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.
Chaix, Basile; Duncan, Dustin; Vallee, Julie; Vernez-moudon, Anne; Benmarhnia, Tarik; Kestens, Yan. (2017). The Residential Effect Fallacy in Neighborhood and Health Studies Formal Definition, Empirical Identification, and Correction. Epidemiology, 28(6), 789 – 797.
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Abstract
Background: Because of confounding from the urban/rural and socioeconomic organizations of territories and resulting correlation between residential and nonresidential exposures, classically estimated residential neighborhood-outcome associations capture nonresidential environment effects, overestimating residential intervention effects. Our study diagnosed and corrected this residential effect fallacy bias applicable to a large fraction of neighborhood and health studies. Methods: Our empirical application investigated the effect that hypothetical interventions raising the residential number of services would have on the probability that a trip is walked. Using global positioning systems tracking and mobility surveys over 7 days (227 participants and 7440 trips), we employed a multilevel linear probability model to estimate the trip-level association between residential number of services and walking to derive a naive intervention effect estimate and a corrected model accounting for numbers of services at the residence, trip origin, and trip destination to determine a corrected intervention effect estimate (true effect conditional on assumptions). Results: There was a strong correlation in service densities between the residential neighborhood and nonresidential places. From the naive model, hypothetical interventions raising the residential number of services to 200, 500, and 1000 were associated with an increase by 0.020, 0.055, and 0.109 of the probability of walking in the intervention groups. Corrected estimates were of 0.007, 0.019, and 0.039. Thus, naive estimates were overestimated by multiplicative factors of 3.0, 2.9, and 2.8. Conclusions: Commonly estimated residential intervention-outcome associations substantially overestimate true effects. Our somewhat paradoxical conclusion is that to estimate residential effects, investigators critically need information on nonresidential places visited.
Keywords
Self-rated Health; Record Cohort; Physical-activity; Transportation Modes; Built Environment; Activity Spaces; Research Agenda; Risk-factors; Associations; Exposure
Nazari, Ahad; Vandadian, Shaghayegh; Abdirad, Hamid. (2017). Fuzzy AHP Model for Prequalification of Engineering Consultants in the Iranian Public Procurement System. Journal Of Management In Engineering, 33(2).
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Abstract
Prequalification of engineering consultants in the Iranian public procurement system is suffering from arbitrary processes and criteria that cannot effectively shortlist the increasing number of potential bidders. This study aims to develop a prequalification model that can serve as the basis for revising the existing regulations and criteria. The authors conducted interviews among experts to localize a framework of prequalification criteria. Fuzzy analytical hierarchy process (FAHP), accompanied by a survey among industry participants, was used to determine the importance level of decision criteria. The results confirmed that the existing guidelines cannot meet the expectations of the industry due to the overemphasis on the past performance of consultants and disregarding their current capabilities. For the international audience, this study clarifies that (1)the working culture of industry participants impacts their judgments on the importance level of intangible and tangible criteria used for prequalification processes, (2)short-listing consultants for long-term and fragmented data collection in national registration or project prequalification should be avoided, and (3)researchers must test FAHP models with different fuzzy scales because the success of the widely used fuzzy extent analysis method is highly dependent on the scale of fuzzy functions and judgments of decision makers.
Keywords
Analytic Hierarchy Process; Fuzzy Set Theory; Organisational Aspects; Procurement; Project Management; Public Relations; Tendering; Fuzzy Ahp Model; Project Prequalification Criteria; Iranian Public Procurement System; Bidders; Fuzzy Analytical Hierarchy Process; Industry Participants; International Audience; National Registration; Fuzzy Scales; Fuzzy Extent Analysis Method; Decision Makers; Engineering Consultants; Working Culture; Decision-making Model; Extent Analysis Method; Selection; Qualification; Contractors; Criteria; Consultants; Prequalification; Fuzzy; Analytical Hierarchy Process (ahp)
Chen, Peng; Sun, Feiyang; Wang, Zhenbo; Gao, Xu; Jiao, Junfeng; Tao, Zhimin. (2018). Built Environment Effects on Bike Crash Frequency and Risk in Beijing. Journal Of Safety Research, 64, 135 – 143.
