DOI: 10.5061/dryad.bvq83bkd4
title: Measures of urban form and mobility energy use indices for each census tract in the United States

description: This dataset contains data on urban form (the configuration of the built
 environment) for each census tract in the United States, encompassing
 density (destination access), land use diversity (entropy), road network
 properties, road network capacity relative to the surrounding population,
 and public transit access. Metrics are measured around the centroid of
 each census tract in multiple given radii. The data also contain other
 publicly available metrics for each census tract that may be helpful, such
 as each tract's associated city, zipcode, and county name, area and
 water area, and centroid coordinates. Certain measures resemble those
 available in the U.S. Environmental Protection Agencies' Smart
 Location database or were derived from them, while others were compiled
 using additional data sources and the statistical model presented in the
 associated main article. Specifically, the data presented here contain
 travel energy use indices for each census tract, reflecting the estimated
 difference in daily land-based mobility energy use per capita relative to
 the baseline (the U.S. average) as a result of that environment's
 particular urban form. 
description: General description Each urban form metric
 is first estimated at the level of the census block group (CBG). Those
 values are then aggregated to the census tract (CT) level, where each CT
 consists of 2-4 CBGs. This is done because geographical locations in the
 national household travel survey (NHTS), which this dataset has been
 designed to be merged with, are available specifically at the CT level. We
 measure all properties of urban form in a given constant radius around
 each CBG. Since CBGs and CTs are defined such that they contain a
 relatively constant residential population, they are smaller in dense
 areas than in low-density areas. Therefore, the effective spatial
 resolution of our analysis is higher in areas with a higher residential
 population density compared to lower-density areas and/or areas with
 commercial or industrial activity but fewer residents.
 We measure urban form in five sets: destination density (the
 number of destinations accessible at certain distance intervals), land use
 entropy, access to public transit stops, road network properties, and road
 network capacity. These metrics are taken or derived from the U.S.
 Environmental Protection Agencies Smart Location (SL) database,
 complemented with information from OpenStreetMap (accessed using OSMnx,
 https://github.com/gboeing/osmnx). In Table S2 of the Supplementary Material of the associated article, we provide a detailed comparison between the measured urban form contained in the SL database and our measures, along with reasons for potential differences and additions. List of all available columns The file <em>fields.csv</em> included in this resource lists each data column available in the main data file, along with a brief description, the source of the original data that the indicator has been derived from, and a flag showing whether this indicator is used in the final model of the article that is associated with this dataset. A more detailed description of how each indicator was determined can also be found in the Supplementary Material of the associated article. Energy use indices and their interpretation The final set of indicators in the data file contains the travel energy use indices for each census tract. These indices reflect the estimated difference in daily mobility energy use for land-based travel per capita relative to the baseline (the U.S. average) as a result of that environment's particular urban form and are based on the fitted statistical coefficients of the model presented in the associated main article. They are unitless and relative in nature. For two different regions (e.g., census tracts or places) <em>0</em> and <em>1</em>, the estimated difference in daily mobility energy use between those two places due to differences in urban form, in percent, is: exp(eindex_0 - eindex_1) x 100 - 100 For example, if location <em>0</em> has an energy index value of -0.287, and location <em>1</em> has a value of 0.008, we estimate that the difference in daily average energy use for land-based mobility between location <em>0</em> and <em>1</em> is exp(-0.287-0.008)*100-100 = -25.5 (25.5% lower in location <em>0</em> than in location <em>1</em>). Energy indices can be averaged over larger areas (e.g. across all census tracts in a given place) and are cumulative (e.g., the road network index can be combined with the access index).
description: The data is available as comma-separated-value (CSV) files and
 can be opened with any appropriate software.