The San Francisco County Chained Activity Modeling Process (SF-CHAMP) was developed for the San F... more The San Francisco County Chained Activity Modeling Process (SF-CHAMP) was developed for the San Francisco County Transportation Authority (SFCTA) to provide detailed forecasts of travel demand for various planning applications. These applications included developing countywide plans, providing input to microsimulation modeling for corridor and project-level evaluations, transit planning, and neighborhood planning. The objective was to represent accurately the complexity of the destination and the temporal and modal options and to provide detailed information on travelers making discrete choices. These objectives led to the development of a tour-based model that uses synthesized population as the basis for decision making rather than zonal-level aggregate data sources. Most of the tour-based model’s nine components were estimated by means of household survey data for San Francisco, California, residents only that were collected by the Metropolitan Transportation Commission (MTC). Eac...
The motivation is to synthesize existing research and package it into an easy to use software too... more The motivation is to synthesize existing research and package it into an easy to use software tool that can be used by transportation and land use planners. The innovation in the project is that by combining multiple research sources, we are able to provide more comprehensive software that bridges the gap between regional agencies visioning processes and their transportation plans, which evaluate projects. This tool evaluates scenarios at a regional level with available data sources.
A bi-lateral trading game is developed as the core component of the supplier selection mechanism ... more A bi-lateral trading game is developed as the core component of the supplier selection mechanism of the Chicao meso-scale freight model. In the procurement market game (PMG), agents representing producers of an output commodity (“buyers”) are instantiated with a quantity of an input commodity to purchase and a set of preference weights that allow them to tradeoff unit costs, service time, and potentially other attributes when considering the utility of a potential trading partner. Buyers are also endowed with “attitudes” towards risk, such as the maximum proportion of units to be purchased from any one source. Agents representing suppliers of the commodity to be traded (“sellers”) are instantiated with an annual production capacity and unit costs. The primary objective of sellers is to capture as much revenue as possible from buyers, up to their capacity limit. Because both buyers and sellers are situated geographically, transportation and logistics costs and shipping times are a fu...
The Strategic Highway Research Program 2 (SHRP 2) program developed proof-of-concept Dynamic Inte... more The Strategic Highway Research Program 2 (SHRP 2) program developed proof-of-concept Dynamic Integrated Models in partnership with planning organizations in Sacramento, California, and Jacksonville, Florida. “Dynamic Integrated Model” refers to an activity-based travel demand model linked with a feedback loop to a Dynamic Traffic Assignment (simulation) model. The goal of that research was to improve urban-scale modeling and network procedures to address operations or spot improvements that affect travel-time choice, route choice, mode choice, reliability, or emissions. Building a new activity-based model set for transportation planning is an expensive and time-consuming commitment. The objective of this research was to determine if activity-based model parameters can be successfully transferred from one community to another. If transfer of parameters could be shown to produce reasonable results, it could save development time and money. DaySim, an activity-based travel demand model originally developed in Sacramento, California, was applied to Jacksonville, Florida, with Sacramento parameters and then calibrated to the Jacksonville environment. DaySim was also applied to Tampa, Florida, with Sacramento parameters and then calibrated with local data. A statistical analysis was performed to identify significant differences between transferred parameters and parameters developed from local data. Variations in model performance on validation tests were also evaluated. The analyses identified specific model components that would be better transferred than re-estimated and others for which it would be better to re-estimate. A model with borrowed parameters must still be calibrated against local conditions. A significant finding of the research was that there must be a good match between the complexity of the source model to be transferred and the depth and coverage of data available for calibrating at the destination site. A second finding was that urban areas must be similar in key demographics such as household size, age, income, auto ownership, and trip purposes. This report will be of particular interest to planning organizations considering development of an activity-based travel demand model and, in general, to professionals who use travel demand models as part of the transportation planning process.
