Re: [CTPP] ACS/CTPP vs LEHD

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@metc.state.mn.us<mailto:todd.graham@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@chrispy.net] On Behalf Of Lindeman, Nicholas (MPO) Sent: Wednesday, June 06, 2012 3:22 PM To: &#39;ctpp-news(a)ryoko.chrispy.net&#39; 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@nashvillempo.org<mailto:lindeman@nashvillempo.org> http://www.nashvillempo.org<http://www.nashvillempo.org/> ________________________________ This email is intended to be read only by the intended recipient. This email may be legally privileged or protected from disclosure by law. If you are not the intended recipient, any dissemination of this email or any attachments is strictly prohibited, and you should refrain from reading this email or examining any attachments. If you received this email in error, please notify the sender immediately and delete this email and any attachments.