Skip to content

First-Time Homebuyers: Toward a New Measure

Acolin, Arthur; Calem, Paul; Jagtiani, Julapa; Wachter, Susan. (2018). First-Time Homebuyers: Toward a New Measure. Cityscape, 20(1), 193 – 204.

View Publication

Abstract

Existing data sources show divergent estimates of the number of homes purchased by first-time homebuyers as a share of all home purchases. In this article, we use a new dataset to construct a time series of the share of first-time homebuyers. This series, based on the Federal Reserve Bank of New York Equifax Consumer Credit Panel, shows a significant decline in the share of first-time homebuyers, particularly among young households, consistent with the decline in homeownership in this age cohort since the early 2000s.

Who Owns Chinatown: Neighbourhood Preservation and Change in Boston and Philadelphia

Acolin, Arthur; Vitiello, Domenic. (2018). Who Owns Chinatown: Neighbourhood Preservation and Change in Boston and Philadelphia. Urban Studies, 55(8), 1690 – 1710.

View Publication

Abstract

The survival of Chinatowns and other ethnic enclaves in cities is largely determined by who owns property. Ethnic enclaves such as Chinatowns have traditionally played important economic, social and cultural functions as places for recent immigrants to live and work, though Chinatowns have long faced redevelopment pressures. In North America, as Chinese immigrants and their descendants settle in the suburbs, and as historic Chinatowns’ locations close to revitalising downtowns attract increasing investment, the future of these historic enclaves is shaped by various, often intense and divergent, forces. This article describes changes in the patterns of property ownership in Boston and Philadelphia’s downtown Chinatowns over the last decade (2003–2013) and relates them to changes and continuities in these neighbourhoods’ population, commercial activities and building stock. The trends we observe simultaneously reinforce and complicate debates about gentrification and longstanding efforts to preserve these Chinatowns as ethnic Chinese residential, commercial, and cultural centres.]

Keywords

Chinatown, Ethnic Enclave, Neighbourhood Change, Ownership

Motivations to Prepare After the 2013 Cook Strait Earthquake, N.Z.

Doyle, Emma E. H.; Mcclure, John; Potter, Sally H.; Becker, Julia S.; Johnston, David M.; Lindell, Michael K.; Johal, Sarbjit; Fraser, Stuart A.; Coomer, Maureen A. (2018). Motivations to Prepare After the 2013 Cook Strait Earthquake, N.Z. International Journal Of Disaster Risk Reduction, 31, 637 – 649.

View Publication

Abstract

We investigated responses to the 2013 Cook Strait earthquake sequence, New Zealand. This included two foreshocks (M5.7 and M5.8) and a mainshock doublet pair: M6.5 Cook Strait (CS) earthquake on 21st July and M6.6 Lake Grassmere (LG) earthquake on Friday 16th August. We examined relationships between preparedness, experience and beliefs during the earthquakes, as well as concern and subsequent preparedness actions. Results indicate that earthquake characteristics (e.g., time, location) influence the types of preparedness actions. While there was a reduction in new actions from the first mainshock doublet earthquake (CS) to the second (LG), there were a large number of participants who reviewed or revisited their prior actions, related to their beliefs about impacts, in a form of problem-focused targeted action. Females took more actions than did males, and had a higher rate of immediate aftershock concern. For all participants, concern was greater after the CS earthquake than after the full earthquake sequence, supporting the findings of McClure et al. (2016) that there is a limited window after an event to maximise the opportunity for effective preparedness initiatives. Findings additionally suggest that such post-earthquake preparedness initiatives should consider the impacts that elicited the highest rate of concern in an event, and should tailor messages towards them. While this earthquake sequence resulted in low levels of impact and damage, it presents interesting findings regarding how disruption (in lieu of major damage) influences earthquake preparedness actions, which is particularly important to understand in highly active regions often exposed to smaller impact events.

Keywords

Seismic Hazard Adjustments; Risk Communication; Decision-making; Natural Hazards; Unrealistic Optimism; Different Regions; Volcanic Crisis; Perception; Disaster; Behavior; Earthquakes; Preparedness; Beliefs; Concern; Actions; Gender

Training Of Low-literacy And Low-english-proficiency Hispanic Workers On Construction Fall Fatality

Lin, Ken-yu; Lee, Wonil; Azari, Rahman; Migliaccio, Giovanni C. (2018). Training Of Low-literacy And Low-english-proficiency Hispanic Workers On Construction Fall Fatality. Journal Of Management In Engineering, 34(2).