Most current travel demand forecasting models are not sufficiently sensitive to the dynamic inter... more Most current travel demand forecasting models are not sufficiently sensitive to the dynamic interplay between travel behavior and network conditions by detailed time-of-day, and as a result are unable to reasonably represent the effects of transportation policies such as variable road pricing and travel demand management strategies. The SHRP 2 C10A project was initiated in order to make operational a dynamic integrated model system that realistically captures the complex interplay between demand and supply in order to provide more reasonable representations of the effects of transportation policies. This paper documents the preliminary results and qualitative interpretation of a set of systematic sensitivity tests of the model’s enhanced temporal and spatial structure and policy capabilities. The sensitivity tests described in this paper cover a broad range of policy options including pricing, travel demand management, and operational strategies that were evaluated using the Burlington implementation of the model system. The model system demonstrated sensitivities to the pricing and travel demand management strategies that appeared reasonable in terms of the direction and magnitude of change at both aggregate and disaggregate temporal and spatial resolutions. However, the model system sensitivities to the operational improvements, specifically signal progression along three key regional corridors, were not as robust or conclusive.
Transportation Research Record: Journal of the Transportation Research Board, 2016
This paper describes a model system designed and implemented to simulate long-distance travel for... more This paper describes a model system designed and implemented to simulate long-distance travel for all U.S. households. The model system was created in the final phase of FHWA research project Foundational Knowledge to Support a Long-Distance Passenger Travel Demand Modeling Framework. It is a tour-based system simulating individual tours for individual households from a synthetic population. The models are disaggregate models of auto ownership, tour generation, tour duration, travel party size, tour destination choice, and tour mode choice. The model system runs in 1 to 2 h on a standard PC, simulating a full year’s long-distance tours for the entire U.S. population. The paper describes the model structure, input data, and software implementation and provides some results from the initial model calibration, validation, highway assignment, and sensitivity tests.
Intercity travel is rising in importance in the U.S. with many states and the federal government ... more Intercity travel is rising in importance in the U.S. with many states and the federal government faced with improving mobility and reducing impacts for these travelers. The Federal Highway Administration (FHWA) has invested in several studies to better understand intercity travel; this study is an extension of that interest, focused on exploratory research to develop a long distance passenger travel demand model framework. The modeling framework is a tour-based micro-simulation model of annual long distance passenger travel for all households in the U.S. The models schedule travel across a full year to capture business travel (conferences, meetings and combined business/leisure) and leisure travel (visiting friends and family, personal business and shopping, relaxation, sight-seeing, outdoor recreation, and entertainment). The models are multimodal (auto, rail, bus, and air) based on national networks for each mode to provide opportunities for evaluation of intercity transportation investments or testing national policies for economic, environmental and pricing. Advanced modeling methods were tested for the scheduling, time use, activity participation and joint mode and destination models, including multiple discrete-continuous extreme value (MDCEV) for the scheduling models and cross nested logit choice for the joint mode and destination models. The modeling framework was demonstrated, with application software that simulate long distance travel for all U.S. households. This paper is a high-level overview of the exploratory research over 3 years.
In a recent forum on road pricing, attendees discussed limitations with current travel demand for... more In a recent forum on road pricing, attendees discussed limitations with current travel demand forecasting approaches for pricing studies. In addition, Cambridge Systematics, Inc. (CS) recently completed a paper on the limitations of studies used to advance toll projects and on the opinions of Washington State’s community leaders. Based on these sources and recent experience in developing forecasting models for toll projects, the authors have identified the following issues as important to improving existing travel models for pricing studies: inaccurate values of time for specific travelers, trip purposes, modes, and time periods; and lack of temporal detail and behavioral choice for time-of-day models. CS’s approach to advance travel models for pricing studies focuses on these issues as the most critical to be addressed in existing models. The authors have been involved in the development and application of these methods for trip-based models in Minnesota and Washington, as well as for activity-based models in San Francisco. This paper describes innovative methods to incorporate advances to address these issues. In addition, the authors describe strategies to optimize tolls for pricing studies. Finally, more research is proposed to address additional limitations of existing models.
