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Browsing by Author "Liu, Shirley Shiqin"

Now showing 1 - 15 of 15
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    Access Across America: Auto 2021
    (Center for Transportation Studies, University of Minnesota, 2023-07) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Lind, Eric
    Accessibility is the ease and feasibility of reaching valued destinations. It can be measured for a wide array of transportation modes, to different types of destinations, and at different times of day. There are a variety of ways to define accessibility, but the number of destinations reachable within a given travel time is the most comprehensible and transparent as well as the most directly comparable across cities. This study estimates the accessibility to jobs by auto for each of the 11 million U.S. census blocks and analyzes these data in the 50 largest (by population) metropolitan areas. Travel times are calculated using a detailed road network and speed data that reflect typical conditions for an 8 a.m. Wednesday morning departure. Additionally, the accessibility results for 8 a.m. are compared with accessibility results for 4 a.m. to estimate the impact of road and highway congestion on job accessibility. Rankings are determined by a weighted average of accessibility, with a higher weight given to closer, easier-to-access jobs. Jobs reachable within 10 minutes are weighted most heavily, and jobs are given decreasing weights as travel time increases up to 60 minutes. This report presents detailed accessibility values for each metropolitan area, as well as block-level maps which illustrate the spatial patterns of accessibility within each area. Year-over-year changes in accessibility, and in congestion impacts on accessibility, are provided for each area. The 2021 reporting year reflects the first travel year after the onset of the COVID-19 pandemic; thus the changes in accessibility include impacts of reduced congestion and higher peak speeds due to changes in travel behavior, especially reductions in office commutes due to telework.
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    Access Across America: Auto 2021 Data
    (2023-09-21) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Hockert, Matthew; Lind, Eric; owenx148@umn.edu; Owen, Andrew; University of Minnesota Center for Transportation Studies, Accessibility Observatory
    These data were created as part of a study that examined the accessibility to jobs by auto in the 50 largest (by population) metropolitan areas in the United States. The data include access at realistic observed driving speeds by time of day and road segment. The underlying speed data inputs restrict data sharing to participating sponsor states. The data available describe access to jobs by auto in the states/districts of California, Connecticut, District of Columbia, Florida, Illinois, Maryland, Massachusetts, Michigan, Minnesota, North Carolina, Texas; and the metropolitan areas within these states. These data are part of a longitudinal study. Auto data for additional years can be found in the Accessibility Observatory Data collection: http://hdl.handle.net/11299/200592
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    Access Across America: Auto 2022
    (Center for Transportation Studies, University of Minnesota, 2024-09) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Lind, Eric
    Accessibility is the ease and feasibility of reaching valued destinations. It can be measured for a wide array of transportation modes, to different types of destinations, and at different times of day. There are a variety of ways to define accessibility, but the number of destinations reachable within a given travel time is the most comprehensible and transparent as well as the most directly comparable across cities. This study estimates the accessibility to jobs by auto for each of the 11 million U.S. census blocks and analyzes these data in the 50 largest (by population) metropolitan areas. Travel times are calculated using a detailed road network and speed data that reflect typical conditions for an 8 a.m. Wednesday morning departure. Additionally, the accessibility results for 8 a.m. are compared with accessibility results for 4 a.m. to estimate the impact of road and highway congestion on job accessibility. Rankings are determined by a weighted average of accessibility, with a higher weight given to closer, easier-to-access jobs. Jobs reachable within 10 minutes are weighted most heavily, and jobs are given decreasing weights as travel time increases up to 60 minutes. This report presents detailed accessibility values for each metropolitan area, as well as block-level maps which illustrate the spatial patterns of accessibility within each area. Year-over-year changes in accessibility, and in congestion impacts on accessibility, are provided for each area. The 2022 reporting year reflects the ongoing changes in local travel behavior after the onset of the COVID-19 pandemic, including some return of congestion and but still higher peak speeds due to reductions in office commutes due to telework.
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    Access Across America: Auto 2022 Data
    (2024-10-21) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Hockert, Matthew; Lind, Eric; owenx148@umn.edu; Owen, Andrew; University of Minnesota Center for Transportation Studies, Accessibility Observatory
    These data were created as part of a study that examined the accessibility to jobs by auto in the 50 largest (by population) metropolitan areas in the United States. The data include access at realistic observed driving speeds by time of day and road segment. The underlying speed data inputs restrict data sharing to participating sponsor states. The data available describe access to jobs by auto in the states/districts of California, Connecticut, District of Columbia, Florida, Illinois, Maryland, Massachusetts, Michigan, Minnesota, North Carolina, Texas, and Virginia; and the metropolitan areas within these states. These data are part of a longitudinal study. Auto data for additional years can be found in the Accessibility Observatory Data collection: http://hdl.handle.net/11299/200592
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    Access Across America: Bike 2021 Data
    (2023-08-28) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Hockert, Matthew; Lind, Eric; owenx148@umn.edu; Owen, Andrew; University of Minnesota Center for Transportation Studies, Accessibility Observatory
    These data were created as part of a study that examined the accessibility to jobs by bicycling across the United States. It is the most detailed evaluation to date of access to jobs by biking, and incorporates a Level of Traffic Stress analysis to allow calculation of access to jobs on bike networks of different traffic stress tolerances. This dataset allows for a direct comparison of the biking accessibility performance of America's largest metropolitan areas. These data are part of a longitudinal study. Previous datasets (Access Across America: Bike 2019) are available at https://conservancy.umn.edu/handle/11299/218194.
