Tim,
We have used InfoUSA the last few years. It looks very similar to the InfoGroup product.
You've mentioned the problems we also have run into with InfoUSA.
There is double counting in the public sector (an employee counted under a department also
counted under the agency total). There were a few branch vs. headquarter issues, but it
was actually in pretty good shape.
We culled through the largest employers looking for suspicious employee totals and
duplicate employers. The result was the total employment being reduced by 4.5%, but we
still think it is about 10% too high.
I am unsure on the source InfoUSA used for geocoding addresses (never did get a clear
answer from InfoUSA on that) but it was significantly different than our GIS base mapping
in a few areas. So, some manual clean up was needed to move employers to the correct side
of a street.
Also, about 3% of the employers were geocoded to a ZIP code centroid (these included PO
boxes and other addresses InfoUSA was unable to geocode). We were able to geocode about
half of these.
I'm also interested in hearing from others experiences with these proprietary data
sets. Thanks.
Dan Seidensticker
From: ctpp-news-bounces(a)chrispy.net [mailto:ctpp-news-bounces@chrispy.net] On Behalf Of
Reardon , Tim
Sent: Tuesday, June 28, 2011 2:15 PM
To: 'ctpp-news(a)chrispy.net'
Subject: [CTPP] Proprietary Employer Data -- Comments on the various providers?
I have managed to assemble some funding to acquire employer data for our 164-municipality
transportation modeling region in Eastern MA, and I am wondering if any of you have
comments on the accuracy and utility of the various proprietary employer data sources
currently available. I have been in conversations with two major providers (InfoGroup and
Dun & Bradstreet) and have received sample files for certain zip codes, but it is hard
to assess the accuracy or completeness of either sample.
I'm wondering if anybody can offer insight on working with such data, and whether you
have suggestions on choosing a vendor. We will be using it primarily to determine
employment by sector at very fine geographies (250m or 1km grid cells) for land use
planning and analysis. Some concerns we have already identified include: branch vs.
headquarters employment, public sector employment, "paper companies" and
verification, and the accuracy of the goecoded location that accompanies each record.
Any thoughts are appreciated. Feel free to reply off-list if concerned about publicly
trumpeting or bashing somebody's product.
Thanks,
Tim Reardon
___________________________________________
Timothy G. Reardon -- Senior Regional Planner
Metropolitan Area Planning Council
60 Temple Place | Boston, MA 02111
617-451-2770 x2011
treardon@mapc.org<mailto:treardon@mapc.org>
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Say it with a map! Find data and bring it alive at
www.MetroBostonDataCommon.org!
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