thanks jeff for the info. i am sure many on the list will find it
interesting. i especially liked the part about the confidentiality
thresholds--especially since there is no hard evidence of how one can
disclose an individual other than some assertions by census staff.
Subject: Re: [CTPP] Re: Geographic coverage, C2SS & ACS
Date: Tue, 20 Nov 2001 09:03:52 EST
From: StarkRPC(a)aol.com
To: edc(a)berwyned.com
Mr. Christopher,
I had the opportunity to attend one of the 12 regional census press
conferences concerning C2SS and ACS held Nov. 14th and 15th around the
county. Due to the embargoed nature of the data and some of the briefing
materials I waited until today to send this. If you feel this
information is
useful to the list-serve, please post it.
Officials did confirm that "small geographic areas" are indeed census
tracts.
It will probably take the full four year cycle (2004-2008) to produce
this
level of geography. I also asked whether or not BG' s or TAZ's would
be a possibility in the future. The response was that the Census Bureau
would
"most likely" continue to support the planning community with special
tabulations, with the added disclaimer "if confidentiality thresholds
are
met." Considering the size of the sample and also the size of many
TAZ's I
wonder what our chances are.
The press conference seemed to have the tone of a pitch for
Congressional
funding. If funded ($137 million/year) data for areas less than 20,000
won't
be available until 2008. It seems to me at least that it will be a
stretch
to get BG or TAZ level data for 2010. Many major newspapers have
stories on the release of C2SS today. Read a couple to get a feel for
what others think. My comments can be found in the local section of
www.cantonrep.com.
Jeff Dotson, Sr. Planner
Stark County Regional Planning Commission/
Area Transportation Study
(330) 451-7402
starkrpc(a)aol.com
www.starkrpc.org
I wholeheartedly agree with Ms. Brennan's assessment. I would also take it
one step further to say that the vast majority of the data from census
programs are not delivered in a timely enough fashion to be truly useful.
The most use I have gotten out of Census data is as a check on our own data
collection or projections. It would be much more useful to limit the number
of questions asked and to provide the responses in a timely fashion than to
ask all of the questions I have seen in the past.
Bill Austin, AICP
Greater Wilmington Urban Area MPO
"Laureen Brennan"
<lbrennanompo@hawa To: <ctpp-news(a)chrispy.net>
ii.rr.com> cc:
Sent by: Subject: RE: [CTPP] more on what the acs
owner-ctpp-news@ch may or may not give us
rispy.net
11/21/01 06:25 PM
Please respond to
lbrennanompo
Dear Mr. Christopher:
What is the purpose of the ACS, and C2SS? Is the purpose to collect data
for the sake of collecting data or seeing if the data can be collected, or
is the purpose to collect usable data? If it is to collect data for data's
sake, then $137m a year is a waste of money. If the purpose is to collect
usable data, it should be collected and distributed at a level that is
usable -- blocks, block groups, TAZs. Collecting estimates at the tract
level is a waste of time and money for most users. By the time you
manipulate the data and try to disaggregate it, you might as well take a
guess and forget about the ACS/C2SS.
If Congress wants the users to base their decisions on the data collected
by
the ACS and/or the census, then the ACS/Census should collect data that can
be used to make decisions. For instance, (just one example) how are you
going to determine Title VI and Environmental Justice neighborhoods using
Tract level information?
We need a Secretary of Home Data.
Laureen Brennan
-----Original Message-----
From: owner-ctpp-news(a)chrispy.net [mailto:owner-ctpp-news@chrispy.net]On
Behalf Of ed christopher
Sent: Tuesday, November 20, 2001 5:01 PM
To: ctpp-news maillist
Subject: [CTPP] more on what the acs may or may not give us
thanks jeff for the info. i am sure many on the list will find it
interesting. i especially liked the part about the confidentiality
thresholds--especially since there is no hard evidence of how one can
disclose an individual other than some assertions by census staff.
Subject: Re: [CTPP] Re: Geographic coverage, C2SS & ACS
Date: Tue, 20 Nov 2001 09:03:52 EST
From: StarkRPC(a)aol.com
To: edc(a)berwyned.com
Mr. Christopher,
I had the opportunity to attend one of the 12 regional census press
conferences concerning C2SS and ACS held Nov. 14th and 15th around the
county. Due to the embargoed nature of the data and some of the briefing
materials I waited until today to send this. If you feel this
information is
useful to the list-serve, please post it.
Officials did confirm that "small geographic areas" are indeed census
tracts.