Transportation Research Record: Journal of the Transportation Research Board, 2003
The San Francisco Bay Area Water Transit Authority is evaluating expanded ferry service, as requi... more The San Francisco Bay Area Water Transit Authority is evaluating expanded ferry service, as required by the California Legislature. As part of this process, Cambridge Systematics developed forecasts using a combination of market research strategies and the addition of nontraditional variables into the mode choice modeling process. The focus of this work was on expanding the mode choice model to recognize travelers' attitudes and different market segments. Structural equation modeling was used to simultaneously identify the attitudes of travel behaviors and the causal relationships between traveler's socioeconomic profile and traveler attitudes. Six attitudinal factors were extracted, and three of these were used to partition the ferry-riding market into eight segments. These market segments were used to estimate stated preference mode choice models for 14 alternative modes, which separated the travelers' reactions to time savings by market segment and which recognized th...
... Spitz e-mail: gspitz@rsginc.com J. Lobb e-mail: jlobb@rsginc.com M. Campbell e-mail: mcampbel... more ... Spitz e-mail: gspitz@rsginc.com J. Lobb e-mail: jlobb@rsginc.com M. Campbell e-mail: mcampbell@rsginc.com B. Sana e-mail ... users (had not used transit in past 12 months), they were asked about their familiarity with the transit schedules, routes available, fare payment options ...
Transportation Research Record: Journal of the Transportation Research Board, 2004
The San Francisco Bay Area Water Transit Authority is evaluating expanded ferry service, as requi... more The San Francisco Bay Area Water Transit Authority is evaluating expanded ferry service, as required by the California legislature. Predicting ferry ridership has historically been difficult because water-transit riders often choose their travel mode based on factors other than travel time and cost. Most forecast models place a premium on time and cost and ignore other traveler attitudes. Structural equation modeling was used to identify simultaneously travel behavior and the causal relationships between a traveler's socioeconomic profile and travel attitudes. These market segments were used to estimate stated-preference (SP) mode choice models for 14 alternative modes, which separated the traveler's reaction to time savings by market segment and recognized that modal choices were different for market segments that were sensitive to travel stress or a desire to help the environment. The focus was on the application of the model to evaluate three future-year alternatives and ...
Transportation Research Record: Journal of the Transportation Research Board, 2002
Results of a design process for new integrated land use and transportation models recently comple... more Results of a design process for new integrated land use and transportation models recently completed for the Puget Sound Regional Council (PSRC) are presented. The design process, which began with an analysis of policy requirements and assessment of the current models in use at PSRC and nationally, employed an iterative and participatory approach to ensure that model requirements were clearly identified and that the proposed model design would address those requirements. Development of the model requirements drew on a broad survey of the literature and of operational models; the proposed model design offers a unique approach to the development of a new land use and travel model system that corresponds to a behavioral integration of the choice processes across relevant time frames.
Transportation Research Record: Journal of the Transportation Research Board, 1998
As the demand for using park-and-ride lots grows, the need to accurately forecast these trips als... more As the demand for using park-and-ride lots grows, the need to accurately forecast these trips also grows. Initially, demand for park-and-ride lots was forecast using a technique that identified the draw area for each lot and estimated demand without regard to capacity. These were simplifying assumptions that are no longer appropriate with respect to current demand for park-and-ride lots. In King County, Washington, the 12 largest park-and-ride lots are currently operating at 95 percent utilization. According to a recent park-and-ride lot survey in King County, there is significant latent demand for using lots that are full. The analysis of demand for parking in park-and-ride lots in King County was developed as part of the Washington State Department of Transportation Public/Private Partnership Program for the Park-and-Ride Capacity Enhancement Project. There were 17 park-and-ride lots considered for capacity enhancement. The approach to evaluate park-and-ride lot demand uses a tech...
