Some evidence of transit demand elasticities

This paper draws together empirical evidence from a variety of sources about the magnitudes of transit price elasticities and cross-elasticities. A number of different practical measures of demand elasticity are first defined and some expectations about magnitude are discussed. Evidence is then collated from the analysis of transit operating statistics, from experience in demonstration projects and from attempts to develop cross-sectional models of demand and modal choice.In general, all of the limited evidence available suggests that transit demand is inelastic with respect to money price. Typically, ridership is significantly more sensitive to changes in the level of service (particularly door-to-door journey time) than to changes in fare, although service elasticities also are usually numerically less than unity.In broad terms, short-run direct fare elasticities are characteristically observed to lie within the range of -0.1 to –0.7. A more precise value in a particular instance will depend on a variety of factors in ways which largely support a priori notions. Thus in very large cities, central city areas, at peak hours, and in other circumstances where the prices of alternative modes are high, transit fare elasticities are usually numerically at the lower end of the range.Estimates of cross-elasticities (representing the volumes of transit traffic diverted to other modes by transit price increases) are much harder to come by, and in fact only a few very uncertain estimates are presented here.This paper is a condensation of an Urban Institute Working Paper of the same title (WP 708-52, November 1971). Opinions expressed are those of the author and do not necessarily represent the views of The Urban Institute or its sponsors.     

Users of a regional telephone-based traveler information system – a study of TravInfo™ users in the San Francisco Bay Area

This paper reports the results of a 1998 survey carried out among a small sample of people who had called the TravInfo Travel Advisory Telephone System (TATS) in April 1997 looking for current information about traffic conditions in the San Francisco Bay Area. The survey employed a series of tradeoff questions designed to identify the specific attributes of the information that the respondents felt to be most important, and to estimate the relative values that these users had for various possible information improvements. Despite the small size of the sample, it proved feasible to investigate how the implicit valuations placed on each attribute of the service (update frequency, extent of road coverage, and level of customization) varied among different user segments. For the most part, respondents appeared to value basic enhancements – those that establish an initial quality differential above the baseline set by free broadcast traffic information – more than they value further subsequent improvements. Overall, more frequent information updates are the highest priority among the range of possible enhancements explored in the survey, followed by an extension of coverage to include major arterials in addition to freeways. However, the evidence suggests relatively little value in door-to-door coverage – that is, coverage of streets beyond the freeway and major arterial networks. This research produced some estimates of the average monetary values ("willingness to pay") that the sample of current users attached to information improvements of various kinds. While these values varied among subgroups in ways that fit a priori expectations, it is not clear whether they provide an unbiased picture of the users' absolute levels of willingness to pay, such that they could be used reliably to inform (for example) information pricing decisions. The value of this research lies more clearly in the light it sheds on the relative structure of user preferences, and on the variations in preferences between information attributes and market segments. Overall, the authors conclude that the prospects for self-sustaining ATIS services are unclear. In response to a direct question, a majority of users (perhaps influenced by a strategic bias) indicated that they were unwilling to pay for ATIS services; some of these same people, however, indicated later that they might indeed be willing to buy a particular enhanced ATIS package, in direct competition with free broadcast services.     

氢燃料在铁道车辆的应用前景

以英国IC225车队为例,分析了氢燃料在铁道车辆上应用的技术要求,概述了氢燃料列车设计的可行性,并预测其在铁道车辆的应用前景.     

Urban transportation and the press: A survey of editorial opinion

The editorial opinions expressed in the news press can provide information on which issues are currently prominent concerns of the public, and on how public opinion may be aligned on those issues. A survey of all urban transportation-related editorials appearing in a sample of 155 U.S. newspapers during a period of 19 months in 1973–74 revealed that a number of issues related to transit financing, transit and highway investment, bicycles, and the transportation planning process were currently under debate in the urban press. This paper presents the survey's findings regarding the incidence and viewpoint of articles on these and other issues. Transit financing concerns clearly emerged as the most frequently discussed, and some agreement in editorial viewpoint was also found. The paper concludes with the authors' subjective observations on the scope and style of editorial discussion of urban transportation issues.This paper was prepared as background work for a recently-published essay on urban transportation problems (Kemp and Cheslow, 1976). The opinions expressed are those of the authors, and do not necessarily reflect the views of The Urban Institute or its sponsors.