It will probably take the full four year cycle (2004-2008) to produce
this
level of geography. I also asked whether or not BG' s or TAZ's would
be a possibility in the future. The response was that the Census Bureau
would
"most likely" continue to support the planning community with special
tabulations, with the added disclaimer "if confidentiality thresholds
are
met." Considering the size of the sample and also the size of many
TAZ's I
wonder what our chances are.
The press conference seemed to have the tone of a pitch for
Congressional
funding. If funded ($137 million/year) data for areas less than 20,000
won't
be available until 2008. It seems to me at least that it will be a
stretch
to get BG or TAZ level data for 2010. Many major newspapers have
stories on the release of C2SS today. Read a couple to get a feel for
what others think. My comments can be found in the local section of
www.cantonrep.com.
Jeff Dotson, Sr. Planner
Stark County Regional Planning Commission/
Area Transportation Study
(330) 451-7402
starkrpc(a)aol.com
www.starkrpc.org
For those going to the Transportation Research Board's Annual meetings
this January (http://www4.trb.org/trb/annual.nsf) the subcommittee on
Census Data for Transportation Planning is holding a special Sunday
workshop entitled "Census Data, Beyond 2000".
The workshop will take place on Sunday January 13, 2002 in the Lincoln
West room of the Hilton Hotel from 8:30 AM to 12:00 PM.
As you may know the Census Bureau is requesting funding to begin the
full implementation of the American Community Survey (ACS) in 2003.
Since the ACS is intended to take the place of the decennial census
long form, this workshop will serve as a forum to update the
transportation community on the status of the ACS program, the outlook
for implementation, and recent research efforts to begin the process of
replacing the long form data with continuous measurement in
transportation planning and research. At the same time, this workshop
is deigned to inform officials and policy makers of the needs and issues
as seen by the transportation community. Potential users of the ACS
will be provided an opportunity to voice concerns, raise questions, and
formulate a research agenda that will serve to ensure a smooth
transition from the long form to the ACS.
--
Ed Christopher
Metropolitan Activities
Midwest Resource Center
Federal Highway Administration
19900 Governors Drive
Olympia Fields, Illinois 60461
708-283-3534 (V)
708-283-3501 (F)
just send it to ctpp-news(a)chrispy.net
if you post from an address that is not the one you subscribed from it
might take a half day of so to hit the list. we have a somewhat manual
system for checking what gets caught by the spam blocker.
Scott Ferry wrote:
> Greetings: Could you please tell me how to post a question to the CTPP
> list? Many thanks. Scott FerryTransportation PlannerRegional
> Intergovernmental CouncilSouth Charleston, WV
Just like TAZs, census tracts were created at the request of data users.
They were first defined for the 1910 Census for the 8 largest cities. They
were requested by a clergyman in New York City so that they could do a
better job of providing social services to the poor. Here at the Denver
MPO, we have been the agency to coordinate the update of tract definitions
and boundaries since the 1970 Census. That gives us the opportunity to make
them as consistent with TAZs as the criteria allow.
Larry Mugler
DRCOG
-----Original Message-----
From: Mehta, Jamsheed [mailto:MEHTA_J@ci.wichita.ks.us]
Sent: Thursday, November 08, 2001 3:04 PM
To: 'ed christopher'; 'ctpp-news maillist'
Subject: RE: [CTPP] Re: Geographic coverage, C2SS & ACS
Its my understanding that "Tracts" are based on population criteria
(minimum, optimal, and maximum number of persons). TAZs may be too small in
some cases to fit the "tract" definition, or may not have any population at
all.
. . Jamsheed Mehta, AICP
Chief Planner, Transportation Division
Wichita-Sedgwick County
Metropolitan Area Planning Department
Tel: (316) 268-4457
Fax: (316) 268-4390
e-mail: mehta_j(a)ci.wichita.ks.us
-----Original Message-----
From: ed christopher [mailto:edc@berwyned.com]
Sent: Thursday, November 08, 2001 3:37 PM
To: 'ctpp-news maillist'
Subject: Re: [CTPP] Re: Geographic coverage, C2SS & ACS
since patty raised the issue of tracts, i have often wondered why do we have
tracts? why don't we
have a zonal system in urban areas that is created by the public data
users--something like TAZs. in
many areas the TAZs are developed by a collection agencies with planning and
data responsibilities.
if memory serves me tracts were historically a creation of the census bureau
which is a data
collector. TAZs are a product of regional planning organizations (which
happen to have
transportation responsibilities) which are data users.
Patty Becker wrote:
> Again, please feel free to post this to the list serve if you wish.
>
> My clear understanding is that "small area" means tract. I don't think
> anyone thinks the 60 month data will be good enough for block groups.
