Assessing job accessibility of essential workers in Atlanta, GA Cumulative Opportunity Model
Jobs per CBG Population
Q1
Q2
Q4
Miles
0
2
Q2
Q3 Q4 Q5
Hot Spot - 99% Confidence Hot Spot - 95% Confidence
Essential Job Kernel Density
Hot Spot - 90% Confidence Not Significant
0
CCUMR60
0.15
0.50
1.00
0.95
0.91
0.64
0.75
0.50
KCUMR60
0.13
0.57
0.95
1.00
0.90
0.70
CPOWER1_0
0.77
0.69
0.91
0.90
1.00
0.86
KPOWER1_0
0.05
0.67
0.64
0.70
0.86
1.00
0.25
0.00
1 - 610
611 - 1,221
Coefficient Value = .13
1,222 - 3,052
3,053 - 155,673
Miles
0
2
4
Coefficient Value = .05 40000
250000
35000
200000
Quartile 1
Quartile 2
30000
150000
100000
50000
0 0
Quartile 3
50000
100000
150000
200000
250000
Median Household Median Household IncomeIncome
25000 20000 15000 10000
5000 0 0
Quartile 4
50000
100000
150000
200000
250000
Median Household Median Household IncomeIncome
Quartile 5
Q5
0.67
250000
Q4
0.69
200000
Coefficient Value = -.01
Accessibility Score
0.57
150000
Coefficient Value = .08
Q3
0.50
100000
Median Household Median Household Income Income
(1 mile from centroid)
Accessibility Score
1.00
50000
Straight-Line Distance
Q2
-0.01
0
Coefficient Value = .15
Q1
JobsPerPerson
250000
Accessibility Score
0.05
200000
Median Household Median Household IncomeIncome
Accessibility Score
0.77
150000
Kernel Density
0.13
100000
4
STRAIGHT-LINE DISTANCE
The cumulative opportunity models in both aggregation techniques had stronger correlations with income than the gravity models, but were still extremely weak (r2=.15 for fishnet and r2=.13 for kernel density). 0.15
50000
3,053 - 155,673
The gravity model accessibility scores had no significant correlation with income for the fishnet aggregation (r2= .08) or the kernel density aggregation (r2=.05).
-0.01
0
1,222 - 3,052
Q1
1.00
0
0
611 - 1,221
The correlation between cumulative opportunity accessibility scores and gravity scores have an extremely strong correlation (r2=.91) for the fishnet aggregation and a strong correlation for kernel density aggregation (r2=.70).
Income
500
10000
Not Significant
Jobs per CBG Population
1.00
1000
Hot Spot - 90% Confidence
We identified job locations of essential jobs according to CDC definition. The jobs were aggregated to zones identified through two aggregation techniques: a fishnet determined through the average nearest neighbor and census block groups. The opportunity of each zone was determined by the number of jobs in each zone for the fishnet and the average kernel density for each census block group. The centroids of fishnets and the census block groups were used as destinations.
FINDINGS
1500
Hot Spot - 95% Confidence
1 - 610
With GTFS data, we created a public transportation network based on travel time.Using Higgins (2019) accessibility toolbox, the accessibility scores from each census block group centroids to job locations were calculated using cumulative opportunity models and gravity models.
20000
2000
Hot Spot - 99% Confidence
0
METHODS
30000
(Getis Ord GI*)
Q5
How can we assess the spatial access of essential jobs for Atlanta residents by income using public transportation?
40000
Essential Job Clusters
Q3
RESEARCH QUESTIONS
2500
50000
Accessibility Score
STRAIGHT-LINE DISTANCE
60000
Accessibility Score
GA
Inverse Power, α=1.0
3000
Accessibility Score
RAIGHT-LINE DISTANCE
Atlanta
Aggregation
Public transit is important for marginalized groups in Atlanta as 75% of public transit riders are low-income, and 70% of riders are Black. Compounded with traffic congestion, rising housing prices, and the economic recession from the pandemic, understanding people’s access to jobs is important. Even with the pandemic, many low-income residents still have to commute to work as their jobs are considered essential and can only be done in person.
bs per CBG Population
BACKGROUND
Gravity Model
Travel Time = 60 min
Accessibility Score
EQUITY IN ACCESSIBILITY
Tamim Abedin Moses Levich Soyeon Kim Advanced Spatial Analysis Spring 2021 Columbia GSAPP.
Miles
0
2
4