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971.
有限理性视野下出行者出行方式选择分层Logit模型研究 总被引:1,自引:0,他引:1
在传统分层Logit模型的基础上,放松出行者完全理性的假设,基于有限理性满意决策准则,建立了多方式有限理性分层Logit(BRNL)模型,来描述出行者的方式选择行为.模型假设当方式间的成本差在无差异区间内时,出行者依据偏好或随机进行方式选择;否则,出行者将选择出行成本更小的交通方式.此外,提出了一种嵌套的相继平均算法对模型进行求解.最后,通过一个数值算例验证了模型的合理性和算法的有效性.研究结果表明,出行者并不总是选择出行成本最小的交通方式,其选择行为与出行者的理性程度和偏好有关,且理性程度越低,出行者对方式间的成本差越不敏感. 相似文献
972.
近年来,网约车发展迅速,而现有研究较少从市场角度理解用户对网约车的选择偏 好.本文构建了基于混合Logit选择模型,选取网约车依赖性、出行目的等出行相关属性,年龄等 个人社会经济属性为效用函数特征变量,假设到达时间、在车时间和费用为随机变量并服从对 数正态分布.使用D-efficient效率设计法生成问卷,在成都市开展网约车使用特征与选择偏好的 实证调查.基于观察数据标定模型,参数显著性及符号解释了城市综合交通背景下出行方式选 择的关键因素.对出租车和网约车费用进行边际效应分析,明确了价格变化对出行结构的影响. 相似文献
973.
Individuals processing the information in a stated choice experiment are typically assumed to evaluate each and every attribute offered within and between alternatives, and to choose their most preferred alternative. However, it has always been thought that some attributes are ignored in this process for many reasons, including a coping strategy to handle ones perception of the complexity of the choice task. Nonetheless, analysts typically proceed to estimate discrete choice models as if all attributes have influenced the outcome to some degree. The cognitive processes used to evaluate trade-offs are complex with boundaries often placed on the task to assist the respondent. These boundaries can include prioritising attributes and ignoring specific attributes. In this paper we investigate the implications of bounding the information processing task by attribute elimination through ignoring one or more attributes. Using a sample of car commuters in Sydney we estimate mixed logit models that assume all attributes are candidate contributors, and models that assume certain attributes are ignored, the latter based on supplementary information provided by respondents. We compare the value of travel time savings under the alternative attribute processing regimes. Assuming that all attributes are not ignored and duly processed, leads to estimates of parameters which produce significantly different willingness to pay (WTP) to that obtained when the exclusion rule is invoked. 相似文献
974.
The daily activity-travel patterns of individuals often include interactions with other household members, which we observe in the form of joint activity participation and shared rides. Explicit representation of joint activity patterns is a widespread deficiency in extant travel forecasting models and remains a relatively under-developed area of travel behavior research. In this paper, we identify several spatially defined tour patterns found in weekday household survey data that describe this form of interpersonal decision-making. Using pairs of household decision makers as our subjects, we develop a structural discrete choice model that predicts the separate, parallel choices of full-day tour patterns by both persons, subject to the higher level constraint imposed by their joint selection of one of several spatial interaction patterns, one of which may be no interaction. We apply this model to the household survey data, drawing inferences from the household and person attributes that prove to be significant predictors of pattern choices, such as commitment to work schedules, auto availability, commuting distance and the presence of children in the household. Parameterization of an importance function in the models shows that in making joint activity-travel decisions significantly greater emphasis is placed on the individual utilities of workers relative to non-workers and on the utilities of women in households with very young children. The model and methods are prototypes for tour-based travel forecasting systems that seek to represent the complex interaction between household members in an integrated model structure. 相似文献
975.
A tour-based model of travel mode choice 总被引:1,自引:0,他引:1
Eric?J.?MillerEmail author Matthew?J.?Roorda Juan?Antonio?Carrasco 《Transportation》2005,32(4):399-422
This paper presents a new tour-based mode choice model. The model is agent-based: both households and individuals are modelled within an object-oriented, microsimulation framework. The model is household-based in that inter-personal household constraints on vehicle usage are modelled, and the auto passenger mode is modelled as a joint decision between the driver and the passenger(s) to ride-share. Decisions are modelled using a random utility framework. Utility signals are used to communicate preferences among the agents and to make trade-offs among competing demands. Each person is assumed to choose the best combination of modes available to execute each tour, subject to auto availability constraints that are determined at the household level. The households allocations of resources (i.e., cars to drivers and drivers to ride-sharing passengers) are based on maximizing overall household utility, subject to current household resource levels. The model is activity-based: it is designed for integration within a household-based activity scheduling microsimulator. The model is both chain-based and trip-based. It is trip-based in that the ultimate output of the model is a chosen, feasible travel mode for each trip in the simulation. These trip modes are, however, determined through a chain-based analysis. A key organizing principle in the model is that if a car is to be used on a tour, it must be used for the entire chain, since the car must be returned home at the end of the tour. No such constraint, however, exists with respect to other modes such as walk and transit. The paper presents the full conceptual model and estimation results for an initial empirical prototype. Because of the complex nature of the model decision structure, choice probabilities are simulated from direct generation of random utilities rather than through an analytical probability expression. 相似文献
976.
在文献[4]的基础上,进一步讨论了回转体外形的参函数逼近方法。利用这种方法可以自然满足边界条件,简化逼近计算;可以对给定的型值进行直观的检查和光顺,提高逼近精度;可以显示出节点的合理部位,减少节点选择的盲目性。 作为文献[4]的继续和补充,还给出了圆锥端头截体和平端头截体的数学表达式。 相似文献
977.
978.
The purpose of this study is to examine the spatial and temporal characteristics of weekend work episodes. Specifically, we
examine whether individuals work over the weekend and, if they work, whether they work at home or outside the home. We also
model the time of day of weekend work. The empirical analysis in the paper is based on the 2000 San Francisco Bay Area Travel
Survey. The results indicate the important effects of day of week/seasonal effects, individual demographics, work-related
variables, household characteristics, and location variables on weekend work participation characteristics. The models estimated
in the paper may be embedded within a larger weekend activity-travel pattern forecasting model system. 相似文献
979.
驾驶员的路径选择行为是影响交通诱导成效的一个关键因素。建立了诱导信息条件下驾驶员路径选择行为模型,仿真分析了诱导信息和驾驶员的经验对驾驶员路径选择行为、路网交通流分布、系统整体效益的影响。研究结果表明,随着出行次数的增加,2条路径的交通流波动逐步减小,系统总行程时间逐渐减少,逐渐趋于系统均衡。驾驶员的长期经验、诱导信息的长期准确对驾驶员的路径选择行为、系统均衡具有重要影响。 相似文献
980.