The San Francisco County Chained Activity Modeling Process (SF-CHAMP) was developed for the San F... more The San Francisco County Chained Activity Modeling Process (SF-CHAMP) was developed for the San Francisco County Transportation Authority (SFCTA) to provide detailed forecasts of travel demand for various planning applications. These applications included developing countywide plans, providing input to microsimulation modeling for corridor and project-level evaluations, transit planning, and neighborhood planning. The objective was to represent accurately the complexity of the destination and the temporal and modal options and to provide detailed information on travelers making discrete choices. These objectives led to the development of a tour-based model that uses synthesized population as the basis for decision making rather than zonal-level aggregate data sources. Most of the tour-based model’s nine components were estimated by means of household survey data for San Francisco, California, residents only that were collected by the Metropolitan Transportation Commission (MTC). Eac...
The motivation is to synthesize existing research and package it into an easy to use software too... more The motivation is to synthesize existing research and package it into an easy to use software tool that can be used by transportation and land use planners. The innovation in the project is that by combining multiple research sources, we are able to provide more comprehensive software that bridges the gap between regional agencies visioning processes and their transportation plans, which evaluate projects. This tool evaluates scenarios at a regional level with available data sources.
A bi-lateral trading game is developed as the core component of the supplier selection mechanism ... more A bi-lateral trading game is developed as the core component of the supplier selection mechanism of the Chicao meso-scale freight model. In the procurement market game (PMG), agents representing producers of an output commodity (“buyers”) are instantiated with a quantity of an input commodity to purchase and a set of preference weights that allow them to tradeoff unit costs, service time, and potentially other attributes when considering the utility of a potential trading partner. Buyers are also endowed with “attitudes” towards risk, such as the maximum proportion of units to be purchased from any one source. Agents representing suppliers of the commodity to be traded (“sellers”) are instantiated with an annual production capacity and unit costs. The primary objective of sellers is to capture as much revenue as possible from buyers, up to their capacity limit. Because both buyers and sellers are situated geographically, transportation and logistics costs and shipping times are a fu...
The Strategic Highway Research Program 2 (SHRP 2) program developed proof-of-concept Dynamic Inte... more The Strategic Highway Research Program 2 (SHRP 2) program developed proof-of-concept Dynamic Integrated Models in partnership with planning organizations in Sacramento, California, and Jacksonville, Florida. “Dynamic Integrated Model” refers to an activity-based travel demand model linked with a feedback loop to a Dynamic Traffic Assignment (simulation) model. The goal of that research was to improve urban-scale modeling and network procedures to address operations or spot improvements that affect travel-time choice, route choice, mode choice, reliability, or emissions. Building a new activity-based model set for transportation planning is an expensive and time-consuming commitment. The objective of this research was to determine if activity-based model parameters can be successfully transferred from one community to another. If transfer of parameters could be shown to produce reasonable results, it could save development time and money. DaySim, an activity-based travel demand model originally developed in Sacramento, California, was applied to Jacksonville, Florida, with Sacramento parameters and then calibrated to the Jacksonville environment. DaySim was also applied to Tampa, Florida, with Sacramento parameters and then calibrated with local data. A statistical analysis was performed to identify significant differences between transferred parameters and parameters developed from local data. Variations in model performance on validation tests were also evaluated. The analyses identified specific model components that would be better transferred than re-estimated and others for which it would be better to re-estimate. A model with borrowed parameters must still be calibrated against local conditions. A significant finding of the research was that there must be a good match between the complexity of the source model to be transferred and the depth and coverage of data available for calibrating at the destination site. A second finding was that urban areas must be similar in key demographics such as household size, age, income, auto ownership, and trip purposes. This report will be of particular interest to planning organizations considering development of an activity-based travel demand model and, in general, to professionals who use travel demand models as part of the transportation planning process.
