using lehd data for travel demand models : the florida experience
DESCRIPTION
Using LEHD Data for Travel Demand Models : The Florida Experience. presented by Krishnan Viswanathan Cambridge Systematics, Inc. Co-authors Vidya Mysore, Florida Department of Transportation Nanda Srinivasan, Cambridge Systematics, Inc. May 7, 2007. Outline. Motivation - PowerPoint PPT PresentationTRANSCRIPT
presented by
Krishnan Viswanathan Cambridge Systematics, Inc.
Co-authors
Vidya Mysore, Florida Department of TransportationNanda Srinivasan, Cambridge Systematics, Inc.
May 7, 2007
Using LEHD Data for Travel Demand Models : The Florida Experience
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Outline
Motivation
Longitudinal Employer Household Dynamics (LEHD) Description
Some Comparisons
FSUTMS Data Analysis
Summary
Future Directions
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Motivation
Review and possible use of LEHD and Employment data for travel demand modeling
Current and future directions of Census and other available data sources for transportation
Review of QCEW [Quarterly Census of Employment and Wages] (Employment data from AWI, state agency) and LEHD Data
Data integration
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LEHD Description
LEHD combines federal and state administrative data on employers and employees with core Census Bureau censuses and surveys
Local Employment Dynamics (LED) is a voluntary partnership between state labor market information agencies and the U.S. Census Bureau to develop new information about local labor market conditions
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LEHD Description
The data for LEHD will be based on Quarterly Census of Employment and Wages (QCEW/ES-202)
Number of people employed and the wages paid to the employees each quarter
Multi-establishment employers also provide individual worksite data
Preliminary annual data are available in June and final annual data are available in October of each year. Quarterly data are available six months after the end of each quarter
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LEHD Description Origin Destination Database
Work Profile – block group• # establishments • # workers• Worker distribution
• age• earnings• industry
• Demand/ Growth Indicators• Job creation/loss• Hires/separations• Earnings hires/separations
Home Block(U/I Wage Data)
Workplace Block(QCEW Data)
# of Workers (primary job) and # of Jobs
Home Profile – block group• # workers• Worker distribution
• age• earnings• industry
Acknowledgments : US Census Bureau
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LEHD Description Origin Destination Database
Yearh_geocodefullw_geocodefulljobs_alljobs_primjobs_priv_alljobs_priv_prim
Year YYYYFIPS state, FIPS county; Census tract, Census block; homeFIPS state, FIPS county; Census tract, Census block; workNumber of jobs to which workers made this tripNumber of primary jobs to which workers made this tripNumber of private sector jobs to which workers made this tripNumber of private sector primary jobs to which workers made this trip
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LEHD Description OD with ACS: Possible Model for Integration
Home Block(U/I Wage Data)
Workplace Block(QCEW Data)
# of Workers (primary job) and # of Jobs
Home Profile – block group• # workers• Worker distribution
• age• earnings• industry
Work Profile – block group• # establishments • # workers• Worker distribution
• age• earnings• industry
• Demand/ Growth Indicators• Job creation/loss• Hires/separations• Earnings hires/separations
ACS Data• Trip Time• Mode• Distance
Acknowledgments : US Census Bureau
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Some Comparisons
An old well reviewed favorite – CTPP
New kid on the block – LEHD
North East Regional Planning Model (NERPM) region – Duval, St. Johns, Clay and Nassau Counties (Jacksonville is major city)
CBD
CTPP LEHD
CTPP 1.00
LEHD 0.68 1.00
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Some ComparisonsTravel Statistics
Region Travel CTPP JOBS_PRIMARY
Total : All resident workers in NERPM Region 519,280 500,702
Travel within NERPM region 509,105 385,951
Travel from NERPM region to CBD 49,460 46,366
Travel outside NERPM region 10,175 114,751
98 percent (CTPP) vs. 77 percent (LEHD) travel within region
• Similar results in an earlier BTS Study by Cesar Singh
Under a quarter of LEHD travel is outside the region
Travel shares to CBD is approximately the same
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Some Comparisons Residual Plot
Total Workers Residual Plot
-1000
-800
-600
-400
-200
0
200
400
600
800
0 200 400 600 800 1000 1200 1400 1600 1800
Total Workers (CTPP Table T301C1)
Res
idu
als
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Some Comparisons CBD Distance
CTPP LEHD – Primary Jobs
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Some Comparisons CBD Distance
Distance from CBD - CTPP vs LEHD
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
0 to 5miles
5 to 10miles
10 to 15miles
15 to 20miles
20 to 25miles
25 to 30miles
More than30 miles
Distance
CTPP
JOBS_PRIMARY
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FSUTMS Data Analysis
Models Used
QCEW Data Analysis
Comparison between InfoUSA and QCEW data
Results
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Models Used
2005 NERPM CF Model 2000 Polk TPO Model
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QCEW (ES202) Data Analysis
December 2004 data used for analysis
Data overlaid to TAZ
Geocoded the data for address matching
ZDATA2 data developed from QCEW Data
Model Total QCEW Employment
Lat/Long Information Available
Geocoded to Model TAZ
Address Matched to TAZ
NERPM 728,044 487,954 468,755 176,957
Polk 438,190 182,675 169,771 167,370
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Comparison between InfoUSA and QCEW Data
NERPM QCEW InfoUSA Model
MAN. INDUSTRIAL 113,003 89,318 54,903
OTHER INDUSTRIAL 34,699 42,644 137,255
COMMERCIAL 145,355 126,640 182,157
SERVICE 352,655 274,766 420,058
TOTAL 645,712 533,368 794,373
POLK QCEW InfoUSA Model (2000)
INDUSTRIAL 41,133 35,761 41,684
COMMERCIAL 179,468 58,486 59,775
SERVICE 116,540 99,418 105,611
TOTAL 337,141 193,665 207,070
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Results
Model HBW Trips LEHD Primary Jobs
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Results
Model HBW Trips CTPP JTW Trips
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Results
Model HBW Trips
LEHD Primary Jobs
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Results
Model HBW Trips
CTPP JTW Trips
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Summary
Under reporting of internal trips
Model results are reasonable
QCEW data good source for employment data
Issues regarding data suppression
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Future Directions
Potential data source for model calibration, more review of long distance trips to work
Coordination effort for data aggregation with AWI
Work with Census Bureau to produce LEHD for Florida model
Variability of data over time
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Acknowledgments
Jim Baxter, Modeling Manager, FDOT District 1
Milton Locklear, Modeling Manager, FDOT District 2
Kathie Hughes, David Thurmond, AWI
Pam Schenker, ex-AWI