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12 I N N O VAT I O N S I N T R AV E L D E M A N D M O D E L I N G , V O L U M E 1 extremely quickly. Options to "transporting" are becom- greater interplay today between public and private own- ing more viable. Spatial, separation, and mitigation activ- ership and management of different modes of the trans- ities must be the base for forecasting. Pricing and portation system. economic models are becoming more varied and complex. Available technologies are shortening the response times and the dispersion times. These items need to be INNOVATIONS IN MODELING examined in travel demand modeling and may impact the fundamental assumptions and parameters that are Brian Gardner being utilized. The baseline may be changing in the mod- eling process. There is a need to evaluate radically differ- Other speakers have highlighted many of the issues that ent scenarios. There is also a need to be able to quickly need to be addressed as we work toward improving both accommodate changing baselines. travel demand models and the use of new modeling tech- There are a number of transportation planning issues niques. Examples of model enhancements include and questions that cannot be addressed by current travel addressing future land use changes, activity and travel forecasting models. There are a range of questions stem- budgets, and departure time and peak spreading. Being ming from opportunities related to technology, institu- able to assess traffic operations impacts, including traffic tional change, and broader social and environmental control and queuing, is also important. change that challenge the capabilities and the range of A number of factors appear to be influencing the slow predictive powers of models currently being used or envi- movement toward widespread application of new travel sioned in the future. I think this is an issue that needs to demand models. There is a perceived lack of need in be addressed in the long term. many areas due to institutional issues and market iner- To help address this issue and other concerns, the tia. There is sometimes a lack of interest in using models travel modeling community needs a comprehensive and beyond meeting federal and state requirements. There coherent view of the range of demands being placed on are limited data on the benefits of using new models. travel models. This approach means establishing a top- There is limited quality assurance and quality control on down process that begins by inventorying capabilities, some travel demand models. Finally, many MPOs and identifying needs and potential needs, and moving areas face staffing and financial limitations. toward a balanced research and application perspective. There are also factors pushing for change, however. To help bridge the gap between current model practice First, there is more stress on the policy and investment and innovative model research, the travel modeling com- decision process in many areas. The growth in demand munity should establish a program to further identify for travel in all sectors is outpacing the growth in supply. development and deployment goals. Research, demon- Active, well-informed stakeholders with competing stration projects, and funding should be tied to a agendas are pushing for better data and better models. consensus-driven program that represents the best assess- Policy makers and all groups are faced with more com- ment of methods to address future forecasting needs. plex decisions. There is a need to increase resolution and focus on spe- Let me suggest a few areas on which we should focus cific time-of-day models. Other areas of need include the our energy and resources. First, there is a need for accu- ability to forecast turning movements, evacuation plan- rate data programs to support the "3C" planning ning, transportation demand management analysis, and process. We must understand key regional travel markets congestion management. Enhanced capabilities in trans- and support best-practice model validation. Second, it is portation system management and intelligent transporta- important to improve model quality assurance and qual- tion system deployment and evaluation are also needed. ity control methodologies. Third, we need to make the Safety planning, submode analysis, and interim improve- results from the travel demand modeling process more ment planning and analysis highlight other needs. useful and understandable to policy makers and stake- It is important that travel modeling focuses on more holders. Finally, we must do a better job of incubating than just transportation. The framework of analysis is new travel demand modeling technologies and methods. becoming increasingly comprehensive and travel models To help advance the state of the practice, we need to are being asked to predict travel impacts on the entire improve access to new tools through licensing, distribu- social fabric. Examples of these expanded social issues tion, teaching, and research. Practical documentation of include environmental justice; land use economics and the new travel demand forecasting tools and techniques is location; urban planning; system operations policy; and also needed. Case studies using real issues and real data, air, noise, and water quality. as well as published peer review findings, are required. We also face increasing complexity in understanding needoption relationships. Markets are more complex Bruce Spear, Federal Highway Administration, moder- with diverse supplydemand relationships. There is ated this session.