Most current travel demand forecasting models are not sufficiently sensitive to the dynamic inter... more Most current travel demand forecasting models are not sufficiently sensitive to the dynamic interplay between travel behavior and network conditions by detailed time-of-day, and as a result are unable to reasonably represent the effects of transportation policies such as variable road pricing and travel demand management strategies. The SHRP 2 C10A project was initiated in order to make operational a dynamic integrated model system that realistically captures the complex interplay between demand and supply in order to provide more reasonable representations of the effects of transportation policies. This paper documents the preliminary results and qualitative interpretation of a set of systematic sensitivity tests of the model’s enhanced temporal and spatial structure and policy capabilities. The sensitivity tests described in this paper cover a broad range of policy options including pricing, travel demand management, and operational strategies that were evaluated using the Burlington implementation of the model system. The model system demonstrated sensitivities to the pricing and travel demand management strategies that appeared reasonable in terms of the direction and magnitude of change at both aggregate and disaggregate temporal and spatial resolutions. However, the model system sensitivities to the operational improvements, specifically signal progression along three key regional corridors, were not as robust or conclusive.
Transportation Research Record: Journal of the Transportation Research Board, 2016
This paper describes a model system designed and implemented to simulate long-distance travel for... more This paper describes a model system designed and implemented to simulate long-distance travel for all U.S. households. The model system was created in the final phase of FHWA research project Foundational Knowledge to Support a Long-Distance Passenger Travel Demand Modeling Framework. It is a tour-based system simulating individual tours for individual households from a synthetic population. The models are disaggregate models of auto ownership, tour generation, tour duration, travel party size, tour destination choice, and tour mode choice. The model system runs in 1 to 2 h on a standard PC, simulating a full year’s long-distance tours for the entire U.S. population. The paper describes the model structure, input data, and software implementation and provides some results from the initial model calibration, validation, highway assignment, and sensitivity tests.
Intercity travel is rising in importance in the U.S. with many states and the federal government ... more Intercity travel is rising in importance in the U.S. with many states and the federal government faced with improving mobility and reducing impacts for these travelers. The Federal Highway Administration (FHWA) has invested in several studies to better understand intercity travel; this study is an extension of that interest, focused on exploratory research to develop a long distance passenger travel demand model framework. The modeling framework is a tour-based micro-simulation model of annual long distance passenger travel for all households in the U.S. The models schedule travel across a full year to capture business travel (conferences, meetings and combined business/leisure) and leisure travel (visiting friends and family, personal business and shopping, relaxation, sight-seeing, outdoor recreation, and entertainment). The models are multimodal (auto, rail, bus, and air) based on national networks for each mode to provide opportunities for evaluation of intercity transportation investments or testing national policies for economic, environmental and pricing. Advanced modeling methods were tested for the scheduling, time use, activity participation and joint mode and destination models, including multiple discrete-continuous extreme value (MDCEV) for the scheduling models and cross nested logit choice for the joint mode and destination models. The modeling framework was demonstrated, with application software that simulate long distance travel for all U.S. households. This paper is a high-level overview of the exploratory research over 3 years.
In a recent forum on road pricing, attendees discussed limitations with current travel demand for... more In a recent forum on road pricing, attendees discussed limitations with current travel demand forecasting approaches for pricing studies. In addition, Cambridge Systematics, Inc. (CS) recently completed a paper on the limitations of studies used to advance toll projects and on the opinions of Washington State’s community leaders. Based on these sources and recent experience in developing forecasting models for toll projects, the authors have identified the following issues as important to improving existing travel models for pricing studies: inaccurate values of time for specific travelers, trip purposes, modes, and time periods; and lack of temporal detail and behavioral choice for time-of-day models. CS’s approach to advance travel models for pricing studies focuses on these issues as the most critical to be addressed in existing models. The authors have been involved in the development and application of these methods for trip-based models in Minnesota and Washington, as well as for activity-based models in San Francisco. This paper describes innovative methods to incorporate advances to address these issues. In addition, the authors describe strategies to optimize tolls for pricing studies. Finally, more research is proposed to address additional limitations of existing models.
