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991.
K. Obeng 《Transportation》2011,38(2):191-214
This paper uses an indirect production function to decompose the effects of subsidies on output into the lump-sum, cost and inefficiency effects. Using 2006 data for U.S. transit systems it estimates an indirect production function and uses the results to calculate these effects. It finds that the lump-sum effects exceed the other effects and that the average total effect of the subsidies is a 4.72% increase in output. The range of the output change shows that in many transit systems the output increases from the subsidies are quite large. The paper suggests that reductions in allocative inefficiencies from the subsidies would result in very large increases in output. 相似文献
992.
At transit terminals where two routes interchange passengers, total system costs may be reduced by allowing some “slack” time in the vehicle schedules to decrease the probability of missed connections. Transfer cost functions are formulated and used to determine optimal slack time for simple systems with transfers between one bus route and one rail line. Some analytic results are derived for empirical discrete and Gumbel distributions of bus arrival times. Relations between the optimal slack times and headways, transfer volumes, passenger time values, bus operating costs, and standard deviations of bus and train arrivals are also developed numerically using normally distributed arrivals. However, the proposed numerical approach can optimize slack times for any observed arrival distributions. The results provide some guidelines on desirable slack times and show that schedule coordination between the two routes is not worth attempting when standard deviations of arrivals exceed certain levels. Possible extensions of this work are suggested in the last section. 相似文献
993.
A new model system dealing with trips of length up to 100 km has recently been developed in Norway. A new way of dealing with
seasonal passes for public transport is used in the travel-to-work model. The objective was to account for the fact that a
respondent that posses a seasonal pass for public transport may behave as if public transport is free on the day they report
a travel diary. On the other hand, we can not assume that public transport is free for respondents that used other modes of
transport or that public transport is free to alternative destinations. This problem was solved by defining seasonal pass
as a separate alternative in the form of a nest that included all modes of travel. The cost of a seasonal pass is a common
cost for all modes in the nest and will thus not affect the choice within the nest. The estimation of this specification is
compared with the more common approach of assigning an average cost per day based on the cost of a monthly pass and the number
of workdays in a month. The comparison indicates that the “average cost per day” approach may produce biased estimates for
several parameters. It also turns out that the cost parameter for seasonal pass is higher than the parameter for “out of pocket”
cost, probably reflecting that there will be some uncertainty with respect to the actual use of a seasonal pass. 相似文献
994.
While much of the scholarly literature on immigrants’ travel focuses on transit use, the newest arrivals to the United States make over twelve times as many trips by carpool as by transit. Using the 2001 National Household Travel Survey and multinomial logit mode choice models, we examine the determinants of carpooling. In particular, we focus on the likelihood of carpooling among immigrants—carpooling both within and across households. After controlling for relevant determinants of carpooling, we find that immigrants are far more likely to form household carpools than native-born adults and also are more likely than the native-born to form external carpools (outside the household). Moreover, when faced with the options of carpooling and public transit, immigrants—even recent arrivals—appear to prefer carpools over transit more strongly than the native born. 相似文献
995.
Nazneen Ferdous Abdul Rawoof Pinjari Chandra R. Bhat Ram M. Pendyala 《Transportation》2010,37(3):363-390
This paper proposes a multiple discrete continuous nested extreme value (MDCNEV) model to analyze household expenditures for
transportation-related items in relation to a host of other consumption categories. The model system presented in this paper
is capable of providing a comprehensive assessment of how household consumption patterns (including savings) would be impacted
by increases in fuel prices or any other household expense. The MDCNEV model presented in this paper is estimated on disaggregate
consumption data from the 2002 Consumer Expenditure Survey data of the United States. Model estimation results show that a
host of household and personal socio-economic, demographic, and location variables affect the proportion of monetary resources
that households allocate to various consumption categories. Sensitivity analysis conducted using the model demonstrates the
applicability of the model for quantifying consumption adjustment patterns in response to rising fuel prices. It is found
that households adjust their food consumption, vehicular purchases, and savings rates in the short run. In the long term,
adjustments are also made to housing choices (expenses), calling for the need to ensure that fuel price effects are adequately
reflected in integrated microsimulation models of land use and travel. 相似文献
996.
Smart card systems have become the predominant method of collecting public transport fares in Japan. Transaction data obtained
through smart cards have resulted in a large amount of archived information on how passengers use public transportation. The
data have the potential to be used for modeling passenger behavior and demand for public transportation. This study focused
on train choices made by railway passengers. If each passenger’s train choice can be identified over a long period of time,
this information would be useful for improving the customer relationship management of the railway company and for improving
train timetables. The aim of this study was to develop a methodology for estimating which train is boarded by each smart card
holder. This paper presents a methodology and an algorithm for estimation using long-term transaction data. To validate the
computation time and accuracy of the estimation, an empirical analysis is carried out using actual transaction data provided
by a railway company in Japan. The results show that the proposed method is capable of estimating passenger usage patterns
from smart card transaction data collected over a long time period. 相似文献
997.
998.
The paper reports a modelling system to simulate goods movements at an urban scale. It allows joint analysis of choices made
by end-consumers (assumed to be families) and retailers. These movements are examined at two levels: analysis of commodity
flows, in terms of quantity, generated by the consumption of commodities; analysis of commodity flows, in terms of vehicles,
due to restocking. The first level allows us to calculate the goods quantity flows due to consumption and restocking; the
second level allows us to determine the service, vehicles used and target time, as well as the route chosen for restocking
sales outlets in order to estimate vehicle flows on the urban/metropolitan transportation network. The modelling system is
a multi-step model and considers a disaggregated approach for each decisional level. 相似文献
999.
Carlton Basmajian 《Transportation》2010,37(1):59-84
Though driving to and from work has become a prevalent experience in the lives of individuals in every metropolitan region in the US, much remains to be learned about the activity from the perspective of the drivers. To increase our understanding of the motivation for certain travel behaviors, we must first know something about what those drivers experience. The existing literature explains much, but the application of new methodologies could improve our ability to explain the willingness of individuals to choose to drive through increasingly congested road networks. The results of this study of oral histories of 12 women commuters underscore the idea that commute should be seen as a set of subjective behaviors that contradict some existing assumptions about why individuals commute. 相似文献
1000.
Mass transit projects are often a top contender of many cities to meet their increasing demand for travel. Despite the global
trend of privatization, mass transit services, as public goods, remain largely being provided and operated by the public sector.
Hong Kong is one of the few exceptions that all mass transit services are commercially operated. Both rail and bus services
in Hong Kong are reputable for their quality and profitability, often serving as benchmarks for new projects. In this study,
we investigate the factors contributing to this success. In particular, we ascertain the quality of transit service provision
by the private sector over the past two decades. Then, we conduct an in-depth analysis of the account books of leading railway
and bus operators in Hong Kong so as to shed light on their financial viability. Through this study, we hope to present crucial
factors for providing financially viable private transit services. 相似文献