Categories
Urban

Scaling Urban Indicators

I have a new article out now in the journal of Urban Policy and Research coauthored with a team comprising many of the folks from our recent series in The Lancet Global Health. The article is titled “Policy-Relevant Spatial Indicators of Urban Liveability and Sustainability: Scaling from Local to Global” and discusses measuring urban indicators and scaling the software to calculate them from a local case study to a worldwide effort.

From the abstract:

Urban liveability is a global priority for creating healthy, sustainable cities. Measurement of policy-relevant spatial indicators of the built and natural environment supports city planning at all levels of government. Analysis of their spatial distribution within cities, and impacts on individuals and communities, is crucial to ensure planning decisions are effective and equitable. This paper outlines challenges and lessons from a 5-year collaborative research program, scaling up a software workflow for calculating a composite indicator of urban liveability for residential address points across Melbourne, to Australia’s 21 largest cities, and further extension to 25 global cities in diverse contexts.

For more, check out the article itself. And you may also be interested in our recent The Lancet Global Health series of articles that developed similar themes in great depth.

Categories
Planning

Two-Way Streets and Network Efficiency

I have a new article out now in the Journal of Planning Education and Research with Billy Riggs, in which we examine how two-way street conversions impact street network efficiency. Most of the efficiency literature looks at the benefits of one-way streets for signalization and vehicular throughput. We took a different approach, considering how one-way streets inherently increase travel distances.

Categories
Urban

The Lancet Global Health Series on Urban Design, Transport, and Health

After many years of hard work, our series of articles on urban design, transport, and health has been published by The Lancet Global Health.

The Lancet Global Health infographic on benchmarking healthy sustainable citiesIn our first paper, we analyzed urban policies and calculated built environment indicators for 25 cities across 6 continents to assess walkability and accessibility. Our policy analysis found policies inconsistent with public health evidence, rhetoric endorsing health and sustainability but few measurable policy targets, and substantial implementation gaps.

Categories
Urban

Housing Tech and Tilted Platforms

I have a new article out now in a special issue on platform urbanism, co-authored with Max Besbris, David Wachsmuth, and Jake Wegmann, titled Tilted Platforms: Rental Housing Technology and the Rise of Urban Big Data Oligopolies. We reflect on short-term and long-term rental housing technologies and how they’re affecting the housing search, equity, and affordability.

From the abstract:

This article interprets emerging scholarship on rental housing platforms—particularly the most well-known and used short- and long-term rental housing platforms—and considers how the technological processes connecting both short-term and long-term rentals to the platform economy are transforming cities. It discusses potential policy approaches to more equitably distribute benefits and mitigate harms. We argue that information technology is not value-neutral. While rental housing platforms may empower data analysts and certain market participants, the same cannot be said for all users or society at large. First, user-generated online data frequently reproduce the systematic biases found in traditional sources of housing information. Evidence is growing that the information broadcasting potential of rental housing platforms may increase rather than mitigate sociospatial inequality. Second, technology platforms curate and shape information according to their creators’ own financial and political interests. The question of which data—and people—are hidden or marginalized on these platforms is just as important as the question of which data are available. Finally, important differences in benefits and drawbacks exist between short-term and long-term rental housing platforms, but are underexplored in the literature: this article unpacks these differences and proposes policy recommendations.

For more, check out the article.

Categories
Planning

Framework for Measuring Pedestrian Accessibility

I’m a co-author of a new article, “A Generalized Framework for Measuring Pedestrian Accessibility around the World Using Open Data,” which has just been published by Geographical Analysis. We developed an open source, containerized software framework for modeling pedestrian networks using open data to analyze disaggregate access to daily living needs. We worked with local partners in 25 cities around the world to demonstrate and validate this toolkit.

From the abstract:

Pedestrian accessibility is an important factor in urban transport and land use policy and critical for creating healthy, sustainable cities. Developing and evaluating indicators measuring inequalities in pedestrian accessibility can help planners and policymakers benchmark and monitor the progress of city planning interventions. However, measuring and assessing indicators of urban design and transport features at high resolution worldwide to enable city comparisons is challenging due to limited availability of official, high quality, and comparable spatial data, as well as spatial analysis tools offering customizable frameworks for indicator construction and analysis. To address these challenges, this study develops an open source software framework to construct pedestrian accessibility indicators for cities using open and consistent data. It presents a generalized method to consistently measure pedestrian accessibility at high resolution and spatially aggregated scale, to allow for both within- and between-city analyses. The open source and open data methods developed in this study can be extended to other cities worldwide to support local planning and policymaking. The software is made publicly available for reuse in an open repository.

