11th World Conference on Transport ResearchWorld Conference on Transport Research Society, 2007
This paper describes how a statewide urban growth model for California will be run in iteration w... more This paper describes how a statewide urban growth model for California will be run in iteration with the California statewide travel model in order to evaluate major transportation scenarios, such as freeway widenings and high speed rail. In addition, the paper will evaluate land use policies intended to provide for more affordable housing and for habitat protection. This model provides performance measures for travel, economic welfare and equity, rents paid, energy use, greenhouse gas emissions, vehicular air pollution, and habitat loss. The authors propose a framework for interpreting these data, based on recent advances in the theories of well-being for persons and for nations.
In this paper, we report the preliminary results of the sensitivity test for California Productio... more In this paper, we report the preliminary results of the sensitivity test for California Production, Exchange and Consumption Allocation System (PECAS). The sensitivity test includes three scenarios: PECAS Only, Integrated, and High Travel Cost. The PECAS Only scenario allocates production and consumption at a fixed travel cost from years 2000 to 2020. It shows that the floorspace growth is more affected by general plan than travel cost, and residential floorspace types have higher growth rates in suburb, exurb and rural areas. Additionally, nonresidential (industrial and commercial) floorspace types have higher growth rates in the inner urban areas. The Integrated scenario has a more compact land use pattern than the PECAS Only scenario. Compared with the Integrated scenario, the High Travel Cost scenario leads to more compact use. The results from all three scenarios imply that the model behaves as expected and the outputs are consistent with what has been theorized.
Urban and regional air pollution is an increasingly critical problem in areas where rapid growth ... more Urban and regional air pollution is an increasingly critical problem in areas where rapid growth is occurring and future development is expected. Within the typical planning horizon, many modeling tools (e.g., land use, travel demand, and emissions models) are used to evaluate the impact of regional development, population trends, and infrastructure improvements on air quality. However, these models were not designed, nor are they generally used as a cohesive system with feedbacks between them. Consequently, there is a gap in our understanding of how different models interact and combine to influence emissions inventories associated with future policy scenarios. In this study, funded by the Environmental Protection Agency, an emissions modeling framework was developed using the UPlan, TP+/Viper, and UCDrive emission models for the San Joaquin Valley (SJV) in central California. Specifically, future land use and subsequent travel patterns and emissions inventories were examined based on four policy scenarios for the year 2030: baseline (following general plans, with no roadway expansion), controlled growth (compact urban boundary, higher residential densities, no roadway expansion), uncontrolled growth (low residential densities, roadway expansion), and as-planned (following general plans, with roadway expansion). The integrated modeling framework links emissions to levels of travel pattern variations under different land use policy and development strategies. For example, compared to a scenario with highly controlled urban growth strategies, less restraint on urban growth results in more than a 20% increase in vehicle miles traveled and about 18% higher emissions of primary pollutants at the regional scale in year 2030. By means of comparing and connecting land use, travel patterns and emissions, the sensitivity of SJV mobile emission inventories to different possible growth scenarios can be assessed.
eScholarship provides open access, scholarly publishing services to the University of California ... more eScholarship provides open access, scholarly publishing services to the University of California and delivers a dynamic research platform to scholars worldwide.
The California statewide integrated land use and transportation modeling has being developed usin... more The California statewide integrated land use and transportation modeling has being developed using the PECAS framework. This paper focus on two goals: a) presenting a framework for identifying household lifestyle clusters, and b) applying them to a spatial economic model system. A household's lifestyle is defined by two sets of dimensions: space use and household wage. Using a two-step clustering algorithm, different household lifestyle clusters were identified. The applicability of these lifestyle clusters for a integrated land use and transportation model was explored.
