Browsing by Subject "GPS"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Association of environmental indicators with teen alcohol use and problem behavior: Teens' observations vs. objectively-measured indicators
    (Elsevier, 2017-01) Byrnes, Hilary F.; Miller, Brenda A.; Morrison, Christopher N.; Wiebe, Douglas J.; Woychik, Marcie; Wiehe, Sarah E.; Medicine, School of Medicine
    Most prior studies use objectively measured data (e.g., census-based indicators) to assess contextual risks. However, teens' observations might be more important for their risk behavior. OBJECTIVES: 1) determine relationships between observed and objective indicators of contextual risks 2) determine relations of observed and objective indicators with teen alcohol use and problem behavior. Teens aged 14-16 (N=170) carried GPS-enabled smartphones for one month, with locations documented. Ecological momentary assessment (EMA) measured teens' observations via texts regarding risk behaviors and environmental observations. Objective indicators of alcohol outlets and disorganization were spatially joined to EMAs based on teens' location at the time of the texts. Observed and objective disorganization, and objective indicators of alcohol outlets were related to alcohol use. Observed disorganization was related to problem behavior, while objective indicators were unrelated. Findings suggest the importance of considering teens' observations of contextual risk for understanding influences on risk behavior and suggest future directions for research and prevention strategies.
  • Thumbnail Image
    Item
    Brief report: Using global positioning system (GPS) enabled cell phones to examine adolescent travel patterns and time in proximity to alcohol outlets
    (Elsevier, 2016-07) Byrnes, Hilary F.; Miller, Brenda A.; Morrison, Christopher N.; Wiebe, Douglas J.; Remer, Lillian G.; Wiehe, Sarah E.; Department of Pediatrics, IU School of Medicine
    As adolescents gain freedom to explore new environments unsupervised, more time in proximity to alcohol outlets may increase risks for alcohol and marijuana use. This pilot study: 1) Describes variations in adolescents' proximity to outlets by time of day and day of the week, 2) Examines variations in outlet proximity by drinking and marijuana use status, and 3) Tests feasibility of obtaining real-time data to study adolescent proximity to outlets. U.S. adolescents (N = 18) aged 16–17 (50% female) carried GPS-enabled smartphones for one week with their locations tracked. The geographic areas where adolescents spend time, activity spaces, were created by connecting GPS points sequentially and adding spatial buffers around routes. Proximity to outlets was greater during after school and evening hours. Drinkers and marijuana users were in proximity to outlets 1½ to 2 times more than non-users. Findings provide information about where adolescents spend time and times of greatest risk, informing prevention efforts.
  • Thumbnail Image
    Item
    Visitor bikeshare usage: tracking visitor spatiotemporal behavior using big data
    (Taylor & Francis, 2020-09-11) Buning, Richard J; Lulla, Vijay
    Bikeshare programs are a popular, convenient, and sustainable mode of transportation that provide a range of benefits to urban communities such as reduction in carbon emissions, decreased travel times, financial savings, and heightened physical activity. Although, tourists are especially inclined to use bikeshare to explore a destination as the programs are a convenient, cheap, flexible, and an active alternative to vehicles and mass transit little research or attention has focused on visitor usage. As such the current study investigated the spatial-temporal usage patterns of bikeshare by visitors to an urban community using GPS based big data (N = 353,733). The results revealed differential usage patterns between visitors and local residents based on user provided ZIP Codes using a 50 mile geometric circular buffer around the urban destination. The visitors and residents significantly varied on numerous trip behaviors including route selection, time of rental, checkout/check-in locations, distance, speed, duration, and physical activity intensity. The user patterns uncovered suggest visitors primarily use bikeshare for leisure based urban exploration, compared to residents’ primary use of bikeshare to be public transportation related. Implications for bikeshare, urban planning, and tourism management are provided aimed at delivering a more sustainable and richer visitor experience.