Turns out internal (intra-tract) flows are not reported. This should account for nearly all the missing workers.

From: ctpp-news-bounces@chrispy.net [mailto:ctpp-news-bounces@chrispy.net] On Behalf Of Marchwinski, Thomas
Sent: Thursday, May 26, 2016 10:26 AM
To: ctpp-news@chrispy.net
Subject: Re: [CTPP] CTPP animation map (Not CTPP, actually)

They may only be mapping those flows that have enough records so there is not an imputed or suppressed O-D pair, which would mean sometimes up to 50% of the records do not have flows, so its missing half of the flows. Those show up as 0 workers due to suppression. Tom Marchwinski

From: ctpp-news-bounces@chrispy.net [mailto:ctpp-news-bounces@chrispy.net] On Behalf Of Weinberger Penelope
Sent: Thursday, May 26, 2016 10:12 AM
To: ctpp-news@chrispy.net
Subject: Re: [CTPP] CTPP animation map (Not CTPP, actually)

I would be cautious, just did a quick check, it says ACS, but unsourced as to what ACS (I��m guessing 2009 �� 2013 county to county flows �� otherwise OD pairs are very tricky), also looking at just Montgomery county and DC, and expanding the tool to its maximum range (zero to 293 miles) it��s missing about half the total workers in each of those. Also, tracts are referenced, but that set is not reported at tract. I welcome your thoughts.

Penelope Z. Weinberger

CTPP Program Manager

AASHTO

202-624-3556

ctpp.transportation.org

From: ctpp-news-bounces@chrispy.net [mailto:ctpp-news-bounces@chrispy.net] On Behalf Of Nancy Reger
Sent: Wednesday, May 25, 2016 4:08 PM
To: ctpp-news@chrispy.net
Subject: [CTPP] CTPP animation map

Check out this CTPP animation map �� we didn��t make it. It��s very cool, wish we had-

http://bigbytes.mobyus.com/commute.aspx

Nancy Reger, AICP

Director, Data & Mapping | Mid-Ohio Regional Planning Commission
T: 614.233.4154 | M: 614.228.2663 | nreger@morpc.org

111 Liberty Street, Suite 100 | Columbus, OH 43215