In this study, the authors discussed the advantages of using behavior based travel impedance at d... more In this study, the authors discussed the advantages of using behavior based travel impedance at disaggregate level and gravity factors in destination choice for non-commute trips, and empirically demonstrate how these variables improve the destination choice model. The authors found that 1) the time impedance based on individual behavior is a determinant of destination choice for non-commute trips. Travelers prefer closer locations to where they live; 2) the gravity factors (including zone size and trip length) have a significant impact on destination choice behavior. The zones with high gravity are more likely to be chosen as the destinations. The Zone Size, has a positive impact on destination choice while the distance lowers the utility of destination choice and has a negative impact on destination choice; 3) people with higher income travels farther; 4) younger people travels farther.
Using census block groups data on socio-demographics, land use, and travel behavior, we test the ... more Using census block groups data on socio-demographics, land use, and travel behavior, we test the cutoffs suggested in the literature for trustworthy estimates and hypothesis testing statistics, and evaluate the efficacy of deleting observations as an approach to improving multivariate normality, in structural equation modeling. The results show that the measures of univariate and multivariate non-normalities will fall into the acceptable ranges for trustworthy maximum likelihood estimation after a few true outliers are deleted. We argue that pursuing a multivariate normal distribution by deleting observations should be balanced against loss of model power in the interpretation of the results. Non-normality of Data in Structural Equation Models Shengyi Gao Dept. of Environmental Science and Policy University of California One Shields Ave. Davis, CA 95616 sgao@ucdavis.edu Phone: (530) 752-6303 Fax: (530)752-3350 Patricia L. Mokhtarian Dept. of Civil and Environmental Engineering Unive...
In this study, authors use a structural equation modeling approach to test the impacts of leisure... more In this study, authors use a structural equation modeling approach to test the impacts of leisure purpose and environmental factors on the elders’ leisure features, location choice, and related travel behavior. The results showed that leisure purpose had significant direct impacts on leisure features and locations but had no direct effects on leisure related travel behavior. Environmental factors had only direct effects on leisure locations and indirect effects on leisure related travel behavior. The results suggest that community parks and neighborhood green fields were more important to the elders’ leisure activities than large city parks due to high proximity and thus should be deliberately planned to improve the elders’ well-being in urban land use development.
11th World Conference on Transport ResearchWorld Conference on Transport Research Society, 2007
This paper describes how a statewide urban growth model for California will be run in iteration w... more This paper describes how a statewide urban growth model for California will be run in iteration with the California statewide travel model in order to evaluate major transportation scenarios, such as freeway widenings and high speed rail. In addition, the paper will evaluate land use policies intended to provide for more affordable housing and for habitat protection. This model provides performance measures for travel, economic welfare and equity, rents paid, energy use, greenhouse gas emissions, vehicular air pollution, and habitat loss. The authors propose a framework for interpreting these data, based on recent advances in the theories of well-being for persons and for nations.
In this paper, we report the preliminary results of the sensitivity test for California Productio... more In this paper, we report the preliminary results of the sensitivity test for California Production, Exchange and Consumption Allocation System (PECAS). The sensitivity test includes three scenarios: PECAS Only, Integrated, and High Travel Cost. The PECAS Only scenario allocates production and consumption at a fixed travel cost from years 2000 to 2020. It shows that the floorspace growth is more affected by general plan than travel cost, and residential floorspace types have higher growth rates in suburb, exurb and rural areas. Additionally, nonresidential (industrial and commercial) floorspace types have higher growth rates in the inner urban areas. The Integrated scenario has a more compact land use pattern than the PECAS Only scenario. Compared with the Integrated scenario, the High Travel Cost scenario leads to more compact use. The results from all three scenarios imply that the model behaves as expected and the outputs are consistent with what has been theorized.
