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each scenario. The trip distribution and mode choice stages are more closely intertwined with the new microsimulation models. In theory, the new models offer additional possibilities for quantifying user benefits of transit projects compared with the traditional models. There are still numerous methodological and technical questions to be addressed, however. ⢠The MORPC model was used in the North Corri- dor study. Key subsets of the model include the primary tour destination model, the time- of- day model, the entire tour mode and best transit submode, the stop frequency model, the stop location model, the trip mode model, and the traffic and transit assignment. ⢠In the North Corridor study, the MORPC model was first run for the base scenario. All tours were fixed with their primary destinations and the build scenario was run for several iterations, including only mode, stop frequency, and stop location choices, as well as assign- ments. The tour- level mode choice statistics are used for the user benefit calculation. The SFCTA model has also been used on an FTA New Starts program analysis. This assessment was part of the New Central Subway Project in downtown San Francisco. With the SFCTA model, user benefits are estimated from both the entire tour mode choice and the trip mode choice. APPLICATION OF THE MID- OHIO REGIONAL PLANNING COMMISSION MICROSIMULATION MODEL: REVIEW OF THE NEW STARTS PROGRAM David Schmitt Dave Schmitt described the use of the MORPC microsim- ulation model to generate forecasts for the North Corri- dor Transit Project (NCTP). He summarized the model elements, the requirements of the FTA New Starts pro- gram, the NCTP, and the application of the model with the NCTP. Volume 2 includes a paper on this topic.6 The following points were covered in his presentation. ⢠An independent review of the MORPC microsimu- lation model was conducted at a New Starts level of scrutiny. The key review elements included trip distribu- tion, transit network (including access coding, automo- bile and transit speeds, path building, and mode choice), transit assignment, and user benefit results. ⢠The MORCP model is a disaggregate tour- based model applied with the microsimulation of each individ- ual household, person, or tour. Travel is accounted for at the tour level, as opposed to the trip level, for each indi- vidual household and person, rather than zonal and mar- ket segment aggregates. The network and assignment procedures use disaggregate tours converted to trips and aggregated to the zonal level. The model uses a typical zonal network, which includes 1,877 zones and 26,000 links, with transit and path building and assignment rou- tines in TP+. ⢠The New Starts program is the primary federal fund- ing source for new fixed- guideway capital investments. Approximately $1.5 billion is available for fixed- guideway transit investments on an annual basis. All proj - ects undergo an evaluation and are rated by FTA. A key criterion in the evaluation is the cost per unit of benefit. The cost measure is the annualized incremental capital cost plus the annual operating cost. The benefit measure is the hours of transportation system user benefits. Since 2002, the characteristics of the travel forecasting model used in the analysis have become a concern to FTA. The travel demand model used in a New Starts analysis must undergo rigorous scrutiny in terms of model structure, parameter values, and forecasting results. ⢠The North Corridor included in the New Starts proj - ect is 13 miles in length. The NCTP is currently in the Draft Environmental Impact Statement stage, with potential sub- mission as a New Starts project in the next few years. The corridor includes three major employment centers inter- spersed with large residential areas. The three employment centers are the Crosswoods/Polaris area, Ohio State Uni- versity, and the Columbus CBD. A total of 13 districts were used in the analysis. ⢠The simulated year 2000 work trip distribution was compared with the 2000 Census Transportation Planning Package (CTPP) to assess the work- tour com- ponent of the distribution model. Overall, the modeled work trip distribution appeared to be reasonable and almost all the markets were within 20% of the CTPP total. The modeled trip distribution for all journeys and tours compared with the CTPP was not as good as the work- tour distribution, but was still reasonable. A few production districts overestimated trips, while the attrac- tion districts appeared closer to the CTPP. ⢠User benefit results are considered reasonable if they reflect the benefits of the proposed build project. For example, the corridor area should accrue the major- ity of user benefits, while areas outside of the corridor should receive minimal benefits. Major employment areas that benefit the most from the project should receive larger user benefits. The district- to- district sum- mary tables and corresponding maps illustrating the travel analysis zones that receive the most benefits and disbenefits from the project were reviewed. This approach is useful in evaluating whether the user benefit results are directly related to the proposed project. 18 INNOVATIONS IN TRAVEL DEMAND MODELING, VOLUME 1 6 See Schmitt, D. Application of the Mid- Ohio Regional Planning Commission Microsimulation Model: Review of the New Starts Program. Volume 2, pp. 37â45.
