Upload
others
View
3
Download
0
Embed Size (px)
Citation preview
Examining Changes in Commuting Metrics Across Two Decades with LEHD
Data.
Daniel Schleith, Department of Geography, University of Cincinnati, 401 Braunstein Hall, Cincinnati, OH 45221-0131, E-mail: [email protected]
Michael J. Widener, PhD, Department of Geography, University of Cincinnati, 401 Braunstein
Hall, Cincinnati, OH 45221-0131, E-mail: [email protected]
1
Introduction • Some amount of travel to work is “required” by the layout
of a region. • Actual travel to work always higher than this required
amount.
• z
2
Background
3
Horner, M. W. (2002) Extensions to the concept of excess commuting. Environment and Planning A, 34, 543-566.
Commuting Measures • Observed Commutes (Tobs) The average commute distance
• Theoretical Minimum Commute (Tmin) Measure of jobs-housing balance
• Theoretical Maximum Commute (Tmax) Measure of overall dispersion or sprawl
• Excess Commuting (EC) (Tobs – Tmin) / Tobs
• Commuting Range (R) Tmax – Tmin
• Capacity Used (CU) (Tobs – Tmin) / R
4
Metro Locations
5
Considerations for the analysis
• 25 metro regions • 2 years (2002 & 2011) • 2 geographic extents (the 1990 metro
definition and the 2010 metro definition) • Road network distance used as the
commuting cost. • Scaling the underlying geography to be
computationally feasible.
6
LEHD Data
• Published by the census bureau with almost complete national coverage Massachusetts missing, some states missing 2002, 2003
• Created from state unemployment insurance records • Consists of per block counts of residents and workers • Available from 2002-2011 currently • Already aggregated to 2010 blocks for 02-09 • Some workers are not included in the data Migrant workers, uniformed military, and self-employed
7
8
9
10
11
Rank Order Comparison Tmin
12
13
14
15
16
17
18
Discussion • We recalculated all of the commuting
measures from Horner’s 2002 paper for 25 metro regions.
• Understand how the urban forms are changing over time. Miami’s results support a polycentric urban form
being able to facilitate shorter commutes Overall metros remain fairly consistent
o Especially with 1990 boundaries preserved oColumbus the only metro to decrease in Tmin, Tobs,
and Tmax from 2002 to 2011.
19
Appendix
The Transportation Problem
20