Urban and regional air pollution is an increasingly critical problem in areas where rapid growth ... more Urban and regional air pollution is an increasingly critical problem in areas where rapid growth is occurring and future development is expected. Within the typical planning horizon, many modeling tools (e.g., land use, travel demand, and emissions models) are used to evaluate the impact of regional development, population trends, and infrastructure improvements on air quality. However, these models were not designed, nor are they generally used as a cohesive system with feedbacks between them. Consequently, there is a gap in our understanding of how different models interact and combine to influence emissions inventories associated with future policy scenarios. In this study, funded by the Environmental Protection Agency, an emissions modeling framework was developed using the UPlan, TP+/Viper, and UCDrive emission models for the San Joaquin Valley (SJV) in central California. Specifically, future land use and subsequent travel patterns and emissions inventories were examined based on four policy scenarios for the year 2030: baseline (following general plans, with no roadway expansion), controlled growth (compact urban boundary, higher residential densities, no roadway expansion), uncontrolled growth (low residential densities, roadway expansion), and as-planned (following general plans, with roadway expansion). The integrated modeling framework links emissions to levels of travel pattern variations under different land use policy and development strategies. For example, compared to a scenario with highly controlled urban growth strategies, less restraint on urban growth results in more than a 20% increase in vehicle miles traveled and about 18% higher emissions of primary pollutants at the regional scale in year 2030. By means of comparing and connecting land use, travel patterns and emissions, the sensitivity of SJV mobile emission inventories to different possible growth scenarios can be assessed.
eScholarship provides open access, scholarly publishing services to the University of California ... more eScholarship provides open access, scholarly publishing services to the University of California and delivers a dynamic research platform to scholars worldwide.
The California statewide integrated land use and transportation modeling has being developed usin... more The California statewide integrated land use and transportation modeling has being developed using the PECAS framework. This paper focus on two goals: a) presenting a framework for identifying household lifestyle clusters, and b) applying them to a spatial economic model system. A household's lifestyle is defined by two sets of dimensions: space use and household wage. Using a two-step clustering algorithm, different household lifestyle clusters were identified. The applicability of these lifestyle clusters for a integrated land use and transportation model was explored.
In this study, the authors discussed the advantages of using behavior based travel impedance at d... more In this study, the authors discussed the advantages of using behavior based travel impedance at disaggregate level and gravity factors in destination choice for non-commute trips, and empirically demonstrate how these variables improve the destination choice model. The authors found that 1) the time impedance based on individual behavior is a determinant of destination choice for non-commute trips. Travelers prefer closer locations to where they live; 2) the gravity factors (including zone size and trip length) have a significant impact on destination choice behavior. The zones with high gravity are more likely to be chosen as the destinations. The Zone Size, has a positive impact on destination choice while the distance lowers the utility of destination choice and has a negative impact on destination choice; 3) people with higher income travels farther; 4) younger people travels farther.
Using census block groups data on socio-demographics, land use, and travel behavior, we test the ... more Using census block groups data on socio-demographics, land use, and travel behavior, we test the cutoffs suggested in the literature for trustworthy estimates and hypothesis testing statistics, and evaluate the efficacy of deleting observations as an approach to improving multivariate normality, in structural equation modeling. The results show that the measures of univariate and multivariate non-normalities will fall into the acceptable ranges for trustworthy maximum likelihood estimation after a few true outliers are deleted. We argue that pursuing a multivariate normal distribution by deleting observations should be balanced against loss of model power in the interpretation of the results. Non-normality of Data in Structural Equation Models Shengyi Gao Dept. of Environmental Science and Policy University of California One Shields Ave. Davis, CA 95616 sgao@ucdavis.edu Phone: (530) 752-6303 Fax: (530)752-3350 Patricia L. Mokhtarian Dept. of Civil and Environmental Engineering Unive...
In this study, authors use a structural equation modeling approach to test the impacts of leisure... more In this study, authors use a structural equation modeling approach to test the impacts of leisure purpose and environmental factors on the elders’ leisure features, location choice, and related travel behavior. The results showed that leisure purpose had significant direct impacts on leisure features and locations but had no direct effects on leisure related travel behavior. Environmental factors had only direct effects on leisure locations and indirect effects on leisure related travel behavior. The results suggest that community parks and neighborhood green fields were more important to the elders’ leisure activities than large city parks due to high proximity and thus should be deliberately planned to improve the elders’ well-being in urban land use development.
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