>
> If TAZs are tract equivalent, then the data should be as good as for
> tracts. For heavy attractor TAZs which are split below tract level, the
> transportation community has to negotiate with the bureau for a special
tab
> to deliver all TAZs. The data should support the tab
> adequately, Meanwhile, of course, someone is going to have to be
> responsible (MPO by MPO and state by state) for keeping the geocoding file
> up to date!
>
> No one knows whether these 60 month data are going to "feel right." Only
> time will tell. But in any event the CTPP users will have data equivalent
> to that for all users who use tracts. Meanwhile, we still have all these
> hurdles in Congress, etc. etc.
>
> Patty Becker
---
Ed Christopher
Metropolitan Specialist
Midwest Resource Center
Federal Highway Administration
19900 Governors Drive
Olympia Fields, Illinois 60461
708-283-3534 (V)
708-283-3501 (F)
----- Original Message -----
From: "Ed Herlihy (@home.com)" <ed.herlihy(a)home.com>
To: "ed christopher" <edc(a)berwyned.com>
Sent: Thursday, November 08, 2001 7:06 PM
Subject: Re: [CTPP] Re: Geographic coverage, C2SS & ACS
> I would be happy with tract level data if the JTW info provides some
better
> data on total retail versus non ratail jobs at the destination end of the
> work trip. Localities have pretty good data on square footage by type but
> have lots of trouble keeping up with small area job estimates. The jobs
per
> square foot estimates seem like a moving target these days
>
> I know the data is there, but I am not sure the CTPP or this new ACS tabs
> will do a retail vs non-retail tabulation.
>
> I hope so, because of lot of forecasting models use jobs for work trip
> attration estimates.
>
> Ed Herlihy
> Transportation Consultant
> Alexandria VA
> 703-914-4850
>
> ----- Original Message -----
> From: "ed christopher" <edc(a)berwyned.com>
> To: "'ctpp-news maillist'" <ctpp-news(a)chrispy.net>
> Sent: Thursday, November 08, 2001 4:36 PM
> Subject: Re: [CTPP] Re: Geographic coverage, C2SS & ACS
>
>
> > since patty raised the issue of tracts, i have often wondered why do we
> have tracts? why don't we
> > have a zonal system in urban areas that is created by the public data
> users--something like TAZs. in
> > many areas the TAZs are developed by a collection agencies with planning
> and data responsibilities.
> > if memory serves me tracts were historically a creation of the census
> bureau which is a data
> > collector. TAZs are a product of regional planning organizations (which
> happen to have
> > transportation responsibilities) which are data users.
> >
> > Patty Becker wrote:
> >
> > > Again, please feel free to post this to the list serve if you wish.
> > >
> > > My clear understanding is that "small area" means tract. I don't
think
> > > anyone thinks the 60 month data will be good enough for block groups.
> > >
> > > If TAZs are tract equivalent, then the data should be as good as for
> > > tracts. For heavy attractor TAZs which are split below tract level,
the
> > > transportation community has to negotiate with the bureau for a
special
> tab
> > > to deliver all TAZs. The data should support the tab
> > > adequately, Meanwhile, of course, someone is going to have to be
> > > responsible (MPO by MPO and state by state) for keeping the geocoding
> file
> > > up to date!
> > >
> > > No one knows whether these 60 month data are going to "feel right."
> Only
> > > time will tell. But in any event the CTPP users will have data
> equivalent
> > > to that for all users who use tracts. Meanwhile, we still have all
> these
> > > hurdles in Congress, etc. etc.
> > >
> > > Patty Becker
> >
> > ---
> > Ed Christopher
> > Metropolitan Specialist
> > Midwest Resource Center
> > Federal Highway Administration
> > 19900 Governors Drive
> > Olympia Fields, Illinois 60461
> > 708-283-3534 (V)
> > 708-283-3501 (F)
> >
> >
>
Why do we have tracts?
Yes, ed, your memory is correct about the Bureau "creating" census tracts,
but they relied on the recommendations of the local "Census Tract
Committees" of data users to provide the boundaries. This is still the
process for the decennial review of the tracts. (I worked on coordinating
this review in the Cincinnati CMSA for 1990 and 2000.)
But, we have census tracts mainly as geographically stable over time
statistical analytical areas. Municipalities, enumeration districts and
zip-codes, on the other hand, keep moving their boundaries. This is also the
reason that we can split census tracts in growing areas, but that they need
to nest to the same parent tract of the preceding census, and that the ID
tract numbers are changed with suffixes so that it is obvious that the areas
represented by the tract-split numbers aren't the same.
