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THE SECRET IS IN THE SEGUE 55 documentation. There is also an issue with the lack of Working with stakeholders is an ongoing priority. full integration of transit and highway networks. LION Involving stakeholders in defining the model needs and is used in New York City, while TIGER is used in other applications is important. It is also important to involve parts of the region. The lack of integration of land use stakeholders in the model calibration and validation models and proper feedback to NYBPM is another issue. processes and in the discussion of model usage and There is a land use model, but it is not yet integrated into improvements. Gaining consensus on the definition of the NYBPM. Also, the processing time for the NYPBM the zonal system, the survey design, and the forecasts is very long. Initially it was taking up to 7 days to run the and calibration results was also accomplished by work- model. The computer processing time alone has been ing with stakeholders. It took time to reach an agree- reduced to approximately 4 days. A current project is ment on the socioeconomic and demographic data at the examining approaches to reduce this time further. county level. The modeling environment also presents chal- A number of model improvements are planned and lenges. These challenges include the diversity of the large a new wave of data collection is scheduled for in 2007. region, software issues, and hardware issues. The region These efforts include a household travel survey, an air- encompasses almost 10,000 square miles. There is also port survey, a taxi survey, and a work place survey. Tran- diversity in the size, population, and employment of each sit origindestination surveys and bridge and tunnel zone, as well as variation of available modes and con- origindestination surveys are also planned. Other nections. There is variation in the travel behavior and efforts include a cordon survey, a travel time survey, and travel patterns of different population subgroups and traffic counts and occupancy surveys. The results from there is a large group of temporary workers who are con- these surveys will be used to update the NYBPM. tinually on the move. The travel behavior of people in In addition to incorporating the results of the new New Jersey is very different from that of people in New surveys, other planned activities include improving the York. The term "Manhattan Syndrome" is used for highway-transit connection, improving transit models, unexplained travel behavior. and integrating NYBPM with the land use model. Possi- The software issues include changes in TransCAD ble web applications are being explored, including pro- and the compatibility of various software packages. The viding model output analysis capabilities and model run NYBPM was developed using TransCAD 4.0. The capabilities for more of a distributed process. A plan has NYBPM modules are not compatible with the newer ver- also been made to provide improved flowchart-based, sion of TransCAD. An ongoing challenge has been that online help and documentation. More project applica- users have different versions of TransCAD. Some users tions in the region are anticipated. The NYBPM user's have experienced difficulties in running the model group support will continue to meet every 2 months to because of this problem. help with these improvements. One hardware issue relates to data storage needs. With nearly 9 million households in the base year, the journey production files are over 500 megabytes. The USING ACTIVITY-BASED MODELS FOR mode destination choice model processes over 25 million POLICY DECISION MAKING paired journeys by eight trip purposes. The output files are over 300 megabytes. There are six highway classes Erik Sabina and Thomas Rossi and four transit trip tables for each of the four time peri- ods. The combined file size is approximately 2.5 Erik Sabina discussed the development of a new activity- gigabytes. based travel forecasting model for the Denver metropol- There is an ongoing need to provide training to itan area by the Denver Regional Council of various stakeholders and users. A 1-day training course Governments (DRCOG). He described the planning is provided for decision makers. A 3- to 5-day training process in the Denver area and the proposed activity- course is available for individuals with some modeling based model. Volume 2 includes a paper on the topic.2 background. Hands-on training, spanning several weeks, The following points were covered in his presentation. is provided for staff of member agencies who will be using the model for specific projects. These training A number of factors influenced consideration of a courses focus on the purpose and use of the activity- new activity-based travel forecasting model for the Den- based models and the specific use of the NYBPM. Staff ver area, including the Integrated Regional Model (IRM) from other agencies can also use the NYMTC's com- vision phase conducted by DRCOG, the new Colorado puter facilities. The lack of trained and experienced mod- Tolling Enterprise (CTE) within the Colorado Depart- eling staff at many agencies is an ongoing challenge. Many public agencies experience high staff turnover 2See Sabina, E., and T. Rossi. Using Activity-Based Models for Policy rates. Decision Making. Volume 2, pp. 177180.