Passengers’ willingness to pay for airport ground access time savings

There are cases when passengers are willing to pay a premium to reduce the travel time, in particular when the trip has to be made. This paper aims to provide insight into factors that determine passengers’ willingness to pay to reduce travel time for their ground access to an airport. A methodology is developed that comprises two steps: the identification of the passengers with zero willingness to pay and from the rest the estimation of the additional price they are willing to pay to reduce their travel time. For the first step a Probit model was formulated and for the second a linear regression model. To this purpose, data has been collected employing stated preference from passengers at the Athens International Airport. It has been found that a high percentage of passengers have zero willingness to pay, and of the remaining ones those using public transport have a significant willingness to pay to reduce access travel time. The methodology and the models are structured in such a way that their transferability to any airport environment is possible, thus providing a useful tool for decisions relating to airport ground access measures.     

A stated preference examination of time of travel choice for a recreational trip

A stated preference experiment was performed in Calgary in Canada to examine how people are influenced in the selection of a departure time for a hypothetical trip to see a movie. A total of 635 complete observations were obtained. In each observation the respondent was presented with a set of possible departure time scenarios and asked to indicate the order of preference for these scenarios. Each scenario was described by specifying the automobile travel time, the expected arrival time relative to the movie start time, the parking cost, the probability of being at least ten minutes late for the movie and the length of time the movie had been running. This forced the respondent to trade off between conditions regarding these attributes. Age, gender and frequency of movie attendance were also recorded. The observations thus obtained were used to estimate the parameter values for a range of alternative utility functions in logit models representing this choice behaviour. The results indicate that all of the attributes included have significant effects on departure time choice in the situation being considered. They also indicate that travellers are prepared to arrive roughly two minutes early for each minute of travel time saved; that the money value of driving time for trips to recreational activities is about half that for trips to work; that one additional percent in the probability of arriving late is equivalent to roughly 0.20 Canadian dollars or 1.93 minutes drive time; and that there is a preference for a non-zero expected early arrival time regardless of the associated probability of arriving late. Some of these results are novel and others are consistent with findings for work trips in work done by others, which is seen to add credence to the approach being used here.     

Modelling users’ behaviour in inter-urban carsharing program: A stated preference approach

In this paper, the effects of a inter-urban carsharing program on users’ mode choice behaviour were investigated and modelled through specification, calibration and validation of different modelling approaches founded on the behavioural paradigm of the random utility theory. To this end, switching models conditional on the usually chosen transport mode, unconditional switching models and holding models were investigated and compared. The aim was threefold: (i) to analyse the feasibility of a inter-urban carsharing program; (ii) to investigate the main determinants of the choice behaviour; (iii) to compare different approaches (switching vs. holding; conditional vs. unconditional); (iv) to investigate different modelling solutions within the random utility framework (homoscedastic, heteroscedastic and cross-correlated closed-form solutions). The set of models was calibrated on a stated preferences survey carried out on users commuting within the metropolitan area of Salerno, in particular with regard to the home-to-work trips from/to Salerno (the capital city of the Salerno province) to/from the three main municipalities belonging to the metropolitan area of Salerno. All of the involved municipalities significantly interact each other, the average trip length is about 30 km a day and all are served by public transport. The proposed carsharing program was a one-way service, working alongside public transport, with the possibility of sharing the same car among different users, with free parking slots and free access to the existent restricted traffic areas. Results indicated that the inter-urban carsharing service may be a substitute of the car transport mode, but also it could be a complementary alternative to the transit system in those time periods in which the service is not guaranteed or efficient. Estimation results highlighted that the conditional switching approach is the most effective one, whereas travel monetary cost, access time to carsharing parking slots, gender, age, trip frequency, car availability and the type of trip (home-based) were the most significant attributes. Elasticity results showed that access time to the parking slots predominantly influences choice probability for bus and carpool users; change in carsharing travel costs mainly affects carpool users; change in travel costs of the usually chosen transport mode mainly affects car and carpool users.     

Improved Urban Inhabitant Travel Demand Model and Its Application

Transport planners often need to forecast the influence of the transport policies on travel demand, e.g., construction of a new transport alternative, changing public transit fares, or imposing road pricing schemes. Stated preference (SP) surveys are frequently adopted by transport planners for the analysis of the impact of transport policies on travel demand. However, evidence suggests that preferences derived from SP surveys are contingent on context, which indicates that trip makers may show asymmetric preferences for different levels of services. The objective of this article is to propose an alternative conceptual framework for travel demand analysis. It is expected that travel behavior may be heterogeneous across trip makers; response (or parameter of) to the level of service is defined as a function of the attributes of the trip makers. It is also aimed to propose some urban transportation policies based on a new type of discrete choice model. In an empirical demonstration, the panel data obtained from commuters in Lanzhou, China, are used, and support is obtained for several predictions on why behavioral intentions are, or are not, implemented.     

