TRANSPORTATION DEMAND FORECASTING

INNOVATIONS IN

TRAVEL MODELING 2008

 

INNOVATIONS IN TRAVEL MODELING 2008

PORTLAND, OREGON

JUNE 22 - JUNE 24

 

 

Jointly sponsored by the Transportation Research Board, Federal Highway Administration, Federal Transit Administration, Oregon Department of Transportation, Portland Metro, and Portland State University.

This conference built on the highly successful ITM06 conference in Austin, examining innovative and promising advances in travel modeling, with an emphasis on moving state-of-the-art research into practice. The conference focused on an open exchange of ideas between researchers and practitioners regarding recent advances in travel modeling, opportunities and challenges related to implementation, and directions for further research and development. Transportation professionals involved in the research, teaching, implementation, and use of travel models found this conference timely and informative.

The conference included tracks focusing on activity-based models, linking demand and dynamic network models, communicating forecasts, policy and pricing analyses, and freight modeling. Workshops on activity-based models and climate change modeling were held.

The program can be found here.  The following themes will be addressed at the conference:

Linking Demand and Dynamic Network Models

Recent methodological advances and technological innovation have increased the relevance of dynamic traffic assignment within the travel demand modeling arena. However, currently there are few examples that integrate demand models with the supply side network models with an approach that takes advantage of the complexity and sensitivity of each side. Presentations were related to methodological advances and practical applications of linking travel demand and dynamic network models. This included, but was not limited to, linking activity-based travel demand models with dynamic traffic assignment. Topics of particular interest included:

  • Practical applications of linking travel demand and dynamic network models, and
  • Methodological advances in the integration of travel demand and dynamic network models

Approaches to Modeling Traveler Response to Road Pricing

The objective of this theme was to stimulate discourse on innovative methods for modeling traveler response to demand management policies in general, with an emphasis on road pricing policy scenarios.  While it is widely recognized that the classical trip-based travel demand model is ill-suited to represent either the demand management stimuli or the traveler response, there is a clear lack of consensus on how to specify a model that would be well-suited for such analysis.  Objectives included:

  • Incorporating model sensitivity to variable pricing schemes, based on either time-of-day or congestion levels;
  • Intra-personal variability in the implicit value of time for different activity contexts or decision elements (e.g., route, mode, destination, frequency, trip or activity purpose);
  • Incorporating reliability as an attribute of road pricing alternatives;
  • Inter-personal variability in response to road pricing by traditional socio-economic attributes, or hybrid lifestyle groupings;
  • Information and communication technology impacts on road pricing response;
  • Employer or institutional effects on road pricing response; and
  • Long-term responses to road pricing as reflected in land development patterns, household and workplace locations, or auto ownership.

Climate Change Modeling

Increased emphasis on climate change is putting new demands on transportation policy and travel demand modeling. Presentations addressed these challenges, for example work integrating travel demand, land use, air quality, and climate change models or emphasizing the necessary modifications of these models.

Communicating Forecasts

How do transportation professionals reconcile increasingly sophisticated travel demand forecasting models with strengthened requirements for meaningful public involvement? Although efforts to advance modeling practices over the last decade are beginning to pay off, little attention has been given to improving methods for communicating the forecasts made from these models. Finding more effective ways for communication is critical to elevating the quality of public involvement programs and ultimately the quality of transportation planning decisions. More sophisticated modeling techniques, including activity-based models and micro-simulation, magnify the communication challenges but also offer new opportunities.

Transportation professionals face two key challenges with respect to communicating forecasts:

  • How to explain travel demand forecasting models so that the public can understand them.  Often described as a “black box,” the inner workings of these models are mysterious to the public, decision makers, even professionals not directly involved in modeling.  Poor understanding of models can lead to their over-use, under-use, and general misuse in the planning process.
     
  • How to present the forecasts produced by these models so that the public can understand them.  Models produce reams of data that must be summarized in ways that help the public and decision makers understand the differences between plan alternatives or the effectiveness of proposed projects in meeting performance goals.  The quality of the presentation of forecasts can itself significantly influence the planning process.

 

PRESENTATIONS & PAPERS 

The presentations and papers from the conference will be posted here as they become available.  Please check back for these.

 

Corrections?  Email us.

Last update 7/23/2008