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111.
112.
Traffic congestion in the world's metropolitan areas is going from bad to worse. Urban/suburban transportation has become like the weather; people talk a lot about it but shrug it away as something they can't do much about. This is a world-wide phenomenon, as motor vehicle use grows, and as urban sprawl continues.  相似文献   
113.
Using the concept of generalised costs to reflect quality in rail services, we consider the level of provision and quality of these services in the various forms they may take in a privatised environment within a model where we assume linear and separable demand and cost functions for analytical simplicity. Using the Pareto-efficient output and quality outcomes under a fully integrated system for reference (as well as those for a fully integrated profit-maximising monopolist) we show that if either bilateral monopoly or complementary monopoly emerge as a market structure the output of train services and their quality will generally fall. In the case of the emergence of both bilateral monopoly and complementary monopoly our analysis again suggests poor welfare outcomes. The implication that can be drawn from our analysis is that a regulator of a privatised rail system faces some severe problems if she is to attain the appropriate welfare targets.  相似文献   
114.
The work described was undertaken as part of the CASSIOPE project in the EC DRIVE programme. A range of fare collection procedures in public transport is described, and the importance of these for data collection by operators is stressed. It is suggested that such data management could be standardized and to this end four case studies were carried out in different European cities. Data models were built for each city, and these models are merged into a preliminary version of a generalized model. The need and uses for such a fare collection data model is explained.  相似文献   
115.
This paper examines the impact of policy changes in the funding of New Zealand public transit modes.These changes, introduced in 1983, are evaluated in terms of the net incidence of public transit subsidy assistance, taking into account its source of funding and the income class of those commuters benefiting from the subsidy. The general conclusion is that the net incidence of subsidy assistance remains progressive (i.e., a transfer from high to low income commuters) following the introduction of shared funding on the predominant public transit modes (rail and bus), sourced from income tax (central government) and property tax (regional/local government). However, because of the predominance of medium to high income commuters on rail vis-a-vis bus and the traditional source of funding on these modes in terms of income tax (a progressive tax source) and property tax (a regressive tax source), the degree of progressivity previously associated with public transit subsidies has now substantially reduced.The analysis and opinions expressed in this paper are the responsibility of the author alone and do not purport to represent the views of the Ministry of Transport.  相似文献   
116.
Using data on state highway expenditures and employment from 30 Minnesota non-metropolitan counties over a 25-year period, possible interactions between transportation and employment are investigated. While crosssectional analysis suggests no significant interactions, causality tests and time-series analyses indicate that highway expenditures affect manufacturing and retail employment, and employment influences expenditures. Although expenditure increases cause employment improvements in the short-term, long-term effects are less favorable. Highway expenditures respond quickly to increased needs caused by retail improvements.  相似文献   
117.
118.
This paper argues for interval, rather than point, estimation when calibrating some variants of the trip distribution “gravity” models. Analytic expressions are derived for the approximate asymptotic covariances of least squares and maximum likelihood estimates of the parameters in the impedance function under a variety of conditions. A comparative numerical example, and an application using migration flows, are also presented.  相似文献   
119.
This is the second of two background papers sponsored for the Symposium by the Administrative Commission for the north of the Netherlands. Its purpose is to provide an indication of the effects of the proposed high speed rail line between Amsterdam, Groningen and Hamburg on employment in the corridor. The authors first review the techniques of forecasting these effects discussed in the literature. The potentials approach is adopted for their analysis, the mathematics and underlying assumptions of which are presented. Finally, this model is run to provide an estimate of the impact on regional employment of three variants of the proposed rail line.  相似文献   
120.
The choice of fare policy is more flexible in personal rapid transit than in conventional transit and has some unique aspects. The implementation of fare policies as a function of distance are discussed, and, following a discussion of how the fare would be collected in a PRT system, consideration is given to whether the fare should be per person or per vehicle.  相似文献   
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