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Model 8 covers stops and trip mode choice. This model determines whether any stops are made on either the outbound (from home), or inbound leg of the tour and the location of those stops. Furthermore, given the overall tour mode previously determined, the exact mode the traveler uses for each segment or trip on the tour is determined on the basis of a set of rules. Each of these trips is connected, and all stops are based upon the pre- vious choices. Therefore, if the main tour mode is tran- sit, then a person will not be able to choose to drive alone for a lunch trip made at work. Furthermore, if the pri- mary mode of a tour is by automobile, then a person would be allowed to drop off a child at school and then drive to work. The final trips are then aggregated by zones and assigned as conventional trip tables to the highway and transit networks. The core choice models (Models 1 through 8 as described above) are applied in a disaggregate manner. Instead of using aggregate fractional probabilities to esti- mate the number of trips, the new model is applied by microsimulation of each individual household, person, or tour, mostly using Monte Carlo realization of each possibility estimated by the models, with use of a ran- dom number series to determine which possibility is cho- sen for that record. Both the population synthesizer and the automobile ownership models, however, perform the microsimulation through a deterministic discretizing procedure that avoids Monte Carlo variability. The new model is applied with an implementation of three global feedback loops for consistency between highway travel times that are both used as inputs to, and as forecast out- puts of, the model. The new model is being used by MORPC for confor- mity analysis, transit alternative analysis, and highway- related management information systems projects in the Columbus region. It is being used to generate forecasts for the North Corridor Transit Project (NCTP), currently in the draft environmental impact statement stage, with a potential New Starts submittal within the next few years. The NCTP is analyzing various travel modes along a 13- mi corridor that includes three major employment centersâ the Central Business District, Ohio State Uni- versity, and the CrosswoodsâPolaris areaâ interspersed with large residential areas. 32 INNOVATIONS IN TRAVEL DEMAND MODELING, VOLUME 2