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In this paper we evaluate and compare long-run economic effects of six road-pricing schemes aimed at internalizing social costs of transportation. In order to conduct this analysis, we employ a spatially disaggregated general equilibrium model of a regional economy that incorporates decisions of residents, firms, and developers, integrated with a spatially-disaggregated strategic transportation planning model that features mode, time period, and route choice. The model is calibrated to the greater Washington, DC metropolitan area. We compare two social cost functions - one restricted to congestion alone and another that accounts for other external effects of transportation. We find that when the ultimate policy goal is a reduction in the complete set of motor vehicle externalities, cordon-like policies and variable-toll policies lose some attractiveness compared to policies based primarily on mileage. We also find that full social cost pricing requires very high toll levels and therefore is bound to be controversial.

The document describes the Washington START transportation simulation model. In particular, it provides information about the model structure, the equilibrium concept, and the data used to calibrate the model. It also briefly describes the reference scenario and the elasticity analysis. Finally, the document discusses past and potential future applications and possible directions for model extensions.

We evaluate and compare the long-term economic effects of three cordon-based road pricing schemes applied to the Washington, DC, metropolitan area. To conduct this analysis, we employ a spatially disaggregated general equilibrium model of a regional economy that incorporates the decisions of residents, firms, and developers, integrated with a spatially disaggregated strategic transportation planning model that features mode, time period, and route choice. We find that all cordon pricing schemes increase welfare of the residents, as well as lead to GDP growth. At the optimum, the larger cordon and a double cordon lead to higher benefits than the small cordon encompassing downtown core. Nevertheless, the small cordon seems to be a safer bet because when the toll charge is set suboptimally, the net benefits from the small cordon compared to the optimum change negligibly, while the net benefits from the larger cordon decline sharply as the charge deviates from the optimal level.

We analyze a 2002 survey of Southern California residents to evaluate the relative importance of factors that affect workers’ propensity to telecommute and telecommuting frequency. The survey collected a wealth of individual demographic information as well as job type, industry, and employer characteristics from about 5,000 residents. In agreement with previous studies, we find that the propensity to telecommute is increasing with worker age and educational attainment. At the same time, we conclude that the propensity to telecommute depends to a large extent on a worker’s job characteristics and that the quantitative effects of job characteristics are at least as important as demographic factors. We also study what factors affect telecommuting frequency based on a one-week commuting diary of the telecommuters in the survey. The industry and occupation categories that play a significant role in affecting propensity to telecommute do not have similar effects on telecommuting frequency. On the contrary, some other job-related factors show substantial influences.

We employ a spatially disaggregated general equilibrium model of a regional economy that incorporates decisions of residents, firms, and developers integrated with a spatially disaggregated strategic transportation planning (START) model that features mode, time period, and route choice to evaluate economic effects of congestion pricing. First, we evaluate the long-run effects of a road-pricing policy based on the integrated model of land use, strategic transport, and regional economy (LUSTRE) and compare them with the short-term effects obtained from the START model alone. We then look at distributional effects of the policy in question and point out differences and similarities in the short run versus the long run. Finally, we analyze the mechanisms at the source of the economic and land-use effects induced by the road-pricing policy.

The discrepancy between transit’s large share of local transportation resources and its generally low share of local trips has raised questions about the use of scarce transportation funds for this purpose. We use a regional transport model consistent with utility theory and calibrated for the Washington, D.C., metropolitan area to estimate the travel benefits of the local transit system to transit users and the congestion-reduction benefits to motorists. We find that (i) rail transit generates congestion-reduction benefits that exceed rail subsidies; (ii) the combined benefits of rail and bus transit easily exceed local transit subsidies generally; (iii) the lowest-income group receives a disproportionately low share of the transit benefits, both in absolute terms and as a share of total income; and (iv) for practical purposes, the scale of the current transit system is about optimal.

In this paper, we review 20 relatively recent empirical studies of telecommuting, all of which focus on the trip reduction perspective. The studies include earlier ones with smaller datasets, such as some pilot studies of individual employers, and more recent studies based on broader surveys of both telecommuters and nontelecommuters. We focus on the results of the studies with respect to participation and frequency of telecommuting, the effects on vehicle-miles-traveled (VMT) and trips, and in some cases, the impacts on emissions and air quality. Although there does not seem to be a consensus, there is a predominant view that certain factors increase both the likelihood of telecommuting and the frequency of telecommuting. These factors are having children in the household, being female, having more education, having a longer commute trip, having worked longer for one’s current employer and/or in one’s current position, and having a job that does not require face-to-face contact with coworkers or clients. Most studies of VMT and trip reductions from telecommuting show that telecommuters significantly reduce both daily trips and VMT. Not only does commute VMT fall, but noncommute VMT appears to fall in some cases as well. The studies of VMT, however, tend to focus on the reductions for individual employees who choose to telecommute. Although an individual telecommuter may experience a sharp reduction in VMT, total benefits depend on how many people are telecommuting, how often they are doing so, and the duration of telecommuting. More research is needed with larger and more broadly based datasets across employers that include both individual employee characteristics and employer and job characteristics. This would allow a better analysis of telecommuting choice and frequency as well as more reliable estimates of VMT and emissions impacts. This discussion paper is one in a series of four RFF papers on telecommuting published in December 2004. Discussion papers 04-42 and 04-43 present analyses of two recent datasets on telecommuters. In 04-42, Nelson and Walls analyze data from five pilot cities enrolled in the "ecommute" program. In 04-43, Safirova and Walls analyze data from a broad survey conducted by the Southern California Association of Governments (SCAG) of telecommuters and nontelecommuters. Finally, in 04-45 Nelson presents an assessment of institutional and regulatory barriers to using telecommuting in a mobile source emissions trading program. The studies by RFF are part of a larger report on the ecommute program completed by the Global Environment and Technology Foundation (GETF) for the U.S. Environmental Protection Agency. More information about the overall project can be found on the ecommute/GETF website: http://www.ecommute.net/program/.

