New subject: [CTPP] ACS/CTPP vs LEHD

6 Jun 2012

Reading the documentation of the two data resources: always a good place to start.

At regional or state level of summary, totally different data frames is your main issue:

a.       Census ACS counts workers through a household survey, relying on
individually-provided info on work.  Many kinds of work are counted, including
self-employment and occasional casual work.

b.      Meanwhile, the LED uses the data frame of BLS QCEW, counting wage & salary
jobs that are "covered" by the Unemployment Insurance system.  In Minnesota,
over 20% of BEA-counted jobs (a broader employment concept) are outside of this frame, are
*not* covered, and thus not counted in LED.

At local level, there are still other issues:

a.        How well can Census ACS represent job locations?

b.      And does the LED program move its workplace locations around on the map, in order
to obscure exact location?

Hope that helps.  Good luck.

Todd Graham  |  Principal Forecaster
Metropolitan Council  | 390 North Robert Street  |  Saint Paul, MN  55101
tel: 1+651-602-1322  |  fax: 1+651-602-1674  |  e:
todd.graham(a)metc.state.mn.us<mailto:todd.graham(a)metc.state.mn.us>
in: www.linkedin.com/in/toddgraham<http://www.linkedin.com/in/toddgraham>
Visit www.metrocouncil.org/data<http://www.metrocouncil.org/data> for the latest in
regional information.

From: ctpp-news-bounces(a)chrispy.net [mailto:ctpp-news-bounces(a)chrispy.net] On Behalf
Of Lindeman, Nicholas (MPO)
Sent: Wednesday, June 06, 2012 3:22 PM
To: 'ctpp-news(a)ryoko.chrispy.net'
Subject: [CTPP] ACS/CTPP vs LEHD

I've sent the following query to both the ACS and CTPP but have not (yet) received a
response. I was hoping someone on the mailing list might be able to provide assistance.

I've been working with Longitudinal Employer-Household Dynamics (LEHD)in On the Map.
Specifically worker inflow/outflow analysis at the county level. I've discovered that
there is a significant difference between the LEHD data and ACS Place of Work data from
the 2008-10 3-Year ACS product. I've found that for the Middle Tennessee (Nashville)
region the % of workers residing outside their home county is nearly 17 percentage points
higher in the LEHD data than in the ACS data. Please see the attached table.

I've been tasked with determining the reason(s) for this difference. Any assistance
you can provide would be greatly appreciated

Thank you,
Nick Lindeman

Nicholas Lindeman
Economic & Systems Data Analyst
Nashville Area MPO
800 2nd Ave. S.
P.O. Box 196300
Nashville, TN 37219-6300
(615) 862-7198
lindeman(a)nashvillempo.org<mailto:lindeman(a)nashvillempo.org>
http://www.nashvillempo.org<http://www.nashvillempo.org/>

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Re: [CTPP] ACS/CTPP vs LEHD