MEMORANDUM
Date: June 18, 2009
To: Ed Christopher and ctpp-news(a)chrispy.net
From: Thabet Zakaria
Subject: Removal of Name From
ctpp.net
Dear Ed:
Please remove my name from
cttp.net effective June 30, 2009 because of retirement. I
would like to take this opportunity to thank you for reviewing my TRB papers and emails on
transportation surveys, census data, journey-to-work, population and employment estimates,
CTPP, and ACS during the last 30 years. Also, many thanks go to the members of this net
including, but not limited to, Elaine Murakami, Chuck Purvis, Nancy McGuckin, Ken
Cervenka, Catharine Lawson, Alan Pisarski, David Pearson, Rolf Schmitt, Peter Stopher,
Nanda Srinivasan, Jerry Everet, Kevin Tierney, Clara Reschovsky, and Jonette Kreideweis.
By the way, I have evaluated the latest results of the ACS (2007 and 2005-2007) and found
out that the ACS data are useless for all areas promised by the Census Bureau (65,000 and
20,000 population). Even at the county level (larger than 250,000 population), I had to
make some adjustments to the ACS data to make them reasonable. These adjustments are
based on local data and other census information. As you know, DVRPC does not use or
publish any unreasonable data. There are nine counties and 352 municipalities in the
region that depend on DVRPC data.
As you will recall, I have stated on this net and in many national conferences that the
current ACS methods and procedures will not produce accurate or usable zonal data for
transportation planning and travel forecasting. I hope that FHWA and AASHTO will convince
the Census Bureau to replace the ACS with the Long-Form in Census 2020. I think that
accurate data from the Long-Form every 10 years are much more useful to the transportation
community than erroneous data from the ACS every year.
Thabet Zakaria
Deputy Director, Technical Services
Delaware Valley Regional Planning Commission
Phone: (215) 238-2885
Email: tzakaria(a)dvrpc.org
Fax: (215) 592-9125