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