Thanks Liang for sharing the slides, much appreciated,very interesting presentation on a proposed metholodology for using larger area ACS estimates (themselves with a fairly large margin of error, as we know) to synthesize to PUMAs, which are themselves large area geography. However no margins of error are addressed that I can see in the presentation, though the last slide has as "next steps" an item that proposes inquiry into census block groups and census tracts. One potential issue is where do the controls for the small-area data come from if we are somehow coming up with the controls themselves, and then synthesizing cross-tabs from those controls. Among other things, margins of errors are something to keep in mind for NCHRP 08-79. Thanks, Guy Guy Rousseau Modeling Manager Atlanta Regional Commission From: ctpp-news-bounces(a)chrispy.net [mailto:ctpp-news-bounces@chrispy.net] On Behalf Of Liang Long Sent: Thursday, February 25, 2010 10:50 AM To: ctpp-news(a)chrispy.net Subject: [CTPP] Sakshaug's slides on CS FTP server As many of you are requiring Joe's research materials, I asked Joe's approval for sharing his presentation slides. Here it is: ftp://ftp.camsys.com/temp/outgoing/CTPP/JoeSakshaug_Synthetic.pdf <ftp://ftp.camsys.com/temp/outgoing/CTPP/JoeSakshaug_Synthetic.pdf> Liang Long Cambridge Systematics, Inc. 4800 Hampden Lane Suite 800 Bethesda, MD 20814 tel 301 347 9141 fax 301 347 0101 FHWA 202-366-6971 e-mail llong(a)camsys.com www.camsys.com