The purpose of tins report is to outline a methodology for the analysis of mode selection in freight transportation. This methodology is intended to partake of transportation corridor analysts, a component of demand analysis that is part of a national transportation process. The methodological framework presented here provides a basis on which specific models and calculation procedures might be developed. It also provides a basis for the development of a data management system suitable for corridor analysis and freight mode selection studies. The scope of the present report is limited to providing a methodological framework and does not include elaboration of specific calculating schemes or computer procedures.

Previous research studies have provided evidence of the non-uniformity of the value of time, which usually shows a decreasing trend as travel time increases. This work takes an in-depth look at thresholds and discontinuities in the value of time function. A theoretical framework is provided based on microeconomic theory. It is postulated that because of the multiple activities involved in an individual's activity pattern, and the minimum time requirements associated with these activities, there exist discontinuities in the travel cost function as the travel time encroaches upon the time originally assigned to other activities. The derivation of the indirect utility function of a trip is made in a multi-activity scenario, which shows the existence of discontinuous changes when the lowest time requirements of one or more activities are violated. In such cases, the activity may or may not be canceled. Two models are constructed depending on whether the cancellation is included. In Model 1, which assumes that the activity (of which the lowest time requirement is to be violated) cannot be canceled, the time assigned to the activity cannot be further reduced. As a result, further increase in travel time is at the expense of another activity. Therefore, Model 1 reflects a change of slope in the utility function. In the case of Model 2, the activity can be canceled. The cancellation of the activity results in a quantum change in utility function. Consequently, Model 2 reflects a change in slope together with a quantum decrease in utility.

The impact of the thresholds and discontinuities has long been overlooked, especially in intercity transportation. Using discrete choice modeling, empirical evidence of these discontinuities is found in air travel route choice. The thresholds where the discontinuities occur change with trip characteristics such as direction, and travel purpose. In general, the thresholds of business travelers are lower than those of leisure travelers. Additionally, there is evidence of a second threshold in the data. This is because as travel time keeps increasing after the first threshold is met, travel time starts to encroach on a second activity. The second threshold is hence possible as the binding condition may change again.

Because of the fewer variables involved in the estimation process, Model 1 is generally more stable and requires less computational effort. Based on the estimation results, whether the changes of utility at the thresholds are quantum (model 2) or not (model 1) remains an open question. Due to the limited data available for this study, the comparison results between the two models are tentative. More detailed data and in-depth research are needed to ascertain these results.

Numerical examples are used to illustrate the proposed models' impact on airline network design in the choice of hub location. For future research, suggestions are made to incorporate the notion of thresholds in travel survey design in order to provide better bases for estimating their values and their impact on traveler behavior.

This paper presents a functional description of PLANiTS (Planning and Analysis Integration for Intelligent Transportation Systems). The methodology consists of a process-based computer system that supports a series of mutually interdependent steps which progress toward developing and programming transportation improvement projects. PLANiTS can translate problems and goals to performance measures, examine possible competing and complementary actions that can address the problems, systematically evaluate the impacts of actions by using appropriate knowledge-based and model-based tools, and support human communication and interaction between planning group members.

The security of the transportation system depends on that of any of its components and how they are interlinked. But the securing of each component is oftentimes in the hand of the agency in whose jurisdiction it falls. Literature on reliability and security economics suggests that when security is defined by the weakest link in an interlinked system, then its level is determined by the agent with the highest cost-benefit ratio, and the other agents have the tendency to under-invest or free ride. When security is a function of total effort, then the opposite obtains and the reliability will depend on the agent with the lowest cost-benefit ratio. These conditions arise in urban transportation. This research explores agency investment behavior in multi-agency urban transportation systems develops guidelines for investments in security. The question to answer: is it preferable to let each agency operate its own security budget and make its own investment decisions or is this process better centralized?

Deployment of advanced technologies has enabled wireless internet access for commuters on various transportation modes. Such networked environments have enabled riders to engage in productive activities in transit. The ability to perform activities while traveling, especially paid work, may significantly affect the value of travel time (VOTT), with potential impacts on mode choice and commute patterns. In this study, we develop a model of the VOTT grounded in utility theory and activity choice analysis.

We use an efficiency factor which represents the ratio of the efficiency of working on transit to the efficiency of working at the workplace. This efficiency factor is used extensively in our models. Internet connection is expected to increase factor efficiency by providing access to real time information and enhanced communication. The model developed is used to explore the effects on VOTT of working in an enhanced networked environment while commuting. The results show that utility increases and VOTT decreases with increase in the efficiency of work while in transit, as is intuitive. An indirect utility function has been derived to represent travel on modes with internet access. The derivation permits an elegant introduction of internet access as an attribute in utility based choice models. Finally, the proposition that internet access may influence mode choice is corroborated by a survey conducted in June 2005 on Capitol Corridor trains.