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From page 371... ... J-1 A p p e n d i x J Model Implementation and Calibration Contents J-1 Overview J-2 Existing Salt Lake City Models J-5 Incorporating Transit Amenities and Service Characteristics J-6 Transit Mode Definition and Path-Finding J-9 Transit Mode Choice Utility Expressions J-11 Transit Path Choice Model Calibration J-13 Comparative Results Overview The purpose of the model implementation and calibration was to apply the scaled marginal rates of substitution or values in equivalent minutes of in-vehicle travel time (presented in the previous section) in a standard practice travel model and modify the mode choice model structure to recognize path choices rather than technology mode choices.The estimated values of non-traditional transit service attributes from the MaxDiff models were incorporated into an existing travel model's transit path-building and mode choice components to demonstrate their applicability in practice. Read the entire page →
From page 372... ... J-2 Characteristics of Premium Transit Services that Affect Choice of Mode SLC: Salt Lake City FIGURE J-1. Regional overview of transit system in Salt Lake City. Read the entire page →
From page 373... ... Model Implementation and Calibration J-3 local bus, express bus, BRT, LRT, and commuter rail -- by each of the two access types (walk and drive) Read the entire page →
From page 374... ... J-4 Characteristics of premium Transit Services that Affect Choice of Mode The mode choice model has been estimated separately for four trip purposes: (1) homebased work (HBW) Read the entire page →
From page 375... ... Model implementation and Calibration J-5 For the purpose of this project, the current mode choice model was recalibrated to a more recent transit on-board survey. The transit survey was conducted system-wide (including all the five transit modes) Read the entire page →
From page 376... ... J-6 Characteristics of premium Transit Services that Affect Choice of Mode the existing model. Hence, the values of attributes that were available were scaled by each bundle of premium attributes to reflect the full benefit that could potentially be gained from premium transit characteristics. Read the entire page →
From page 377... ... Model implementation and Calibration J-7 Bundled Aribute Premium Service Aribute CRT LRT LOCAL EXP BRT Value (min. Read the entire page →
From page 378... ... J-8 Characteristics of Premium Transit Services that Affect Choice of Mode TABLE J-6. Path-building parameters for the transit path choice model. Read the entire page →
From page 379... ... Model implementation and Calibration J-9 An issue of interest prior to implementing the transit path and mode choice model was to assess the number of "unique" paths that were being produced as a result of the modified pathgenerating process. Given that an overlap in paths implies a possible correlation among the attributes of the path choices, this may lead to the violation of the independence of irrelevant alternative (IIA) Read the entire page →
From page 380... ... J-10 Characteristics of premium Transit Services that Affect Choice of Mode needed. The number of boardings by mode for each transit path was calculated during the process of identifying and removing duplicate paths. Read the entire page →
From page 381... ... Model implementation and Calibration J-11 TABLE J-8. Age segmentation in transit path choice model. Read the entire page →
From page 382... ... J-12 Characteristics of premium Transit Services that Affect Choice of Mode The calibration primarily involved adjusting overall transit constant. The number of transit paths built changed from 10 in the existing model to six in the transit path choice model. Read the entire page →
From page 383... ... Model implementation and Calibration J-13 It should be noted here that because this is a research effort a full-scale recalibration of the model was not attempted. The focus was more on matching transit trips by mode and transit trips by purpose (i.e., marginal distributions) Read the entire page →
From page 384... ... J-14 Characteristics of premium Transit Services that Affect Choice of Mode TABLE J-12. Comparison of linked transit trips by access and detailed mode. Read the entire page →
From page 385... ... Model implementation and Calibration J-15 TABLE J-13. Comparison of transit boardings by route group. Read the entire page →
From page 386... ... J-16 Characteristics of premium Transit Services that Affect Choice of Mode TABLE J-14. Path benefits (IVTT minutes) Read the entire page →
From page 387... ... Model implementation and Calibration J-17 transit path. The coefficient of the transfer penalty has been converted to equivalent IVTT minutes by dividing it by IVTT coefficient. Read the entire page →
From page 388... ... J-18 Characteristics of premium Transit Services that Affect Choice of Mode In more complex paths (involving two or more services) , the total effects in the existing model are positive because of the hierarchical nature of the transit paths. Read the entire page →
From page 389... ... Abbreviations and acronyms used without deﬁnitions in TRB publications: A4A Airlines for America AAAE American Association of Airport Executives AASHO American Association of State Highway Officials AASHTO American Association of State Highway and Transportation Officials ACI–NA Airports Council International–North America ACRP Airport Cooperative Research Program ADA Americans with Disabilities Act APTA American Public Transportation Association ASCE American Society of Civil Engineers ASME American Society of Mechanical Engineers ASTM American Society for Testing and Materials ATA American Trucking Associations CTAA Community Transportation Association of America CTBSSP Commercial Truck and Bus Safety Synthesis Program DHS Department of Homeland Security DOE Department of Energy EPA Environmental Protection Agency FAA Federal Aviation Administration FHWA Federal Highway Administration FMCSA Federal Motor Carrier Safety Administration FRA Federal Railroad Administration FTA Federal Transit Administration HMCRP Hazardous Materials Cooperative Research Program IEEE Institute of Electrical and Electronics Engineers ISTEA Intermodal Surface Transportation Efficiency Act of 1991 ITE Institute of Transportation Engineers MAP-21 Moving Ahead for Progress in the 21st Century Act (2012) NASA National Aeronautics and Space Administration NASAO National Association of State Aviation Officials NCFRP National Cooperative Freight Research Program NCHRP National Cooperative Highway Research Program NHTSA National Highway Traffic Safety Administration NTSB National Transportation Safety Board PHMSA Pipeline and Hazardous Materials Safety Administration RITA Research and Innovative Technology Administration SAE Society of Automotive Engineers SAFETEA-LU Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (2005) Read the entire page →

From page 371...

... J-1 A p p e n d i x J Model Implementation and Calibration Contents J-1 Overview J-2 Existing Salt Lake City Models J-5 Incorporating Transit Amenities and Service Characteristics J-6 Transit Mode Definition and Path-Finding J-9 Transit Mode Choice Utility Expressions J-11 Transit Path Choice Model Calibration J-13 Comparative Results Overview The purpose of the model implementation and calibration was to apply the scaled marginal rates of substitution or values in equivalent minutes of in-vehicle travel time (presented in the previous section) in a standard practice travel model and modify the mode choice model structure to recognize path choices rather than technology mode choices.The estimated values of non-traditional transit service attributes from the MaxDiff models were incorporated into an existing travel model's transit path-building and mode choice components to demonstrate their applicability in practice.