My experience with TAZ's, again with the Cincinnati MPO, is that you
wouldn't want to go there. We have just overhauled our tazs for 2000. Most
changes are splits, but some aren't. They don't match tracts. And many are
small enough to represent blocks in the CBD and major traffic generators
(shopping centers, employers) with little or no resident population to
disclose.
Census tracts are good.
Don Burrell, Senior Planner
Bicycle / Pedestrian Coordinator (formerly data person)
OKI Regional Council of Governments
801-B West Eighth St. Suite 400
Cincinnati, OH 45203-1607
513-621-6300
513-621-9325 - fax
dburrell(a)oki.org <mailto:dburrell@oki.org>
<A bicycle is an instrument for playing the road>
-----Original Message-----
From: ed christopher [mailto:edc@berwyned.com]
Sent: Thursday, November 08, 2001 4:37 PM
To: 'ctpp-news maillist'
Subject: Re: [CTPP] Re: Geographic coverage, C2SS & ACS
since patty raised the issue of tracts, i have often wondered why do we have
tracts? why don't we
have a zonal system in urban areas that is created by the public data
users--something like TAZs. in
many areas the TAZs are developed by a collection agencies with planning and
data responsibilities.
if memory serves me tracts were historically a creation of the census bureau
which is a data
collector. TAZs are a product of regional planning organizations (which
happen to have
transportation responsibilities) which are data users.
Patty Becker wrote:
> Again, please feel free to post this to the list serve if you wish.
>
> My clear understanding is that "small area" means tract. I don't think
> anyone thinks the 60 month data will be good enough for block groups.
>
> If TAZs are tract equivalent, then the data should be as good as for
> tracts. For heavy attractor TAZs which are split below tract level, the
> transportation community has to negotiate with the bureau for a special
tab
> to deliver all TAZs. The data should support the tab
> adequately, Meanwhile, of course, someone is going to have to be
> responsible (MPO by MPO and state by state) for keeping the geocoding file
> up to date!
>
> No one knows whether these 60 month data are going to "feel right." Only
> time will tell. But in any event the CTPP users will have data equivalent
> to that for all users who use tracts. Meanwhile, we still have all these
> hurdles in Congress, etc. etc.
>
> Patty Becker
---
Ed Christopher
Metropolitan Specialist
Midwest Resource Center
Federal Highway Administration
19900 Governors Drive
Olympia Fields, Illinois 60461
708-283-3534 (V)
708-283-3501 (F)
Its my understanding that "Tracts" are based on population criteria
(minimum, optimal, and maximum number of persons). TAZs may be too small in
some cases to fit the "tract" definition, or may not have any population at
all.
. . Jamsheed Mehta, AICP
Chief Planner, Transportation Division
Wichita-Sedgwick County
Metropolitan Area Planning Department
Tel: (316) 268-4457
Fax: (316) 268-4390
e-mail: mehta_j(a)ci.wichita.ks.us
-----Original Message-----
From: ed christopher [mailto:edc@berwyned.com]
Sent: Thursday, November 08, 2001 3:37 PM
To: 'ctpp-news maillist'
Subject: Re: [CTPP] Re: Geographic coverage, C2SS & ACS
since patty raised the issue of tracts, i have often wondered why do we have
tracts? why don't we
have a zonal system in urban areas that is created by the public data
users--something like TAZs. in
many areas the TAZs are developed by a collection agencies with planning and
data responsibilities.
if memory serves me tracts were historically a creation of the census bureau
which is a data
collector. TAZs are a product of regional planning organizations (which
happen to have
transportation responsibilities) which are data users.
Patty Becker wrote:
> Again, please feel free to post this to the list serve if you wish.
>
> My clear understanding is that "small area" means tract. I don't think
> anyone thinks the 60 month data will be good enough for block groups.
>
> If TAZs are tract equivalent, then the data should be as good as for
> tracts. For heavy attractor TAZs which are split below tract level, the
> transportation community has to negotiate with the bureau for a special
tab
> to deliver all TAZs. The data should support the tab
> adequately, Meanwhile, of course, someone is going to have to be
> responsible (MPO by MPO and state by state) for keeping the geocoding file
> up to date!
>
> No one knows whether these 60 month data are going to "feel right." Only
> time will tell. But in any event the CTPP users will have data equivalent
> to that for all users who use tracts. Meanwhile, we still have all these
> hurdles in Congress, etc. etc.
