New subject: [CTPP] mode to work by small workplace geographies

27 Dec 2010

Hi Everyone!  Hope you had a relaxing weekend! 

Tables for small geography at the WORKPLACE.  The ACS tables for
2005-2009 (5 - year summary) do NOT have small geography "for workplace
geography."  This kind of table will be available in the CTPP 5-year
(2006-2010) which we expect in 2012.  The reason is that the Census
Bureau's regular geocoding for workplaces only goes down to county and
place.  About 25% of responses do not have sufficient detail for block
level geocoding, therefore an imputation routine is required to report
workplace at tract or blockgroup geography.  We call this imputation
routine "extended workplace allocation" and the work is currently being
developed for the CTPP.  Once it is in place for the CTPP 2006-2010, we
hope that the Census Bureau will be able to apply it for the ACS
standard products. 

Historically, the CTPP was the only decennial census "long form" product
that included tabulation for workplace geography and for the flow
between home and work.  I was glad to see that the ACS Office started to
include workplace tabulations in the ACS standard table set.  

Elaine Murakami

FHWA Office of Planning, Wash DC

206-220-4460 (in Seattle)

As you probably know, the CTPP 2006-2010 will have additional small area
data that is synthetic or "modeled." This is NCHRP 08-79 project, in
progress by Westat.    This work is to avoid the heavy data suppression
we expected given the CB requirement to protect individual
confidentiality, and some of the small shares of specific commute modes
that increase the probability of matching to a unique record.  The job
is to develop models that retain the characteristics of the original
data, so that the resulting data is still usable for transportation
planning, but still protects individual confidentiality.  Because the
work is done at the Census Bureau, the perturbed data can be compared to
the original data.

From: ctpp-news-bounces(a)chrispy.net
[mailto:ctpp-news-bounces(a)chrispy.net] On Behalf Of Flintoft, Anna E.
Sent: Monday, December 27, 2010 6:49 AM
To: ctpp-news(a)chrispy.net
Subject: [CTPP] mode to work by small workplace geographies

Does anyone know when the census will release mode of transportation to
work by smaller workplace geographies than place?  I was disappointed
that the 2005-2009 ACS didn't have it.  Coming up with a work trip mode
split for downtown is something people ask us about all the time.

Thanks.

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Anna Flintoft, PTP

Transportation Planner

Department of Public Works - Transportation Planning and Engineering

City of Minneapolis

Room 301, City of Lakes Building
309 2nd Avenue South
Minneapolis, MN 55401

(612) 673-3885 (office)

(612) 269-9410 (cell)

anna.flintoft(a)ci.minneapolis.mn.us

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RE: [CTPP] mode to work by small workplace geographies