View Publication

Abstract

The construction industry has made extensive efforts to improve the safety of its labor force through various approaches, including training. However, many construction workers in the United States are recent immigrants who lack English proficiency and do not possess sufficient literacy levels in their own language for training comprehension. This reduces the effectiveness of traditional text-dominated translated training materials, which depend on both literacy and proficiency in a language. Thus, in this study, the authors used three-dimensional (3D) visualization to overcome the communication barriers that hinder effective safety training for low-literacy (LL) and low-English-proficiency (LEP) construction workers. This article summarizes the contributions of a study sponsored by the Occupational Safety and Health Administration (OSHA) Susan Harwood Training Grant Program; it describes the methodology to develop scenario-based 3D training materials on fall safety for LL and LEP workers and to validate the effectiveness of the materials. The results show that 3D training materials improve interaction between trainer and trainee during safety training, facilitate learning processes, and can overcome some of the communication barriers that hinder effective safety training. (c) 2017 American Society of Civil Engineers.

Keywords

Chemical Hazards; Computer Based Training; Construction Industry; Hazardous Materials; Industrial Training; Occupational Health; Occupational Safety; Personnel; Safety; Low-literacy; Low-english-proficiency Hispanic Workers; Construction Fall Fatality; Extensive Efforts; Labor Force; Construction Workers; English Proficiency; Sufficient Literacy Levels; Training Comprehension; Training Materials; Three-dimensional Visualization; Communication Barriers; Effective Safety Training; Health Administration Susan Harwood Training Grant Program; Fall Safety; Occupational Injuries; United-states; Industry; Health; Education; Issues; Occupational Health And Safety; Training; Visualization; Fall Protection; Case Study

Six Fundamental Aspects for Conceptualizing Multidimensional Urban Form: A Spatial Mapping Perspective

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.

View Publication

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

A New Method to Visualize Obesity Prevalence in Seattle-King County at the Census Block Level

Drewnowski, A.; Buszkiewicz, J.; Aggarwal, A.; Cook, A.; Moudon, A. V. (2018). A New Method to Visualize Obesity Prevalence in Seattle-King County at the Census Block Level. Obesity Science & Practice, 4(1), 14 – 19.

View Publication

Abstract

Objective The aim of this study is to map obesity prevalence in Seattle King County at the census block level. Methods Data for 1,632 adult men and women came from the Seattle Obesity Study I. Demographic, socioeconomic and anthropometric data were collected via telephone survey. Home addresses were geocoded, and tax parcel residential property values were obtained from the King County tax assessor. Multiple logistic regression tested associations between house prices and obesity rates. House prices aggregated to census blocks and split into deciles were used to generate obesity heat maps. Results Deciles of property values for Seattle Obesity Study participants corresponded to county-wide deciles. Low residential property values were associated with high obesity rates (odds ratio, OR: 0.36; 95% confidence interval, CI [0.25, 0.51] in tertile 3 vs. tertile 1), adjusting for age, gender, race, home ownership, education, and incomes. Heat maps of obesity by census block captured differences by geographic area. Conclusion Residential property values, an objective measure of individual and area socioeconomic status, are a useful tool for visualizing socioeconomic disparities in diet quality and health.

Keywords

Residential Property-values; Socioeconomic-status; Health; Environment; Adults; Census Block; Geographic Information Systems; Mapping Obesity; Ses Measures

Parking Policies in China’s Metropolises: Rationales, Consequences, and Implications

Liu, Qian; Chen, Peng; Sun, Feiyang. (2018). Parking Policies in China’s Metropolises: Rationales, Consequences, and Implications. Urban Policy & Research, 36(2), 186 – 200.

View Publication

Abstract

Metropolises in China, a rapidly motorizing nation, are confronted with the challenge of managing parking pressures. Given the generally increased affordability of cars, most local authorities are making efforts to provide more parking spaces to accommodate additional cars. Although the worldwide paradigm of managing parking is shifting from a supply-focused approach to a restraint mind-set, China has been slow to follow this trend. To untangle the factors that contribute to delays implementing desirable parking policy reforms, this paper examines the development of parking policies in China. This paper characterizes the challenge of parking in Chinese cities as a spatio-temporal mismatch. In the context of rapid motorization, local authorities are subject to political pressure to cater to the increased parking demand by increasing the minimum parking requirements. However, this approach fails to mitigate parking shortages and results in unintended consequences, including relatively high parking density in central and transit-rich areas and imbalanced parking across neighbourhoods. This paper suggests four strategies, including market-based pricing, geographically differentiated supply regulations, and district-based parking management (Parking management is referred to as various policies and programs that result in more efficient use of parking resources). These strategies represent policy-reform targets to establish more efficient parking systems in rapidly motorizing urban settings worldwide.

Keywords

Parking Facilities; Urbanization; Parking Lots; China; Minimum Parking Requirements; Motorization; Parking Policies; Parking Supply; Spatio-temporal Mismatch; Requirements; Minimum; Ownership; Future; Transportation; Cities; Pressure; Neighborhoods; Affordability; Local Authorities; Shortages; Regulation; Developmental Delays; Density; Parking; Reforms

Is There a Limit to Bioretention Effectiveness? Evaluation of Stormwater Bioretention Treatment Using a Lumped Urban Ecohydrologic Model and Ecologically Based Design Criteria

Wright, Olivia M.; Istanbulluoglu, Erkan; Horner, Richard R.; Degasperi, Curtis L.; Simmonds, Jim. (2018). Is There a Limit to Bioretention Effectiveness? Evaluation of Stormwater Bioretention Treatment Using a Lumped Urban Ecohydrologic Model and Ecologically Based Design Criteria. Hydrological Processes, 32(15), 2318 – 2334.

