Kang, Bumjoon; Moudon, Anne V.; Hurvitz, Philip M.; Reichley, Lucas; Saelens, Brian E. (2013). Walking Objectively Measured: Classifying Accelerometer Data with GPS and Travel Diaries. Medicine & Science In Sports & Exercise, 45(7), 1419 – 1428.
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Abstract
Purpose: This study developed and tested an algorithm to classify accelerometer data as walking or nonwalking using either GPS or travel diary data within a large sample of adults under free-living conditions. Methods: Participants wore an accelerometer and a GPS unit and concurrently completed a travel diary for seven consecutive days. Physical activity (PA) bouts were identified using accelerometry count sequences. PA bouts were then classified as walking or nonwalking based on a decision-tree algorithm consisting of seven classification scenarios. Algorithm reliability was examined relative to two independent analysts' classification of a 100-bout verification sample. The algorithm was then applied to the entire set of PA bouts. Results: The 706 participants' (mean age = 51 yr, 62% female, 80% non-Hispanic white, 70% college graduate or higher) yielded 4702 person-days of data and had a total of 13,971 PA bouts. The algorithm showed a mean agreement of 95% with the independent analysts. It classified PA into 8170 walking bouts (58.5 %) and 5337 nonwalking bouts (38.2%); 464 bouts (3.3%) were not classified for lack of GPS and diary data. Nearly 70% of the walking bouts and 68% of the nonwalking bouts were classified using only the objective accelerometer and GPS data. Travel diary data helped classify 30% of all bouts with no GPS data. The mean + SD duration of PA bouts classified as walking was 15.2 + 12.9 min. On average, participants had 1.7 walking bouts and 25.4 total walking minutes per day. Conclusions: GPS and travel diary information can be helpful in classifying most accelerometer-derived PA bouts into walking or nonwalking behavior.
Keywords
Walking; Algorithms; Decision Trees; Geographic Information Systems; Research Funding; Travel; Accelerometry; Diary (literary Form); Descriptive Statistics; Algorithm; Classification; Physical Activity; Walk Trip; Global Positioning Systems; Physical-activity; Environment; Behaviors; Validity; Location
Hoofnagle, Chris Jay; Whittington, Jan. (2014). Free: Accounting for the Costs of the Internet’s Most Popular Price. UCLA Law Review, 61(3), 606 – 670.
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Abstract
Offers of free services abound on the Internet. But the focus on the price rather than on the cost of free services has led consumers into a position of vulnerability. For example, even though internet users typically exchange personal information for the opportunity to use these purportedly free services, one court has found that users of free services are not consumers for purposes of California consumer protection law. This holding reflects the common misconception that the costs of free online transactions are negligible when in fact true costs may be quite significant. To elucidate the true costs of these allegedly free services, we apply a transaction cost economics (TCE) approach. Unlike orthodox economic theory, TCE provides a framework for analyzing exchanges in which the price of the product seems to be zero. Under a TCE analysis, we argue that information-intensive companies misuse the term free to promote products and services that involve numerous nonpecuniary costs. In so doing, firms generate contractual hazards for consumers, ignore consumer preferences for privacy, and mislead consumers by creating the impression that a given transaction will be free. While psychological research and behavioral economics may support an outright ban of free offers because of their biasing effects, TCE suggests reforming governance structures to place the business risks associated with free transactions more firmly in the hands of businesses. We suggest alterations to governance structures such as the Federal Trade Commission's Guide Concerning Use of the Word Free (FTC Guide) to curb the incentives of firms to raise transaction costs for consumers. The FTC Guide provides support for two of the consumer protection measures we propose: first, a requirement that free service providers clearly disclose that such providers seek users' personal information in exchange for those services, and, second, the establishment of a regular price before providers can market a service as free. We further argue that the recognition of users of free services as consumers for purposes of consumer protection law would better align incentives and ensure users access to legal redress against some of the most popular services on the Internet. Lastly, we suggest the adoption of alternative governance structures designed to reduce the cost of transacting by curbing the collection of personal information from consumers of free services and by enhancing the rights of consumers to govern the dispersal of personal information from free online services to third parties.