For more, check out the article.

Categories
Planning

Robert Moses Responds to Robert Caro

In 1974, Robert Caro published The Power Broker, a critical biography of Robert Moses’s dictatorial tenure as the “master builder” of mid-century New York. Moses profoundly transformed New York’s urban fabric and transportation system, producing the Brooklyn Battery Tunnel, the Verrazano Narrows Bridge, the Westside Highway, the Cross-Bronx Expressway, the Lincoln Center, the UN headquarters, Shea Stadium, Jones Beach State Park and many other projects. However, The Power Broker did lasting damage to his public image and today he remains one of the most controversial figures in city planning history.

Today, The Power Broker may be the most well-known biography of any urban planner ever. Less-known: on August 26, 1974, Moses issued a turgid 23-page statement denouncing Caro’s work as “full of mistakes, unsupported charges, nasty baseless personalities, and random haymakers.” Moses’s original typewritten statement survives today as a grainy photocopy in the New York City Parks Department archive. To better preserve and disseminate it, I extracted and transcribed its text using optical character recognition and edited the result to correct errors. My transcription of Moses’s statement, alongside Caro’s response to it, is available here.

Categories
Urban

Urban Form and OpenStreetMap

My chapter “Exploring Urban Form Through OpenStreetMap Data: A Visual Introduction” has just been published in the new book Urban Experience and Design: Contemporary Perspectives on Improving the Public Realm edited by Justin Hollander and Ann Sussman.

From the abstract:

This chapter introduces OpenStreetMap—a crowdsourced, worldwide mapping project and geospatial data repository—to illustrate its usefulness in quickly and easily analyzing and visualizing planning and design outcomes in the built environment. It demonstrates the OSMnx toolkit for automatically downloading, modeling and visualizing spatial data from OpenStreetMap. We explore patterns and configurations in street networks and buildings around the world computationally through visualization methods—including figure-ground diagrams and polar histograms—that help compress urban complexity into comprehensible artifacts that reflect the human experience of the built environment. Ubiquitous urban data and computation can open up new urban form analyses from both quantitative and qualitative perspectives.

For more, check out the chapter.

Categories
Planning

Off the Grid… and Back Again?

My article “Off the Grid… and Back Again? The Recent Evolution of American Street Network Planning and Design” has been published by the Journal of the American Planning Association and won the 2020 Stough-Johansson Springer Award for best paper. It identifies recent nationwide trends in American street network design, measuring how urban planners abandoned the grid and embraced sprawl over the 20th century, but since 2000 these trends have rebounded, shifting back toward historical design patterns. In this post I discuss these findings and visualizations across the US today as well as over time, then discuss my analysis methods.

Map of where street grids exist today across the US, made with OSMnx and Python

Categories
Planning

Off the Grid at TRB

I am presenting my ongoing research into the recent evolution of American street network planning and design at the annual meeting of the Transportation Research Board in Washington DC on January 13. This presentation asks the question: how has street network design changed over time, especially in recent years? I analyze the street networks of every US census tract and estimate each’s vintage.

Street network designs grew more disconnected, coarse-grained, and circuitous over the 20th century… but the 21st century has witnessed a promising rebound back toward more traditional, dense, and interconnected grids. Higher griddedness is associated with less car ownership, even when controlling for related socioeconomic, topographical, and other urban factors.

Update: the paper has been published in JAPA.

Categories
Urban

Big Data in Urban Morphology

My new article “Spatial Information and the Legibility of Urban Form: Big Data in Urban Morphology” has been published in the International Journal of Information Management (download free PDF). It builds on recent work by Crooks et al, presenting workflows to integrate data-driven and narrative approaches to urban morphology in today’s era of ubiquitous urban big data. It situates this theoretically in the visual culture of planning to present a visualization-mediated interpretative process of data-driven urban morphology, focusing on transportation infrastructure via OSMnx.

OSMnx: Figure-ground diagrams of one square mile of each street network, from OpenStreetMap, made in Python with matplotlib, geopandas, and NetworkX