投资者风险投资行为选择

为更好地指导投资者,从行为金融学的角度,通过对投资者的风险规避效用曲线、期望效用、投资净现值和投资机会成本的分析,探讨了投资者风险态度的界定、阶段性投资工具配置、投资决策中机会成本的把握和投资期权的运用等影响投资者风险投资行为选择的因素.研究表明:投资者的风险偏好直接影响其对风险性收益的追求,并反映了投资者承受风险的心理临界;随着风险企业的发展,投资者以股权、债权的投资分别有减少、增加的趋势;在风险企业(项目)单位产出价格不变的前提下,投资者保持还是行使期权执行权力,取决于投资机会成本与净投资收益比较的高低;反之,投资等待还是加大投资的趋向将随单位产出价格的降低或提高而增强.     

A study of carpooling behaviour using a stated preference web survey in selected cities of India

This paper analyses how people perceive the idea of carpooling and evaluate preferences while making a decision to join a carpool. Analysing data from a web-based stated preference survey in India reveals that cognitive attitudes play a significant role in evaluating the perceived advantages and disadvantages of carpooling whereas intentions to carpool are associated with perceived negative evaluations. A factor analysis identifies two latent attitudinal factors: a ‘time–convenience’ factor that discourages carpooling and a ‘private–public cost’ factor that encourages carpooling. The study analyses the influential attributes – extra travel time, walking time to reach meeting point, waiting time at pickup point and cost savings – as explanatory variables for the utility of carpooling. Cost savings prove to be the most significant attribute when combined with other attributes, followed by extra travel time. The study provides the implications to policy-makers of designing promotional tools to improve the propensity of carpooling among single occupant vehicle drivers.     

基于交互式多目标遗传算法的混凝土桥面板维修优化

为了保证桥梁结构安全,并使维修效果最好,研究了如何确定桥面板最佳维修策略的问题。建立了桥面板维修的多目标优化模型。提出一种基于交互式遗传算法的维修策略优化方法,通过非精确偏好信息引导遗传搜索,使种群朝着多个目标的最佳综合性能进化。引入适应值共享方法增加种群的多样性,最终获得符合决策者偏好的解集。并通过算例进行了分析验证。结果表明,基于交互式多目标遗传算法的混凝土桥面板维修优化方法可以在有限的桥梁维修资源和良好的维修效果之间进行折衷,不仅获得一组比较理想的维修方法组合,还可以考虑决策者的个人倾向,降低了维修策略的选择难度,为桥梁管理者提供了有力的决策支持。     

MaaS出行选择倾向性研究

为探索MaaS出行下,用户对不同交通出行方式组合的选择倾向性及其影响因素,针对目标用户设计了网络问卷,并回收233份有效问卷,筛选得出1个因变量和14个自变量,借助SPSS软件清洗数据并建立多项Logit模型,数据分析结果表明月生活开销和距离因素是促成用户选择MaaS不同出行方式组合的关键因素。     

Extending stated choice analysis to recognise agent-specific attribute endogeneity in bilateral group negotiation and choice: a think piece

This paper is a think piece on variations in the structure of stated preference studies when modelling the joint preferences of interacting agents who have the power to influence the attribute levels on offer. The approach proposed is an extension of standard stated choice methods, known as ‘stated endogenous attribute level’ (SEAL) analysis. It allows for interactive agents to adjust attribute levels off a base stated choice specification that are within their control, in an effort to reach agreement in an experimental setting. This accomplishes three goals: (1) the ability to place respondents in an environment that more closely matches interactive settings in which some attribute levels are endogenous to a specific agent, should the modeller wish to capture such behaviour; (2) the improved ability of the modeller to capture the behaviour in such settings, including a greater wealth of information on the related interaction processes, rather than simply outcomes; and (3) the expansion of the set of situations that the modeller can investigate using experimental data.

基于决策场理论的出行者动态决策行为研究

为了研究出行者进行路径选择时的动态决策过程,本文采用决策场理论,研究 了多属性条件下,机动车出行者的微观和宏观动态决策行为.分析了决策场理论的基本模 型,构建了出行者动态决策行为场景和框架,以历史出行时间、预测出行时间和两者综合 值作为出行者决策的路径属性,并根据属性与实际出行时间的差值为依据,提出了出行 者注意力权重矩阵计算方法.通过算例分析发现,自由流出行时间对出行者决策影响较 大,出行者对路径属性的依赖性非常强,决策过程中存在路径偏好反转的现象,表明出行 者动态决策过程是随时间不断变化的,路径选择是时间累计的结果.