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How walkable is your neighborhood? Assessing walkability around T-stops outside the city of Boston
Conclusions
Methodology
Findings
Limitations
Background
Data Sources
First, roads one mile within each T-
stop were selected from the
MassGIS Mass Department of
Transportation (DOT) Roads dataset
using the “Select by Location” tool.
T-stops in Boston and Brookline
were excluded by deselecting roads
with a city code of “35” or “46” .
The remaining roads were exported
into a new file and the attributes ta-
ble was imported into SAS. SAS
was used to create scores for various
components within the dataset to
compute a walkability score. Any
road with missing data was excluded
from the total score.
Right side walk and left side walk
were both categorized as follows: 0,
greater than 0 but less than five feet
wide, equal to five feet wide, and
greater than five feet wide, and as-
signed a score of 0, 1, 2, or 3, respec-
tively. Road type was categorized us-
ing the Functional Classification as
follows: Interstate, Urban or Rural
Principal Arterial, Rural Minor Arte-
rial; Urban Minor Arterial or Rural
Major Collector; Urban Collector or
Rural Minor Collector; and Local,
and assigned a score of 0, 1, 2, or 3,
respectively. Right Shoulder Type
was categorized as having a shoulder
or no shoulder, and assigned a score
of 0 or 3 respectively. Left shoulder
type could not be used, as 85% of the
variable was missing. Terrain was
categorized as Mountainous, Rolling,
and Level, and scored as 0, 1, and 2,
respectively. Finally, curbs were
classified as no curb or median only,
left or right side only, or all sides, and
scored as 0, 1, and 2, respectively.
The scores from each component were
averaged together. The new variables
created were then imported back to
ArcGIS and joined to the MassDOT
Roads shape file. Then, a total score
for each T-stop was created by select-
ing the T-stop of interest, using the
“Select by Location” tool to select
roads within 1 mile of the selected T-
stop, and summing the scores for all
roads selected. The average score per
road for each T-stop was calculated by
dividing the total score by the count of
roads. Finally, the percent of missing
data was calculated.
Table 1 presents the T-stop, train line,
Walkability Score, number of observa-
tions, the percent missing, and the walka-
bility per road. Many T-stops had over
fifty percent of data missing (Braintree,
Rivreside, Woodland, Waban, Chestnut
Hill). According the data and scoring
method, the areas with the highest walka-
bility per count were along the red line,
and included Porter Square, Davis
Square, Harvard Square, and Kendall/
MIT. These areas also tended to have the
lowest percentages of missing data. The
areas with the lowest walkability per
count were Riverside, Chestnut Hill,
Woodland, and Waban. These areas also
tended to have the highest percentages of
missing data. It is unknown how the miss-
ing would have affected the direction of
the scores. For illustrative purposes,
each map shows each score component
comparing the Alewife stop to the Davis
Square stop. Based on the data and on
the scoring system, it could be concluded
that Davis Square is more walkable than
Alewife.
Walkability was only assessed using
one data source, the MassGIS
MassDOT Roads dataset. Each vector
was assumed to be homogenous.
Sidewalks were only included if asso-
ciated with a road in the dataset.
Other potential contributors to walka-
bility, such as distance to businesses,
lighting, land use diversity, and crime
rates were not included. Results have
not been validated against other walk-
ability scores or against surveys
measuring perception of walkability.
Of the variables of interest, the da-
taset had a high proportion missing,
ranging between 18% and 59%.
Walkability can be defined as the
overall walking conditions and indi-
viduals who live in more walkable
areas tend to report being healthier
(Oishi et al). Walkability is especially
important in New England, as heavy
snow can narrow sidewalks.
Past walk scores have included resi-
dential density score, street connec-
tivity score, and a land use mix score
(Sundquist et al). These calculated
scores can validated by comparing to
surveys measuring perception of
walkability, or by accelerometer use.
The purpose of this project was to de-
velop a measure of walkability using
variables considered to reflect
walkability in the MassGIS
MassDOT Roads dataset and compare
scores among various T-stops outside
the city of Boston.
MassGIS Data – Massachusetts Department of Transportation
(MassDOT) Roads, June 2014; MassDOT and MassGIS,
published by MassGIS, accessed November 6, 2015.
MassGIS Data – Rapid Transit, September 2014, Central Trans-
portation Planning Staff and MassGIS. Accessed November
6, 2015.
MassDEP Hydrography (1:25,000), March 2010, Massachusetts
Department of Environmental Protection and U.S. Geologi-
cal Survey (USGS)
Protected and Recreational OpenSpace, May 2015, Executive
Office of Energy and Environmental Affairs.
MassGIS Data – Community Boundaries (Towns), February
2014, USGS, Massachusetts Dept. of Public Works, and
MassGIS.
Oishi S, Saeki M, Axt J.Are People Living in Walkable Areas Healthier and More Satisfied with Life? Appl Psy-
chol Health Well Being. 2015 Nov; 7(3):365-86.
Sundquist, K., Eriksson, U., Kawakami, N., Skog, L., Ohlsson, H., Arvidsson, D. Neighborhood walkability,
physical activity, and walking behavior: The Swedish Neighborhood and Physical Activity (SNAP) study.
Cartographer: Tamar Roomian
Date: December 22, 2015
Course: Fundamentals of GIS for Food, Agriculture, and
Environmental Applications
Lecturer: Paul B. Cote
School: Gerald J. and Dorothy R. Friedman School of Nutrition
Science and Policy
Map displayed on 1:60,000 scale Map displayed on 1:25,000 scale
Map displayed on 1:25,000 scale
Map displayed on 1:25,000 scale Map displayed on 1:25,000 scale
Map displayed on 1:25,000 scale
Map displayed on 1:25,000 scale
While a score was created to compare
walkability around T-stops outside the
Boston area, given the high proportion
of missing data, results should be inter-
preted with caution. Future work may
incorporate other contributors to
walkability, such as proximity to busi-
nesses, lighting, land use diversity, and
crime rates. Future work may also vali-
date against other walkability scores,
surveys measuring perception of walka-
bility, or accelerometer use.
Table 1. Walkability Score and Walkability Score Per Road
T-stop Line Walkability Score Count % Missing Walkability/Count
Porter Red 2916 1526 17.60 1.911
Davis Square Red 2681 1406 20.25 1.907
Central Red 2350 1235 21.59 1.903
Malden Center Orange 2163 1149 28.46 1.883
Harvard Red 2250 1207 21.01 1.864
Kendall/MIT Red 1398 756 27.03 1.849
Oak Grove Orange 1452 786 45.87 1.847
Sullivan Square Orange 1124 617 34.92 1.822
Assembly Orange 1056 595 42.06 1.775
Alewife Red 1496 849 27.25 1.762
Revere Beach Blue 916 525 40.27 1.745
Wonderland Blue 919 533 37.88 1.724
Quincy Center Red 1304 757 32.41 1.723
Wellington Orange 896 523 44.06 1.713
Beachmont Blue 552 326 46.47 1.693
Newton Highlands Green 1143 679 40.75 1.683
Eliot Green 1028 617 42.71 1.666
North Quincy Red 1183 715 23.37 1.655
Braintree Red 531 324 60.77 1.639
Quincy Adams Red 907 557 43.79 1.628
Wollaston Red 1492 924 18.30 1.615
Newton Centre Green 1098 682 40.64 1.610
Waban Green 687 435 52.15 1.579
Woodland Green 611 402 54.78 1.520
Chestnut Hill Green 398 277 57.77 1.437
Riverside Green 554 404 58.61 1.371