Keywords
Free Internet Service Providers; Internet Usage Monitoring; Transaction Cost Theory Of The Firm; Internet Privacy -- Law & Legislation; Law; United States. Federal Trade Commission; Vertical Integration; Privacy
Huang, R.; Moudon, A. V.; Cook, A. J.; Drewnowski, A. (2015). The Spatial Clustering of Obesity: Does the Built Environment Matter? Journal Of Human Nutrition & Dietetics, 28(6), 604 – 612.
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Abstract
BackgroundObesity rates in the USA show distinct geographical patterns. The present study used spatial cluster detection methods and individual-level data to locate obesity clusters and to analyse them in relation to the neighbourhood built environment. MethodsThe 2008-2009 Seattle Obesity Study provided data on the self-reported height, weight, and sociodemographic characteristics of 1602 King County adults. Home addresses were geocoded. Clusters of high or low body mass index were identified using Anselin's Local Moran's I and a spatial scan statistic with regression models that searched for unmeasured neighbourhood-level factors from residuals, adjusting for measured individual-level covariates. Spatially continuous values of objectively measured features of the local neighbourhood built environment (SmartMaps) were constructed for seven variables obtained from tax rolls and commercial databases. ResultsBoth the Local Moran's I and a spatial scan statistic identified similar spatial concentrations of obesity. High and low obesity clusters were attenuated after adjusting for age, gender, race, education and income, and they disappeared once neighbourhood residential property values and residential density were included in the model. ConclusionsUsing individual-level data to detect obesity clusters with two cluster detection methods, the present study showed that the spatial concentration of obesity was wholly explained by neighbourhood composition and socioeconomic characteristics. These characteristics may serve to more precisely locate obesity prevention and intervention programmes.
Keywords
Real Property; Ecology; Age Distribution; Anthropometry; Black People; Cluster Analysis (statistics); Communities; Computer Software; Epidemiological Research; Geographic Information Systems; Hispanic Americans; Mathematics; Obesity; Population Geography; Probability Theory; Race; Regression Analysis; Research Funding; Restaurants; Statistical Sampling; Self-evaluation; Sex Distribution; Shopping; Surveys; Telephones; Transportation; White People; Socioeconomic Factors; Body Mass Index; Data Analysis Software; Medical Coding; Statistical Models; Descriptive Statistics; Odds Ratio; Economics; Washington (state); Built Environment; Local Moran's I; Spatial Scan Statistic; Body-mass Index; Physical-activity; United-states; Risk-factors; Neighborhood; Association; Density; Disease; Disparities; Prevalence
Drewnowski, Adam; Aggarwal, Anju; Tang, Wesley; Hurvitz, Philip M.; Scully, Jason; Stewart, Orion; Moudon, Anne Vernez. (2016). Obesity, Diet Quality, Physical Activity, and the Built Environment: The Need for Behavioral Pathways. BMC Public Health, 16.
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Abstract
Background: The built environment ( BE) is said to influence local obesity rates. Few studies have explored causal pathways between home-neighborhood BE variables and health outcomes such as obesity. Such pathways are likely to involve both physical activity and diet. Methods: The Seattle Obesity Study ( SOS II) was a longitudinal cohort of 440 adult residents of King Co, WA. Home addresses were geocoded. Home-neighborhood BE measures were framed as counts and densities of food sources and physical activity locations. Tax parcel property values were obtained from County tax assessor. Healthy Eating Index ( HEI 2010) scores were constructed using data from food frequency questionnaires. Physical activity ( PA) was obtained by self-report. Weights and heights were measured at baseline and following 12 months' exposure. Multivariable regressions examined the associations among BE measures at baseline, health behaviors ( HEI-2010 and physical activity) at baseline, and health outcome both cross-sectionally and longitudinally. Results: None of the conventional neighborhood BE metrics were associated either with diet quality, or with meeting PA guidelines. Only higher property values did predict better diets and more physical activity. Better diets and more physical activity were associated with lower obesity prevalence at baseline and 12 mo, but did not predict weight change. Conclusion: Any links between the BE and health outcomes critically depend on establishing appropriate behavioral pathways. In this study, home-centric BE measures, were not related to physical activity or to diet. Further studies will need to consider a broader range of BE attributes that may be related to diets and health.
