排序方式: 共有24条查询结果,搜索用时 15 毫秒
21.
An exploratory analysis of commuters' activity and travel patterns was carried out using activity-based travel survey data
collected in the Washington, DC metropolitan area to investigate and estimate relationships among socio-demographics, activity
participation, and travel behavior. Structural equations modeling methodology was adopted to determine the structural relationships
among commuters' demographics, activity patterns, trip generation, and trip chaining information. Three types of structural
equations model systems were estimated: one that models relationships between travel and activity participation, another that
captures trade-offs between in-home and out-of-home activity durations, and a third that models the generation of complex
work trip chains. The model estimation results show that strong relationships do exist among commuters' socio-demographic
characteristics, activity engagement information, and travel behavior. The finding that significant trade-offs exist between
in-home and out-of-home activity participation is noteworthy in the context of in-home vs. out-of-home substitution effects.
Virtually all of the results obtained in this paper corroborate earlier findings reported in the literature regarding relationships
among time use, activity participation, and travel.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
22.
Travel behavior researchers have been intrigued by the amount of time that people allocate to travel in a day, i.e., the daily
travel time expenditure, commonly referred to as a “travel time budget”. Explorations into the notion of a travel time budget
have once again resurfaced in the context of activity-based and time use research in travel behavior modeling. This paper
revisits the issue by developing the notion of a travel time frontier (TTF) that is distinct from the actual travel time expenditure
or budget of an individual. The TTF is defined in this paper as an intrinsic maximum amount of time that people are willing
to allocate for travel. It is treated as an unobserved frontier that influences the actual travel time expenditure measured
in travel surveys. Using travel survey datasets from around the world (i.e., US, Switzerland and India), this paper sheds
new light on daily travel time expenditures by modeling the unobserved TTF and comparing these frontiers across international
contexts. The stochastic frontier modeling methodology is employed to model the unobserved TTF as a production frontier. Separate
models are estimated for commuter and non-commuter samples to recognize the differing constraints between these market segments.
Comparisons across the international contexts show considerable differences in average unobserved TTF values. 相似文献
23.
Chandra R. Bhat Konstadinos G. Goulias Ram M. Pendyala Rajesh Paleti Raghuprasad Sidharthan Laura Schmitt Hsi-Hwa Hu 《Transportation》2013,40(5):1063-1086
This paper develops and estimates a multiple discrete continuous extreme value model of household activity generation that jointly predicts the activity participation decisions of all individuals in a household by activity purpose and the precise combination of individuals participating. The model is estimated on a sample obtained from the post census regional household travel survey conducted by the South California Association of Governments in the year 2000. A host of household, individual, and residential neighborhood accessibility measures are used as explanatory variables. The results reveal that, in addition to household and individual demographics, the built environment of the home zone also impacts the activity participation levels and durations of households. A validation exercise is undertaken to evaluate the ability of the proposed model to predict participation levels and durations. In addition to providing richness in behavioral detail, the model can be easily embedded in an activity-based microsimulation framework and is computationally efficient as it obviates the need for several hierarchical sub-models typically used in extant activity-based systems to generate activity patterns. 相似文献
24.
Abdul Rawoof Pinjari Ram M. Pendyala Chandra R. Bhat Paul A. Waddell 《Transportation》2011,38(6):933-958
The integrated modeling of land use and transportation choices involves analyzing a continuum of choices that characterize
people’s lifestyles across temporal scales. This includes long-term choices such as residential and work location choices
that affect land-use, medium-term choices such as vehicle ownership, and short-term choices such as travel mode choice that
affect travel demand. Prior research in this area has been limited by the complexities associated with the development of
integrated model systems that combine the long-, medium- and short-term choices into a unified analytical framework. This
paper presents an integrated simultaneous multi-dimensional choice model of residential location, auto ownership, bicycle
ownership, and commute tour mode choices using a mixed multidimensional choice modeling methodology. Model estimation results
using the San Francisco Bay Area highlight a series of interdependencies among the multi-dimensional choice processes. The
interdependencies include: (1) self-selection effects due to observed and unobserved factors, where households locate based
on lifestyle and mobility preferences, (2) endogeneity effects, where any one choice dimension is not exogenous to another,
but is endogenous to the system as a whole, (3) correlated error structures, where common unobserved factors significantly
and simultaneously impact multiple choice dimensions, and (4) unobserved heterogeneity, where decision-makers show significant
variation in sensitivity to explanatory variables due to unobserved factors. From a policy standpoint, to be able to forecast
the “true” causal influence of activity-travel environment changes on residential location, auto/bicycle ownership, and commute
mode choices, it is necessary to capture the above-identified interdependencies by jointly modeling the multiple choice dimensions
in an integrated framework. 相似文献