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    Access Across America: Bike 2022 Data
    (2024-10-21) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Hockert, Matthew; Lind, Eric; owenx148@umn.edu; Owen, Andrew; University of Minnesota Center for Transportation Studies, Accessibility Observatory
    These data were created as part of a study that examines the accessibility to jobs by biking across the United States. It is the most detailed evaluation to date of access to jobs by cycling, and it allows for a direct comparison of the bike accessibility performance of America's metropolitan areas. These data are part of a longitudinal study. Biking data for additional years can be found in the Accessibility Observatory Data collection: https://hdl.handle.net/11299/200592
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    Access Across America: Biking 2021
    (Center for Transportation Studies, University of Minnesota, 2023-07) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Lind, Eric
    Accessibility is the ease and feasibility of reaching valued destinations. It can be measured for a wide array of transportation modes, to different types of destinations, and at different times of day. There are a variety of ways to define accessibility, but the number of destinations reachable within a given travel time is the most comprehensible and transparent as well as the most directly comparable across cities. This study estimates the accessibility to jobs by biking for each of the United States' 11 million census blocks and analyzes these data in the 50 largest (by population) metropolitan areas. Travel times by biking are calculated using detailed roadway networks classified by their Level of Traffic Stress (LTS). Rankings are determined by a weighted average of job accessibility; a higher weight is given to closer jobs, as jobs closer to origins are more easily reached, and are thus more valuable, than those further away. Jobs reachable within ten minutes are weighted most heavily, and jobs are given decreasing weights as travel time increases up to 60 minutes. This report presents detailed accessibility values for each metropolitan area, as well as block-level maps which illustrate the spatial patterns of accessibility within each area. Year-over-year changes in accessibility by bike are provided for each area. The 2021 reporting year reflects the first travel year after the onset of the COVID-19 pandemic.
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    Access Across America: Biking 2022
    (Center for Transportation Studies, University of Minnesota, 2024-09) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Lind, Eric
    Accessibility is the ease and feasibility of reaching valued destinations. It can be measured for a wide array of transportation modes, to different types of destinations, and at different times of day. There are a variety of ways to define accessibility, but the number of destinations reachable within a given travel time is the most comprehensible and transparent as well as the most directly comparable across cities. This study estimates the accessibility to jobs by biking for each of the United States' 11 million census blocks and analyzes these data in the 50 largest (by population) metropolitan areas. Travel times by biking are calculated using detailed roadway networks classified by their Level of Traffic Stress (LTS). Rankings are determined by a weighted average of job accessibility; a higher weight is given to closer jobs, as jobs closer to origins are more easily reached, and are thus more valuable, than those further away. Jobs reachable within ten minutes are weighted most heavily, and jobs are given decreasing weights as travel time increases up to 60 minutes. This report presents detailed accessibility values for each metropolitan area, as well as block-level maps which illustrate the spatial patterns of accessibility within each area. Year-over-year changes in accessibility by bike are provided for each area. The 2022 reporting year reflects the changes in bike infrastructure some cities have made, in part responding to changing travel behavior after the onset of the COVID-19 pandemic.
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    Access Across America: Transit 2021
    (Center for Transportation Studies, University of Minnesota, 2023-07) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Lind, Eric
    Accessibility is the ease and feasibility of reaching valued destinations. It can be measured for a wide array of transportation modes, to different types of destinations, and at different times of day. There are a variety of ways to define accessibility, but the number of destinations reachable within a given travel time is the most comprehensible and transparent as well as the most directly comparable across cities. This study estimates the accessibility to jobs by transit and walking for each of the United States' 11 million census blocks and analyzes these data in the 50 largest (by population) metropolitan areas. Travel times by transit are calculated using detailed pedestrian networks and full transit schedules for the 7:00 - 9:00 a.m. period. The calculations include all components of a transit journey, including "last-mile" access and egress walking segments and transfers, and account for minute-by-minute variations in service frequency. This report presents detailed accessibility values for each metropolitan area, as well as block-level maps which illustrate the spatial patterns of accessibility within each area. Year-over-year changes in transit accessibility are provided for each area. The 2021 reporting year reflects the first travel year after the onset of the COVID-19 pandemic; thus the changes in accessibility include impacts of altered transit service in response to changes in travel behavior, especially reductions in office commutes due to telework.