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Abstract
Introduction: Building a safe biking environment is crucial to encouraging bicycle use. In developed areas with higher density and more mixed land use, the built environment factors that pose a crash risk may vary. This study investigates the connection between biking risk factors and the compact built environment, using data for Beijing. Method: In the context of China, this paper seeks to answer two research questions. First, what types of built environment factors are correlated with bike-automobile crash frequency and risk? Second, how do risk factors vary across different types of bikes? Poisson lognormal random effects models are employed to examine how land use and roadway design factors are associated with the bike-automobile crashes. Results: The main findings are: (1) bike-automobile crashes are more likely to occur in densely developed areas, which is characterized by higher population density, more mixed land use, denser roads and junctions, and more parking lots; (2) areas with greater ground transit are correlated with more bike-automobile crashes and higher risks of involving in collisions; (3) the percentages of wider streets show negative associations with bike crash frequency; (4) built environment factors cannot help explain factors contributing to motorcycle-automobile crashes. Practical Applications: In China's dense urban context, important policy implications for bicycle safety improvement drawn from this study include: prioritizing safety programs in urban centers, applying safety improvements to areas with more ground transit, placing bike-automobile crash countermeasures at road junctions, and improving bicycle safety on narrower streets. (C) 2018 National Safety Council and Elsevier Ltd. All rights
Keywords
Motorcycling Accidents; Built Environment; Motorcycling; Poisson Distribution; Safety; Beijing (china); Bike-automobile Crash; Frequency; Poisson Lognormal Random Effects Model; Risk; Signalized Intersections; Transportation Modes; Urban Intersections; Bicycle Crashes; Motor-vehicle; Riders; Infrastructure; China; Severity; Frequency Distribution; Risk Factors; Bicycles; Fatalities; Collisions; Traffic Accidents; Safety Programs; Urban Environments; Traffic Safety; Population Density; Crashes; Streets; Environmental Effects; Environmental Engineering; Roads; Land Use; Risk Analysis; Urban Areas; Road Design; Construction; Ecological Risk Assessment; Design Factors; Motorcycles; Urban Transportation; Studies; Safety Management; Beijing China
Mahankali, Ranjeeth; Johnson, Brian R.; Anderson, Alex T. (2018). Deep Learning in Design Workflows: The Elusive Design Pixel. International Journal Of Architectural Computing, 16(4), 328 – 340.
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Abstract
The recent wave of developments and research in the field of deep learning and artificial intelligence is causing the border between the intuitive and deterministic domains to be redrawn, especially in computer vision and natural language processing. As designers frequently invoke vision and language in the context of design, this article takes a step back to ask if deep learning's capabilities might be applied to design workflows, especially in architecture. In addition to addressing this general question, the article discusses one of several prototypes, BIMToVec, developed to examine the use of deep learning in design. It employs techniques like those used in natural language processing to interpret building information models. The article also proposes a homogeneous data format, provisionally called a design pixel, which can store design information as spatial-semantic maps. This would make designers' intuitive thoughts more accessible to deep learning algorithms while also allowing designers to communicate abstractly with design software.
Keywords
Associative Logic; Creative Processes; Deep Learning; Embedding Vectors; Bimtovec; Homogeneous Design Data Format; Design Pixel; Idea Persistence
Acolin, Arthur. (2019). Housing Trajectories of Immigrants and Their Children in France: Between Integration and Stratification. Urban Studies (sage Publications, Ltd.), 56(10), 2021 – 2039.
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Abstract
Immigrants have been found to exhibit different housing tenure patterns from the rest of the population in a number of contexts. This article tests whether observed differences in tenure in France can be explained by differences in socio-demographic characteristics or whether unexplained differences might result from housing market mechanisms that affect immigrants differentially from the rest of the population, and extends this to the second generation. The article relies on data from TeO, a survey of 21,761 persons designed to oversample and identify immigrants and their children, providing information about the outcomes of children of immigrants that is otherwise lacking in French statistics. The results indicate that while immigrants are significantly less likely to be homeowners, even after controlling for compositional difference, the gap in homeownership between the second generation and the rest of the population is smaller and not statistically significant. This suggests a progressive integration in the housing market over time and over generations rather than overall stratified housing trajectories. Differences in terms of the share of social housing residents, the level of residential crowding, and housing and neighbourhood characteristics also decline across generations. However, children of immigrants from some non-European origins are experiencing higher levels of stratification than other groups, with continued significant differences in tenure.
Keywords
Immigrants; Housing; Home Ownership; Children Of Immigrants; Housing Market; Social Stratification; France; Homeownership; Housing Trajectories; Tenure; Segmented Assimilation; Location Choices; Wealth; 2nd-generation; Discrimination; Segregation; Inequality; Quality; Markets; Demographics; Homeowners; Neighborhoods; Crowding; Statistical Analysis; Residential Patterns; Children; Trajectories; Residents; Residential Areas; Integration; Statistics; European Cultural Groups; Sociodemographics; Stratification; Demographic Aspects; Second Generation; Property; Public Housing; Noncitizens
Idziorek, Katherine; Chalana, Manish. (2019). Managing Change: Seattle’s 21st Century Urban Renaissance. Journal Of Urbanism, 12(3), 320 – 345.
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Abstract
Evolution of the urban planning and historic preservation disciplines has resulted in an “uneasy alliance” in practice, one further complicated by the back-to-the-city movement and increased development pressure in older urban neighbourhoods. In Seattle, as in other U.S. cities, the pace, intensity and scale of redevelopment has caused dramatic spatial and social transformations. Although research has shown that older built fabric provides economic and social benefit for cities, neither regulations created by planners for guiding redevelopment nor strategies created by preservationists for retaining urban heritage have been successful in reconciling these different, yet interconnected, sets of values. We engage three Seattle neighbourhood case studies to clarify and evaluate policies, programs and strategies used by planners and preservationists for reimagining neighbourhood transformations. This work suggests a need for more creative, integrative collaboration between the two fields to simultaneously engage – and reconcile – social and economic tensions caused by urban redevelopment.
