot be used. The answer is mixed. The decision models used in the past are still relevant, however, these have been applied in an environment in which there was a well developed data base. The models identified, selected, assembled and evaluated data to make judgements as to whether the proposed projects were good or less good public investments. With ITS there is not the history of data on either the cost or benefit (demand) side. Therefore, ITS projects are much more model oriented than data collection oriented. In effect the data or information to be used in the decision models applied to ITS project evaluation must be generated through the use of models including simulation models.

California’s Transportation Plan [CTP] was designed to set the course for the future of transportation in California.’ At the heart of the plan are three comprehensive policies; promoting the economic vitality of California by assuring mobility and access for people, goods, services and information, provide safe, convenient and reliable transportation and, provide environmental protection and energy efficiency. The Caltrans Strategic Plan in keeping with the CTP creates a vision of a balanced, integrated multimodal transportation network to move people, goods, services and information freely, safely and economically. In order to realize this vision Caltrans has invested in the Advanced Transportation Systems Program [ATS] a multimodal research and development program. This program provides a foundation for the application of advanced technologies to transportation in California. The objective of the program is to accelerate implementation of advanced transportation technology applications. A sub-component of ATS is the Intelligent Transportation Systems (ITS) which was the designation given to the multimodal package of transportation innovations but is more narrowly designating the use of advanced technologies in electronics and information to improve the performance of vehicles, highways and transit systems.

The Full Cost of Intercity Transportation Page ES-1 This study evaluates the full cost of three modes of intercity transportation: air, highway, and high speed rail. The evaluation is done within the context of the California Corridor, connecting the Los Angeles Basin and the San Francisco Bay Area. The purpose of evaluating full cost is to compare the economic implications of investment in, or expansion of, any of these three modes. The scope of the analysis is full transportation cost. Full transportation costs includes external, or social cost, in addition to the internal costs of construction, operation and maintenance. In this study we include estimates of four types of external, social costs: accidents, congestion, noise, and air pollution. The 677 kilometer corridor for which these estimates are computed represents one of the alignments of a proposed high speed rail system between Los Angeles and San Francisco. The methodology used is to construct cost functions that relate costs to levels of output, as measured by passenger-kms. or vehicle-kms. Different types of costs are estimated as permitted by available data. These include short run costs, in which the physical capacity is held fixed; and long run functions in which capacity is allowed to expand to meet higher levels of demand. Average and marginal costs are computed for highway and for air transportation. But given the absence of high speed rail systems in California only average costs are estimated. The highway and air cost models are developed from basic principles and are estimated with actual data and system design characteristics observed in the California corridor. Rail costs are estimated with models that have been adapted from estimates for the French high speed rail system, the TGV, using available data for their estimation. Based on the results summarized in Chapter 7 and shown in Table 7.1, we find that the full cost of air transportation for the California Corridor ($0.1315 per passenger-kilometer traveled (pkt)) is significantly less costly than the other two modes. The full cost of high speed rail and highway transportation cost approximately the same; rail costs $0.2350/pkt and highway costs $0.2302/pkt. The internal, or private, monetary costs comprising infrastructure, carrier, and vehicle operating costs are clearly highest for rail ($0.19/pkt), followed by air ($0.11/pkt) and then highway ($0.10/pkt). And as is to be expected, user time costs are highest for the slowest mode, the highway system, followed by rail and then air. Adding user travel time costs to the monetary costs results in the total internal system costs per passenger-km. of $0.124 for air; $0.233 for rail; and $0.198 for highway. In other words, if we disregard external costs then we find that high speed rail is nearly twice as costly as air and that the highway is not far behind. However, if we look at social costs alone -- congestion, air pollution, noise, and accidents -- we find that high speed rail is clearly less costly than the other modes. In this research the only measurable social cost of high speed rail is that of noise, which at $0.002/pkt, is significantly lower than that of air at $0.0043/pkt and highway at $0.0045/pkt. Highway transportation, on the other hand, has a relatively high cost in terms of air pollution and accidents, two externalities which are virtually absent in high speed rail. In this study, we consider that the pollution resulting from the electric power generation used to drive a train is to be allocated to the energy, and not the transportation sector. Thus, any pollution externality associated with high speed rail should be already internalized in a higher price for electricity. Similarly, a 100% safe system, such as high speed rail, implies higher capital costs due to construction of grade separations, more intelligent systems, etc... Hence, the avoidance of accidents by high speed trains is not "free". Therefore, high speed rail, while more costly than highway transportation in terms of internal costs, primarily due to its high capital cost, is significantly less costly than highway in terms of social costs. This comparison is illustrated in the following figure, where full costs are broken down into three categories: internal, travel time, and external.