Transportation Research Record: Journal of the Transportation Research Board, 2003
The San Francisco Bay Area Water Transit Authority is evaluating expanded ferry service, as requi... more The San Francisco Bay Area Water Transit Authority is evaluating expanded ferry service, as required by the California Legislature. As part of this process, Cambridge Systematics developed forecasts using a combination of market research strategies and the addition of nontraditional variables into the mode choice modeling process. The focus of this work was on expanding the mode choice model to recognize travelers' attitudes and different market segments. Structural equation modeling was used to simultaneously identify the attitudes of travel behaviors and the causal relationships between traveler's socioeconomic profile and traveler attitudes. Six attitudinal factors were extracted, and three of these were used to partition the ferry-riding market into eight segments. These market segments were used to estimate stated preference mode choice models for 14 alternative modes, which separated the travelers' reactions to time savings by market segment and which recognized th...
... Spitz e-mail: gspitz@rsginc.com J. Lobb e-mail: jlobb@rsginc.com M. Campbell e-mail: mcampbel... more ... Spitz e-mail: gspitz@rsginc.com J. Lobb e-mail: jlobb@rsginc.com M. Campbell e-mail: mcampbell@rsginc.com B. Sana e-mail ... users (had not used transit in past 12 months), they were asked about their familiarity with the transit schedules, routes available, fare payment options ...
Transportation Research Record: Journal of the Transportation Research Board, 2004
The San Francisco Bay Area Water Transit Authority is evaluating expanded ferry service, as requi... more The San Francisco Bay Area Water Transit Authority is evaluating expanded ferry service, as required by the California legislature. Predicting ferry ridership has historically been difficult because water-transit riders often choose their travel mode based on factors other than travel time and cost. Most forecast models place a premium on time and cost and ignore other traveler attitudes. Structural equation modeling was used to identify simultaneously travel behavior and the causal relationships between a traveler's socioeconomic profile and travel attitudes. These market segments were used to estimate stated-preference (SP) mode choice models for 14 alternative modes, which separated the traveler's reaction to time savings by market segment and recognized that modal choices were different for market segments that were sensitive to travel stress or a desire to help the environment. The focus was on the application of the model to evaluate three future-year alternatives and ...
Transportation Research Record: Journal of the Transportation Research Board, 2002
Results of a design process for new integrated land use and transportation models recently comple... more Results of a design process for new integrated land use and transportation models recently completed for the Puget Sound Regional Council (PSRC) are presented. The design process, which began with an analysis of policy requirements and assessment of the current models in use at PSRC and nationally, employed an iterative and participatory approach to ensure that model requirements were clearly identified and that the proposed model design would address those requirements. Development of the model requirements drew on a broad survey of the literature and of operational models; the proposed model design offers a unique approach to the development of a new land use and travel model system that corresponds to a behavioral integration of the choice processes across relevant time frames.
Transportation Research Record: Journal of the Transportation Research Board, 1998
As the demand for using park-and-ride lots grows, the need to accurately forecast these trips als... more As the demand for using park-and-ride lots grows, the need to accurately forecast these trips also grows. Initially, demand for park-and-ride lots was forecast using a technique that identified the draw area for each lot and estimated demand without regard to capacity. These were simplifying assumptions that are no longer appropriate with respect to current demand for park-and-ride lots. In King County, Washington, the 12 largest park-and-ride lots are currently operating at 95 percent utilization. According to a recent park-and-ride lot survey in King County, there is significant latent demand for using lots that are full. The analysis of demand for parking in park-and-ride lots in King County was developed as part of the Washington State Department of Transportation Public/Private Partnership Program for the Park-and-Ride Capacity Enhancement Project. There were 17 park-and-ride lots considered for capacity enhancement. The approach to evaluate park-and-ride lot demand uses a tech...
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