Jim, 

While the CTPP program encouraged folks to better align their block groups with their TAZs, doing so, was not universal, and methods to do so varied. For instance, DVRPC tried to make new block groups more similar to TAZs (not always successfully) and others said they would just match their TAZS. 

Probably what others are indicating makes sense, although I think going off of strictly intersections of area is less desirable than perhaps weighing by the population of component blocks when looking at demographic information or employment of certain blocks if you have some proprietary, point-level employment source or maybe lehd (although they add a lot of noise for their geolocation at the block level. Still, if you have block groups with high concentrations of employment on one side and population on the other, using strictly area will give you a muddier result. 

Ben


On Fri, Jun 3, 2022 at 6:27 PM Edward Sullivan <egads@epsys.com> wrote:

 

 

From: Jim Hubbell [mailto:jimhubbell1975@gmail.com]
Sent: Friday, June 03, 2022 14:35
To: ctpp@listserv.transportation.org
Subject: [CTPP News] Roll up TAZs to Census Block Groups?

 

Hello CTPP Community,

 

Even though TAZs were officially retired by the Census Bureau, a lot of folks in the transportation continue to use the geographies (especially those from 2010). Today a colleague at StreetLight asked if it's possible to roll up TAZs into Census Block Groups. I couldn't recall off the top of my head whether this is possible, and if so, how to do it. It seems to me that TAZ delineation criteria required they nest into Census Tracts, but maybe also into Block Groups?

 

Any thoughts or guidance on this question would be greatly appreciated. Thanks!

 

Jim Hubbell

StreetLight Data

 

 

_______________________________________________
CTPP mailing list -- ctpp@listserv.transportation.org
To unsubscribe send an email to ctpp-leave@listserv.transportation.org
--

Working from Home  | 301.655.3170
Ben Gruswitz, AICP | Manager, Socioeconomic & Land Use Analytics 
(Pronouns: he/him)