Keywords
Renaissance; Urban Planning; Biological Evolution; Historic Preservation; Seattle (wash.); Everyday Heritage; Seattle; Urban Conservation; Urban Renaissance; Redevelopment; Change Management; Neighborhoods; Regulation; Urban Renewal; Transformations; Cities; Preservation; Urban Areas; Planners; 21st Century; Cultural Heritage
Park, Kyungmo; Lee, Hyun Woo; Choi, Kunhee; Lee, Seung-hyun. (2019). Project Risk Factors Facing Construction Management Firms. International Journal Of Civil Engineering, 17(3), 305 – 321.
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Abstract
Very little is known about the project risk factors that affect construction management (CM) firms, which often struggle due to a lack of effective risk management practices. This study investigates the risk factors critical to project execution in CM firms and ranks them using the analytic hierarchy process (AHP) and failure mode and effects analysis (FMEA) methods. Interviews with executives at the top 15 Korean CM firms are carried out to identify major risk factors in the CM sector, and a survey is used to develop priority ranking. We find that payment delays and project delays are the two most critical risk factors affecting CM firms because of (1) lack of communication between headquarters and field offices, (2) shift of responsibility from headquarters to a field office, (3) absence of regular monitoring of project progress, and (4) ex-post management practices. The findings presented in this study should assist CM firms in establishing more robust risk management practices, thereby improving firms' profitability, project performance, and customer satisfaction.
Keywords
Analytic Hierarchy Process; Customer Satisfaction; Factor Analysis; Risk Assessment; Risk Management; Analytic Hierarchy Process (ahp); Construction Management; Construction Management Firms; Failure Mode And Effects Analysis; Korea; Management Practices; Risk Factors; Risk Management Practices; Industry
Acolin, Arthur. (2020). Owning vs. Renting: The Benefits of Residential Stability? Housing Studies, 37(4), 644-647.
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Abstract
In housing research, owning, as compared to renting, is generally depicted as more desirable and associated with better outcomes. This paper explores differences in outcomes between owners and renters in 25 European countries and whether these differences are systematically smaller in countries in which owners and renters have more similar levels of residential stability (smaller tenure length gap). The results indicate that the direction of the relationship between tenure type and the selected outcomes is largely similar across countries. Owners generally exhibit more desirable outcomes (including life satisfaction, civic participation, educational outcomes for children, and physical and mental health). However, when looking at the relationship between outcomes and country level differences in tenure length gap, findings suggest that renters have outcomes that are more similar to owners in countries in which tenure length gaps are smaller. These results point to the potential benefits of policies that would increase residential stability, particularly for renters.
Keywords
European Union; Homeownership Benefits; Length Of Residence; Tenure; Home-ownership; Homeownership
Hou, Jeffrey. (2020). Governing Urban Gardens for Resilient Cities: Examining the ‘Garden City Initiative’ in Taipei. Urban Studies (Sage Publications, Ltd.), 57(7), 1398 – 1416.
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Abstract
With rising concerns for food security and climate adaptation, urban gardening and urban agriculture have emerged as a rising agenda for urban resilience around the world. In East Asia, a variety of initiatives have emerged in recent years with different levels of institutional support. Focusing on Taipei, where a vibrant urban agriculture movement has been unleashed in recent years, this article examines the ongoing outcomes of the city's new 'Garden City Initiative', which supports the establishment of urban gardens including community gardens, rooftop gardens and school gardens. Based on interviews and participant observations during the initial period of advocacy, planning and implementation between 2014 and 2017, this study examines the background of the programme, the involvement of governmental and non-governmental actors and the programme's ongoing implementation. Based on the findings, the article further reflects upon their implications for the practices of urban governance in the face of contemporary environmental, political and social challenges. The case of Taipei suggests a model in which policy formation and implementation may require opportunistic actions involving a variety of actors and organisations in both institutions and the civil society. Rather than dramatic changes or instant institutional realignment, the effort may require strategic adaptation of the existing bureaucratic structure, while mobilising its strengths and resources. In addition, despite the critical role of civil society organisations, the Taipei case also illustrates a considerable public-sector investment, distinct from the predominant model of neoliberal governance that has been associated with urban gardening programmes elsewhere.
Keywords
Urban Gardening; Urban Planning; Sustainability; Urban Agriculture; Local Government; Taipei (taiwan); 地方政府; 城市农业; 城市田园; 政策; 治理; 环境/可持续性; 规划; Environment/sustainability; Governance; Planning; Policy; Urban Gardens; Community Gardens; Food; Agriculture; Space; Inclusion; Systems; Environment; Realignment; Intervention; Social Change; Food Security; Civil Society; Initiatives; Gardens & Gardening; Policy Making; Neoliberalism; Resilience; Urban Farming; Gardening; Advocacy; Implementation; Roofs; Cities; Adaptation; Urban Areas; Gardens; Institutional Aspects; Bureaucracy; Policy Implementation; Environmental Policy; Climate Change Adaptation; Taipei Taiwan; Taiwan