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This paper provides a day-to-day analysis of the reliability of commuting time and trip scheduling under the Advanced Traveler Information System (ATIS). A simple network with parallel routes and bottleneck congestion is used to simulate the departure time and route choice decisions of commuters to minimize total travel time and scheduling delay cost. There are two major factors influencing the decisions of drivers in their departure time and route choices: their accumulated travel experience and information provided by ATIS. A simple experiment is carried for investigating trip-scheduling reliability of this network system.

Travel time variability has generally been recognized as one of the most important attributes in travelers' route choice decisions. In fact, many empirical studies have indicated that both passengers and freight carriers are strongly averse to travel time variability, because it introduces uncertainty to their route choice decisions. In this chapter, we examine the effect of incorporating travel time variability and risk-taking behavior into the route choice models and its impact on the estimation of travel time reliability under demand and supply variations.

Emergency vehicles should be planned to have smooth access to people's residences after a large scale disaster. This study proposes ANR, the Accessible Node Rate, which represents the ratio of the number of accessible nodes to total nodes in the network, as an indicator for evaluating the reliability of a local street network. Using the ANR, this study evaluates the urban districts of Nada Ward in Kobe City where the earthquake caused extensive damage, and proposes planning changes to provide the local street networks with higher reliability. Furthermore, in order to see if the ANR can be used for analyzing another city's reliability, a case study of Beppu City which is supposed to have the possibility of the same magnitude of earthquake, is examined. A system that supports traffic network editing and analysis for reducing the workload in a wider area is developed.

Ramp meters in the Twin Cities were turned off for 8 weeks in the Fall of 2000. This paper analyzes traffic data collected in this experiment on travel time variability with and without ramp metering for several representative freeways during the afternoon peak period. Travel time variability is generally reduced with metering. However, it is found that ramp meters are particularly helpful for long trips relative to short trips. The annual benefits from reducing travel time variability with meters are estimated to be $33.1 million, compared to the annual ramp metering costs of $2.6 million in the Twin Cities metro area. Thus, the impact on travel time variability should be captured in future ramp metering benefit/cost analysis.