In this paper we firstly review general decision principles under uncertainty and apply them to route choice decisions. Risk-averse behaviour leads to the description of route choice a game. The difference between games against demons and nature are pointed out by distinguishing when disruptions on the chosen route might be related to the traveller’s behaviour or not. It is argued that in many cases the traveller has some (limited) information about the connection between attack likelihood and routing, meaning that pure games against demons are rare for practical applications. The paper therefore extends the game theoretic literature on route choice by formulating a generalised model. The model allows for games against multiple demons and consideration that some links might be safer than others. It is shown that games against nature and the Bell (2007) model can be derived as limiting cases. Results are illustrated with an example network.

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Motivated by the taxi refusal problem, this paper presents a new idea of bidding for taxi services through double auction. This is equivalent to a variable surcharge policy as opposed to the existing situation of a fixed surcharge paid in addition to a regular meter fare. Unlike an auction for normal commodities, time-cost is relevant in an auction for taxi services. Thus, the typical design of an auction may not be suitable for a taxi auction. This paper examines one of the problems of auction design: design of information content for the user interface. We conducted laboratory experiments to investigate the effect of different levels of information content. We found that the fixed surcharge policy was outperformed by the variable surcharge policy for most of the values of the surcharge considered. Moreover, there is a significant time-cost effect, and providing bidders with greater information leads to the lowest average transaction price.

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This paper develops an enhanced sequential logit model to depict the customer-search behavior of vacant-taxi drivers. This model considers that vacant-taxi drivers can change the choices that they make on their way to a designated district. Global positioning system trip data from 460 urban taxis were extracted to calibrate the model and to verify the factors underlying the drivers’ search decisions. The findings reveal that the proposed sequential logit model is capable of predicting the search paths of vacant-taxi drivers. This model form is considered to be more informative for policy makers who aim to study search paths and the associated traffic congestion contributed by taxis in each district.

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This study surveys and analyzes the characteristics of the carsharing market in Japan, focusing on cooperation among the stakeholders in the Japanese market. Twenty-three individuals from 10 organizations associated with the carsharing industry were interviewed, including carsharing operators, rail operators, bus operators, and local and central government representatives from July to August 2010. The results show that the stakeholders recognize two types of carsharing: a primary-mode-based system and a secondary-mode-based system. No carsharing operator has any plan to cooperate with the other operators currently, and the perceptions and expectations of the operators are different from those of the national government. Although local governments have a willingness to promote carsharing, they find difficulties in doing so because they worry about uncertainties regarding the effects of carsharing. Finally, this study summarizes three potential cases where cooperation is required among stakeholders in the urban carsharing market.

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This paper examines the influences of environmental consciousness and attitudes to transportation on electric vehicle purchase intentions. A multiple-indicators?multiple-causes model and a latent-class nested logit model with two segments were estimated using data obtained through a web-based questionnaire survey in the Chukyo Area of Japan. Results reveal that both environmental consciousness and attitudes to transportation significantly affect an individual’s EV buying intentions. Specifically, for the segment of mostly auto-dependent householders, environmental consciousness has strong negative relationships with intention to buy an EV as a replacement. The results provide insight for the design of policies aiming at promoting the adoption of EVs.

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This paper aims to identify the underlying factors in the acceptability of public transport improvement, office-based transport service, and fiscal policy measures using a framework of behavioral theories. The findings are based on results of a questionnaire survey, factor analyses, and structural equation modeling. This paper develops a joint-structural model of the theory of planned behavior and the norm-activation model, and explains the significance of behavioral theories in predicting people’s behavioral intentions and response to travel demand management (TDM) measures. The findings reveal that attitudes toward public transport, perceived behavioral control over public transport, and social and personal norms are significant determinants of people's behavioral intentions regarding TDM measures. Other factors include social status traits, flexibility and freedom, income and traveling mode. Some intervention packages have been suggested to activate different attitudes and norms for effective behavioral change. This study should provide a deep understanding of significant factors that need to be considered in implementing TDM measures in developing countries.

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This paper analyzes the characteristics of the Segway's running behavior by means of experiments conducted on a test course, with a focus on the difference in the time that the participants had been riding the Segway. Trajectory data for the Segway were collected from 14 male subjects, with five running situations being assumed: acceleration, deceleration, slalom running, overtaking and passing pedestrians, and emergency braking. The experimental results show that there is a difference between beginners and experienced users in deceleration and rotational behavior. The emergency braking experiments showed that there is not much difference according to experience, and furthermore, they indicated that there was a similarity to the stopping behavior of a bicycle. These results are expected to be useful in designing a Segway training scheme and evaluating the use of the Segway on public roads as well as appropriate rules and regulations such as using a microscopic traffic simulation.

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In this study, we explore novel methods of evaluating pedestrian environments. Pedestrians' behaviors and expressions are examined as indicators of walking space quality; such visual information is superior to questionnaire data because it can be obtained without the target's knowledge. These behavioral data, along with stress response and questionnaire data, were collected from pedestrians on selected streets in Japan. Results indicated diverse pedestrian behavior on a street where the walking environment had been improved. Analysis of pedestrians' expressions showed that pedestrians were more likely to smile in the improved environment. Thus, these findings suggest that pedestrians' behaviors and expressions may indicate the quality of the pedestrian environments.

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