View Publication

Abstract

In this study, we developed the urban ecohydrology model (UEM) to investigate the role of bioretention on watershed water balance, runoff production, and streamflow variability. UEM partitions the land surface into pervious, impervious, and bioretention cell fractions. Soil moisture and vegetation dynamics are simulated in pervious areas and bioretention cells using a lumped ecohydrological approach. Bioretention cells receive runoff from a fraction of impervious areas. The model is calibrated in an urban headwater catchment near Seattle, WA, USA, using hourly weather data and streamflow observations for 3years. The calibrated model is first used to investigate the relationship between streamflow variability and bioretention cell size that receives runoff from different values of impervious area in the watershed. Streamflow variability is quantified by 2 indices, high pulse count (HPC), which quantifies the number of flow high pulses in a water year above a threshold, and high pulse range (HPR), which defines the time over which the pulses occurred. Low values of these indices are associated with improved stream health. The effectiveness of the modelled bioretention facilities are measured by their influence on reducing HPC and HPR and on flow duration curves in comparison with modelled fully forested conditions. We used UEM to examine the effectiveness of bioretention cells under rainfall regimes that are wetter and drier than the study area in an effort to understand linkages between the degree of urbanization, climate, and design bioretention cell size to improve inferred stream health conditions. In all model simulations, limits to the reduction of HPC and HPR indicators were reached as the size of bioretention cells grew. Bioretention was more effective as the rainfall regime gets drier. Results may guide bioretention design practices and future studies to explore climate change impacts on bioretention design and management.

Keywords

Performance Assessment; Hydrologic Alteration; Automated Techniques; Management-practices; Land-cover; Streams; Water; Impact; Area; Runoff; Bioretention; Ecohydrology; Green Infrastructure; Stormwater; Stream Health; Urban Hydrology; Evaluation; Urbanization; Watersheds; Soil Moisture; Water Balance; Stream Flow; Design; Variability; Ecological Monitoring; Computer Simulation; Storms; Climate Change; Duration; Water Runoff; Flow Duration Curves; Flow Duration; Cell Size; Soils; Duration Curves; Rainfall; Rivers; Cells; Headwaters; Surface Runoff; Dynamics; Rainfall Regime; Catchment Area; Design Criteria; Environmental Impact; Retention Basins; Soil Dynamics; Stream Discharge; Climatic Changes; Meteorological Data; Headwater Catchments

The Anthropocene Generalized: Evolution of Exo-Civilizations and Their Planetary Feedback

Frank, A.; Carroll-Nellenback, Jonathan; Alberti, M.; Kleidon, A. (2018). The Anthropocene Generalized: Evolution of Exo-Civilizations and Their Planetary Feedback. Astrobiology, 18(5), 503 – 518.

View Publication

Abstract

We present a framework for studying generic behaviors possible in the interaction between a resource-harvesting technological civilization (an exo-civilization) and the planetary environment in which it evolves. Using methods from dynamical systems theory, we introduce and analyze a suite of simple equations modeling a population which consumes resources for the purpose of running a technological civilization and the feedback those resources drive on the state of the host planet. The feedbacks can drive the planet away from the initial state the civilization originated in and into domains that are detrimental to its sustainability. Our models conceptualize the problem primarily in terms of feedbacks from the resource use onto the coupled planetary systems. In addition, we also model the population growth advantages gained via the harvesting of these resources. We present three models of increasing complexity: (1) Civilization-planetary interaction with a single resource; (2) Civilization-planetary interaction with two resources each of which has a different level of planetary system feedback; (3) Civilization-planetary interaction with two resources and nonlinear planetary feedback (i.e., runaways). All three models show distinct classes of exo-civilization trajectories. We find smooth entries into long-term, sustainable steady states. We also find population booms followed by various levels of die-off. Finally, we also observe rapid collapse trajectories for which the population approaches n=0. Our results are part of a program for developing an Astrobiology of the Anthropocene in which questions of sustainability, centered on the coupled Earth-system, can be seen in their proper astronomical/planetary context. We conclude by discussing the implications of our results for both the coupled Earth system and for the consideration of exo-civilizations across cosmic history.

Keywords

Anthropocene Epoch; Holocene Epoch; Climatology; Earth System Science; Climate Change; Earth (planet); Biosphere; Easter-island; Earth; Population; Anthropocene; Astrobiology; Civilization; Dynamical System Theory; Exoplanets; Population Dynamics

Deep Learning in Design Workflows: The Elusive Design Pixel

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.

View Publication

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