Keywords
Body-mass Index; Local Food Environment; Residential Property-values; Supermarket Accessibility; Park Proximity; Neighborhood Walkability; Vegetable Consumption; Atherosclerosis Risk; Restaurant Food; Associations; Built Environment; Physical Activity; Obesity; Diet Quality
Schmiedeskamp, Peter; Zhao, Weiran. (2016). Estimating Daily Bicycle Counts in Seattle, Washington, from Seasonal and Weather Factors. Transportation Research Record, 2593, 94 – 102.
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Abstract
This paper examines the relationship between several seasonal and weather factors and bicycle ridership from 2 years of automated bicycle counts at a location in Seattle, Washington. The authors fitted a negative binomial model and then estimated quantities of interest using counterfactual simulation. The findings confirm the significance of season (+), temperature (+), precipitation (), as well as holidays (-), day of the week (+ for Monday through Saturday, relative to Sunday), and an overall trend (+). This paper improves on prior work by demonstrating the use of the negative binomial instead of a Poisson model, which is appropriate given the potential for overdispersion, as observed in these data. In addition to validating the significance of factors identified from the literature, this paper contributes methodologically through its intuitive visualization of effect sizes to nonstatistical audiences. The authors believe that the combination of model type and counterfactual simulation and visualization reflects a reasonable compromise between model complexity and interpretability. Results such as these can aid policy makers and planners in understanding bicycle travel demand elasticities and in guiding interventions aimed at increasing rates of bicycling. The methods presented are fully reproducible and invite adaptation to other locations.
Grover, Himanshu; Brody, Samuel D.; Vedlitz, Arnold. (2017). Understanding Climate Change Risk Perception in the USA. International Journal Of Global Warming, 13(2), 113 – 137.
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Abstract
Public perceptions of risk from climate change are an important determinant of the willingness of citizens to support climate change mitigation and adaptation policies. Although there is a growing body of research focusing on a variety of individual, cultural, and organisational factors that affect an individual's perception of risk, only a few studies have adopted a multivariate analytical approach to understand public perceptions of climate change risks. This study extends earlier interdisciplinary research initiatives and proposes a more comprehensive, integrated model for understanding climate change risk perception. Using measures of objective risk, individual climate stress, and individual capacity, we explain public perceptions of climate change risks. The analysis is based on a national representative survey of US citizens. Geographic information systems and spatial analytical techniques are used to supplement the survey data with measures of objective risk associated with the location of each respondent. Analysis of the data using multivariate regression suggests that increased objective risk and individual capacity result in significantly higher perception of risk from climate change, whereas higher individual climate stress results in lower risk perceptions.
Keywords
United-states; Public Support; Experience; Adaptation; Beliefs; Gender; Impact; Policy; Representations; Communication; Climate Change; Risk Perception; Objective Risk; Individual Climate Stress; Individual Capacity; Data Processing; Perceptions; Geographic Information Systems; Mitigation; Interdisciplinary Research; Multivariate Analysis; Environmental Risk; Regression Analysis; Environmental Policy; Perception; Interdisciplinary Studies; Remote Sensing; Information Systems; Analytical Techniques; Surveying; Policies; Research; Capacity; Adaptations; Climatic Changes; Gis; Climatic Analysis; Climate Models; Research & Development--r&d; Climate Change Mitigation; United States--us
Dannenberg, Andrew L.; Burpee, Heather. (2018). Architecture for Health Is Not Just for Healthcare Architects. Health Environments Research & Design Journal (herd) (sage Publications, Ltd.), 11(2), 8 – 12.