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    Access Across America: Transit 2021 Data
    (2023-08-31) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Hockert, Matthew; Lind, Eric; owenx148@umn.edu; Owen, Andrew; University of Minnesota Center for Transportation Studies, Accessibility Observatory
    These data were created as part of a study that examined the accessibility to jobs by transit across the United States. It is the most detailed evaluation to date of access to jobs by transit, and it allows for a direct comparison of the transit accessibility performance of America's metropolitan areas. These data are part of a longitudinal study. Transit data for additional years can be found in the Accessibility Observatory Data collection: http://hdl.handle.net/11299/200592
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    Access Across America: Transit 2022
    (Center for Transportation Studies, University of Minnesota, 2024-09) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Lind, Eric
    Accessibility is the ease and feasibility of reaching valued destinations. It can be measured for a wide array of transportation modes, to different types of destinations, and at different times of day. There are a variety of ways to define accessibility, but the number of destinations reachable within a given travel time is the most comprehensible and transparent as well as the most directly comparable across cities. This study estimates the accessibility to jobs by transit and walking for each of the United States' 11 million census blocks and analyzes these data in the 50 largest (by population) metropolitan areas. Travel times by transit are calculated using detailed pedestrian networks and full transit schedules for the 7:00 - 9:00 a.m. period. The calculations include all components of a transit journey, including "last-mile" access and egress walking segments and transfers, and account for minute-by-minute variations in service frequency. This report presents detailed accessibility values for each metropolitan area, as well as block-level maps which illustrate the spatial patterns of accessibility within each area. Year-over-year changes in transit accessibility are provided for each area. The 2022 reporting year reflects the ongoing modification of transit service levels after the onset of the COVID-19 pandemic, and the impacts to transit agencies of workforce and budget limitations. Thus the changes in accessibility include impacts of altered transit service in response to these challenges, as well as reductions in office commutes due to telework.
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    Access Across America: Transit 2022 Data
    (2024-10-21) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Hockert, Matthew; Lind, Eric; owenx148@umn.edu; Owen, Andrew; University of Minnesota Center for Transportation Studies, Accessibility Observatory
    These data were created as part of a study that examines the accessibility to jobs by transit across the United States. It is the most detailed evaluation to date of access to jobs by transit, and it allows for a direct comparison of the transit accessibility performance of America's metropolitan areas. These data are part of a longitudinal study. Transit data for additional years can be found in the Accessibility Observatory Data collection: https://hdl.handle.net/11299/200592
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    Access Across America: Walk 2022
    (Center for Transportation Studies, University of Minnesota, 2024-09) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Lind, Eric
    Accessibility is the ease and feasibility of reaching valued destinations. It can be measured for a wide array of transportation modes, to different types of destinations, and at different times of day. There are a variety of ways to define accessibility, but the number of destinations reachable within a given travel time is the most comprehensible and transparent as well as the most directly comparable across cities. This study estimates the accessibility to jobs by walking or rolling for each of the United States' 11 million census blocks and analyzes these data in the 50 largest (by population) metropolitan areas. Travel times by walking or rolling are calculated using detailed pathway networks and low-speed streets. Rankings are determined by a weighted average of job accessibility; a higher weight is given to closer jobs, as jobs closer to origins are more easily reached, and are thus more valuable, than those further away. Jobs reachable within ten minutes are weighted most heavily, and jobs are given decreasing weights as travel time increases up to 60 minutes. This report presents detailed accessibility values for each metropolitan area, as well as block-level maps which illustrate the spatial patterns of accessibility within each area. Additionally, access to jobs by travel time is separately analyzed according to the income grouping of resident workers who experience that access. Because this is the first national pedestrian accessibility report since 2014, year-over-year changes in accessibility are not provided for each area. Future annual evaluations will include the changes over time.
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    Access Across America: Walk 2022 Data
    (2024-10-21) Owen, Andrew; Liu, Shirley Shiqin; Jain, Saumya; Hockert, Matthew; Lind, Eric; owenx148@umn.edu; Owen, Andrew; University of Minnesota Center for Transportation Studies, Accessibility Observatory
    These data were created as part of a study that examines the accessibility to jobs by walking or rolling across the United States. It is the most detailed evaluation to date of access to jobs by walking, and it allows for a direct comparison of the walkability of America's metropolitan areas. These data are part of a longitudinal study. Walk/roll data for additional years can be found in the Accessibility Observatory Data collection: https://hdl.handle.net/11299/200592
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    Access in Appalachia Pilot Implementation Project
    (Center for Transportation Studies, University of Minnesota, 2024-05) Jain, Saumya; Lind, Eric; Owen, Andrew; Liu, Shirley Shiqin
    The Access in Appalachia Pilot Implementation Project report is an exploration of transportation accessibility within the Appalachian Region. Here, Accessibility means the ease with which people can travel to valued destinations. Commissioned by the Appalachian Regional Commission (ARC) and led by the Maryland Department of Transportation State Highway Administration, this project represents a significant leap forward in the understanding of the intersections between economic development, land use, and transportation infrastructure. Through innovative methodologies this project measures, analyzes, and visualizes the access of Appalachian residents to critical opportunities, including jobs, education, healthcare, entertainment, and intermodal freight facilities. The analyses reveal critical insights into transportation dynamics, land use practices, and accessibility nuances, often marked by the urban vs rural landscape within the Appalachian region, offering pathways for strategic development. The report highlights need for tailored transportation strategies, informed decision-making, and equitable planning to address the diverse needs of Appalachia's varied landscapes to foster socio-economic growth.