In this paper, we analyze the 2002 Telework Survey conducted by the Southern California Association of Governments (SCAG). Being a relatively recent and large dataset, the survey captures the current state of telecommuting, covering the entire region with a population of 17 million residents, and is not biased by telecommuting policies of particular employees. The survey also distinguishes telecommuters from home-based business owners and therefore provides a more accurate account of the number of telecommuters. Our analysis focuses on the role of demographic characteristics, such as age, gender, ethnicity, household income, presence of children in the household and household size affect the workers' propensity to telecommute. We also look into the distribution of telecommuters across industries, occupations, and firms of various sizes and observe how professional experience and job tenure impact telecommuting probability. Finally, we analyze telecommuting frequency and how it effects the reduction of vehicle miles traveled (VMT) and gather perceptions of employees who currently don't work at home. In general, the survey confirms the major factors contributing to telecommuting, such as higher educational level and more professional experience, as well as a longer tenure with the company and one's supervisor. At the same time, the analysis shows that telecommuters are more likely to be male and have smaller households than nontelecommuters. This is surprising given the findings from previous studies. The survey also shows that as many as one-third of telecommuters are working on-site and telecommuting on the same day and therefore eroding VMT reduction from telecommuting. Finally, the data on workers who currently don't telecommute reveal a disconnect between workers desire and ability to telecommute, since less-educated workers are more enthusiastic about working at home than more educated ones while the latter are more likely to be able to telecommute. This discussion paper is one in a series of four RFF papers on telecommuting published in December 2004. In discussion paper 04-42, Walls and Nelson analyze data from five pilot cities enrolled in the "ecommute" program. In 04-44, Walls and Safirova review the empirical literature on telecommuting with a focus on trip reduction impacts. Finally, in 04-45, Nelson presents an assessment of institutional and regulatory barriers to using telecommuting in a mobile source emissions trading program. The studies by RFF are part of a larger report on the ecommute program completed by the Global Environment and Technology Foundation (GETF) for the U.S. Environmental Protection Agency. More information about the overall project can be found on the ecommute/GETF website: http://www.ecommute.net/program/.

In determining the marginal cost of congestion, economists have traditionally relied upon directly measuring traffic congestion on network links, disregarding any “network effects,” since the latter are difficult to estimate. While for simple networks the comparison can be done within a theoretical framework, it is important to know whether such network effects in real large-scale networks are quantitatively significant. In this paper we use a strategic transportation planning model (START) to compare marginal congestion costs computed link-by-link with measures taking into account network effects. We find that while in aggregate network effects are not significant, congestion measured on a single link is a poor predictor of total congestion costs imposed by travel on that link. Also, we analyze the congestion proliferation effect on the network to see how congestion is distributed within an urban area.

Economists have long advocated congestion pricing as an efficient way of allocating scarce roadway capacity. However, with a few exceptions, congestion tolls are rarely used in practice and strongly opposed by the public and elected officials. Although high implementation costs and privacy issues are alleviated as appropriate technologies are developed, the concerns that congestion pricing will adversely affect low-income travelers remain. In this paper, we use a strategic transportation planning model calibrated for the Washington, DC, metropolitan area to compare the welfare and distributional effects of three pricing schemes: value pricing (HOT lanes), limited congestion pricing, and comprehensive congestion pricing. We find that social welfare gains from HOT lanes amount to three-quarters of those from the comprehensive road pricing. At the same time, a HOT lanes policy turns out to be much more equitable than other road pricing schemes, with all income groups strictly benefiting even before the toll revenue is recycled.

Economists have long advocated congestion pricing as an efficient way of allocating scarce roadway capacity. However, with a few exceptions, congestion tolls are rarely used in practice and strongly opposed by the public and elected officials. Although high implementation costs and privacy issues are alleviated as appropriate technologies are developed, the concerns that congestion pricing will adversely affect low-income travelers remain. In this paper, we use a strategic transportation planning model calibrated for the Washington, DC, metropolitan area to compare the welfare and distributional effects of three pricing schemes: value pricing (HOT lanes), limited congestion pricing, and comprehensive congestion pricing. We find that social welfare gains from HOT lanes amount to three-quarters of those from the comprehensive road pricing. At the same time, a HOT lanes policy turns out to be much more equitable than other road pricing schemes, with all income groups strictly benefiting even before the toll revenue is recycled.