Shinya Kurauchi

Driver’s Route Choice Behavior and its Implications on Network Simulation and Traffic Assignment

The principle of driver’s route choice has long been the shortest path with a fixed time penalty of a toll. It is also understood that traffic is assigned on the road network based on user equilibrium with perfect information assumption. This paper demonstrates two empirical studies that pose questions to these traditional assumptions, to better understand route choice behavior. Multi-class user equilibrium assignment with imperfectly informed drivers’ classes is applied to a metropolitan area network first. Next, route choice behavior is directly observed and analyzed using probe’ car data.

Inter-temporal analysis of household car and motorcycle ownership behaviors: the case in the Nagoya metropolitan area of Japan, 1981-2001

This study investigates household car and motorcycle ownership in the Nagoya metropolitan area of Japan. Bivariate ordered probit models of household vehicle ownership were developed using the data from the case study area at 3 time points: 1981, 1991, and 2001. The accessibility that is generally known to be correlated with vehicle ownership decisions is incorporated as an input for the proposed vehicle ownership model to investigate the potential relationship between them. The mode choice models for the area were first estimated to quantify the accessibility indexes that were later integrated into the vehicle ownership models. Inter-temporal comparison and temporal transferability analysis were conducted. Some of the major findings suggest that: 1) age and gender differences have become less important in modal choices and car ownership as motorization proceeds; 2) the accessibility seems to have a significant correlation with vehicle ownership; 3) car and motorcycle ownership may not be independent and may have a complementary relationship; and 4) the deep insights concerning the model selection are obtained from the viewpoints of the temporal transferability.

Forecasting Paratransit Ridership Using Discrete Choice Models with Explicit Consideration of Availability

In most developed countries, the population of the elderly and disabled is growing rapidly. These individuals require transportation service suited to their needs. Such service may be provided by applying emerging technologies to dial-a-ride transit. This research develops a methodology to quantitatively evaluate the impact of paratransit services on a traveler’s mode choice behavior. The mode choice model explicitly considers availability of alternative modes and includes latent factors to account for taste heterogeneity. Stated preferences are also used to elicit preferences for new paratransit services. The methodology is empirically tested with data collected in Winston-Salem, North Carolina. The model system developed is applied to evaluate the effect of improving service attributes and the impact of the introduction of new cost-effective modes on modal shares. Results of the policy analysis indicate that (a) transit policy changes, such as fare reduction, would have little effect on automobile driver and automobile passenger shares; (b) an improved reservation system for dial-a-ride services would produce shifts in mode share; (c) the proposed new bus deviation service was favored; (d) free bus service reduces dial-a-ride share; and (e) an increase in awareness of a dial-a-ride system would significantly increase its share.

Household car and motorcycle ownership in Bangkok and Kuala Lumpur in comparison with Nagoya

This study investigates household car and motorcycle ownership behaviours in the Asian metropolises of Bangkok and Kuala Lumpur (developing countries), and of Nagoya (developed country). Mode choice models are first estimated to calculate accessibility measures, and then car and motorcycle ownership models are estimated using bivariate ordered probit models with the accessibility measures as explanatory variables. Inter-regional comparisons and spatial transferability analysis are conducted. Results suggest that: (i) accessibility measures and car and motorcycle ownership behaviour are correlated; (ii) car and motorcycle ownership is substitutable in Bangkok and Kuala Lumpur, but is complementary in Nagoya; (iii) car and motorcycle ownership behaviour in Bangkok and Kuala Lumpur is similar and quite distinct from Nagoya; and (iv) car and motorcycle ownership behaviour in Nagoya in 1981 was closer than the ownership behaviour in Nagoya in 1991 and 2001 to the behaviour in Bangkok and Kuala Lumpur. Policy implications are also discussed.

The Suitable Index of Flow and Density in the Mixed Traffic

Some traffic indices were developed to consider the existence of vehicle variance either in the homogeneous or mixed traffic. This study investigates the proper index of flow and density in the mixed traffic. There are eight pairs of indices of traffic flow and density that will be compared, in which it was varied by the concept and the measurement interval. The concept was distinguished according to the respond to the variance of vehicles in the traffic analysis, and the measurement interval was differentiated over time and time-space. The traffic was observed over a short section of a road which set as the detection zone. All pairs of indices will be applied and evaluated on the Fundamental Diagram to describe the actual traffic state in the density-flow plane. Then, the R-square of each density-flow curve will be compared. The result shows that the existence of vehicle variance in the share of traffic can be described more properly by considering the projected area of vehicles. The index of flow and density which considers the projected area of vehicles can explain the actual traffic state more appropriately by increasing the R-square of the model. In addition, the result does not provide a significant difference between the measurement over time and time-space in a short section of the road.