Professor Koppelman's Research


Professor Koppelman's research is focused on the analysis and prediction of personal travel behavior based on the development of activity-based travel demand models for urban travel and multi-dimensional choice models for intercity travel and air traveler preferences for carriers, schedule and classes..  His research includes development of extended logit choice models which allow flexible patterns of substitution and differences among individuals and travel contexts and their application to complex choice problems.

Selected publications are accessible by selecting the following subject titles:

Activity-Based Travel Demand Models
(11 papers are listed under this topic)
Urban travel research has shifted to a structure based primarily on the role of travel in providing access to activity locations to satisfy household needs for participation in work, household maintenance, social/recreational and other activities.

Extended Logit Discrete Choice Models
(7 papers are listed under this topic)
Random utility maximization discrete choice models are widely used in transportation and other fields to represent the choice of one among a set of mutually exclusive alternatives. Early development of choice models was based on simplifying assumptions which led to the widely used multinomial logit but limited the ability to represent the structure of the choice process.  This research contributes to the development of closed form models which relax the assumption of the multinomial logit model to provide a more realistic representation of choice probabilities within a closed form framework.

Urban Travel Demand
(4 papers are listed under this topic)
Traditional urban travel demand models have been enhanced through the use of disaggregate data, attitudinal measures and discrete choice models.

Intercity Travel Demand
(7 papers are listed under this topic)
The choice of intercity travel mode is important to the assessment of investment in new roadways, intercity rail and high speed rail services and intercity air terminals and service.  These models reflect the complexity of the intercity travel decision.

Air Traveler Preferences
(8 papers are listed under this topic)
Intercity air travelers face a myriad of choices including choice of carrier, time of day, day of week and class of service.  This research examines issues important to travelers in choosing alternatives along these dimension and addresses the response of travelers to the inability to book their preferred alternative.