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Keywords
Building Design & Construction; Public Health; Quality Of Life; Built Environment; Public Spaces
Wentz, Elizabeth A.; York, Abigail M.; Alberti, Marina; Conrow, Lindsey; Fischer, Heather; Inostroza, Luis; Jantz, Claire; Pickett, Steward T. A.; Seto, Karen C.; Taubenboeck, Hannes. (2018). Six Fundamental Aspects for Conceptualizing Multidimensional Urban Form: A Spatial Mapping Perspective. Landscape And Urban Planning, 179, 55 – 62.
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Abstract
Urbanization is currently one of the most profound transformations taking place across the globe influencing the flows of people, energy, and matter. The urban form influences and is influenced by these flows and is therefore critical in understanding and how urban areas affect and are affected by form. Nevertheless, there is a lack of uniformity in how urban form is analyzed. Urban form analyzed from a continuum of a simple urban versus non-urban classification to highly detailed representations of land use and land cover. Either end of the representation spectrum limits the ability to analyze within-urban dynamics, to make cross-city comparisons, and to produce generalizable results. In the framework of remote sensing and geospatial analysis, we identify and define six fundamental aspects of urban form, which are organized within three overarching components. Materials, or the physical elements of the urban landscape, consists of three aspects (1) human constructed elements, (2) the soil-plant continuum, and (3) water elements. The second component is configuration, which includes the (4) two- and three-dimensional space and (5) spatial pattern of urban areas. Lastly, because of the dynamics of human activities and biophysical processes, an important final component is the change of urban form over (6) time. We discuss how a this urban form framework integrates into a broader discussion of urbanization.
Keywords
Ecosystem Services; Land-use; Reconceptualizing Land; Cellular-automata; Heterogeneity; Framework; Model; Emissions; Dynamics; Cities; Gis; Remote Sensing; Land Use; Land Cover; Urban Form; Urban Materials; Energy; Humans; Land Use And Land Cover Maps; Landscapes; Urban Areas; Urbanization
Moudon, Anne Vernez. (2019). Introducing Supergrids, Superblocks, Areas, Networks, and Levels to Urban Morphological Analyses. Iconarp International Journal Of Architecture And Planning, 7, 1 – 14.
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Abstract
Urban morphological analyses have identified the parcel (plot), the building type, or the plan unit (tessuto in Italian) as the basic elements of urban form. As cities have grown in geographic size disproportionately to their growth in population over the past seven decades, new elements have been introduced that structure their form. This essay describes these new elements and proposes that they be formally recognized in urban morphology. It introduces a conceptual framework for a multilevel structure of urban space using areas and networks and including supergrids and superblocks to guide morphological analyses.
Keywords
Morphological Elements; A Posteriori Approach; A Priori Approach
Bautista-Hernández, Dorian. (2020). Urban Structure and its Influence on Trip Chaining Complexity in the Mexico City Metropolitan Area. Urban, Planning And Transport Research, 8(1), 71 – 97.
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Abstract
This project studies the relationship between the urban structure of the Mexico City Metropolitan Area (MCMA) and two aspects of commuter travel patterns: (1) number of stops in a tour and (2) complexity of trip chaining. Two regression models were explored, one for each dependent variable of interest. The analysis was applied for car drivers, transit users and travelers with mixed transportation separately. Covariates include individual, household, travel and urban form variables, which showed differential effects according to the transportation mode. According to the number of significant covariates, it can be said that there is less impact of urban form on trip generation and complexity of travel for car drivers (only mixed land use at destination being significant for complexity of travel) and mixed transportation (being only significant job access for complexity of travel) than for transit users (being significant job access, population density, mixed land use at origin for extra trip, number of trips and complexity of travel). The directions of these effects vary according to the transportation mode and are discussed in terms of reported literature.
Keywords
Trip Generation; Urban Structures; Chaining; Drivers; Population Density; Land Use; Regression Analysis; Regression Models; Transportation; Travel; Complexity; Automobile Drivers; Metropolitan Areas; Travel Patterns; Urban Areas; Dependent Variables; Mexico