>
> Patty Becker
---
Ed Christopher
Metropolitan Specialist
Midwest Resource Center
Federal Highway Administration
19900 Governors Drive
Olympia Fields, Illinois 60461
708-283-3534 (V)
708-283-3501 (F)
Elizabeth Hartmann wrote:
> Hello,
> I work in transportation planning, and we are currently evaluating data availability regarding the C2SS and the American Community Survey. I understand that the ACS will provide yearly info on population groups of 65,000 or more, and that for smaller areas, several years' data can be pooled to maximize reliability.
>
> Within this frame, at how fine a geographic level will this data be available? Currently, the decennial census provides data down to the block group level; will the C2SS and the ACS provide transportation data at this fine a level?
>
> Thank you!
> Liz Hartmann, Ph.D.
> Research Analysis Specialist
> MNDOT:Office of Investment Management
just to confirm what we spoke about on the phone. i cannot say with any certainty what the final geography will be with ACS nor even its content. as i noted, two efforts are underway within OBM. 1) to advise congress on the content and 2) on methodology (which impacts on geographic levels). how congress will respond
is anyone's' guess. the mood in congress up to now has been to cut content and in january i am told the census issues will be moved over to another subcommittee that will have a chairman that is even more concerned about the questionnaire being "too" long.
as far as getting ACS at a large scale geography (like the 65K areas) that should not be an issue. over the years we have been told that multiple years of ACS data can be pooled to produce small area summaries, but how small the areas will be and if this comes to pass, is not a done deal. most of the detail
surrounding the ACS is still up in the air.
in terms of the content, several of us within DOT have made our case to OMB on the importance and legal needs for the transportation related questions. i believe that right now OMB is review the information submitted by all the federal agencies and will reporting out on it sometime in the future--this is an issue we
are following.
i cross posted this to our ctpp-listserve for others who may have similar questions or who might be able to expound on any of the points raised.
--
Ed Christopher
Metropolitan Specialist
Midwest Resource Center
Federal Highway Administration
19900 Governors Drive
Olympia Fields, Illinois 60461
708-283-3534 (V)
708-283-3501 (F)
Again, please feel free to post this to the list serve if you wish.
My clear understanding is that "small area" means tract. I don't think
anyone thinks the 60 month data will be good enough for block groups.
If TAZs are tract equivalent, then the data should be as good as for
tracts. For heavy attractor TAZs which are split below tract level, the
transportation community has to negotiate with the bureau for a special tab
to deliver all TAZs. The data should support the tab
adequately, Meanwhile, of course, someone is going to have to be
responsible (MPO by MPO and state by state) for keeping the geocoding file
up to date!
No one knows whether these 60 month data are going to "feel right." Only
time will tell. But in any event the CTPP users will have data equivalent
to that for all users who use tracts. Meanwhile, we still have all these
hurdles in Congress, etc. etc.
The C2Ss is separate from the ACS. There is no way that the number of
cases will allow for TAZ level reporting, even if the 2000 and 2001 surveys
are combined. Perhaps we can get combined data at the 100K level out of
them next year. I would suggest, however, that the CTPP community keep a
good handle on how the coding is proceeding for the C2SS--are they doing a
good job of it? The ACS will be like the C2SS in this regard and if there
are problems, it's important to be aware of them.
Patty Becker
At 02:05 PM 11/08/2001 -0600, ed christopher wrote:
>Elizabeth and Ed-- (note, I am not posting this to the listserv, but Ed can
>choose to post it if he wishes)
>
>At the current time, I believe that with the current plans for sampling for
>the ACS, it would take 5 years of accumulated data (60 months) for the
>Census Bureau to release small area data. However, if the sampling rate
>decreases to any large extent, it is not clear what would happen to small
>area data. To clarify Ed's earlier remarks, we do not know if "small area"
>means census tract, or block group level geography. We are very concerned
>about whether and how the transportation community will be able to generate
>an "equivalent" to a CTPP file from the ACS, and if reporting by TAZ will be
>possible or allowed.
>
>Elaine Murakami
>Federal Highway Administration
>
>Keith Miller wrote:
>
> > According to the Census Bureau
> > (http://www.census.gov/Press-Release/www/2001/ntc102901.html):
> >
> > "By 2004, the American Community Survey ... will produce estimates for
> > geographic areas and population groups of 65,000 or more, and by 2008, for
> > even the smallest areas and population groups in the country."
> >
> > Just what "the smallest areas and populations groups" means is anyone's
> > guess, but it was my understanding that they're targeting the block-group
> > level. But as Ed pointed out, this all depends on congress and funding...
> >
> > Also to address one point that Elizabeth asked in her original question,
> > "will the C2SS and the ACS provide transportation data at this fine a level
> > [block group]?" It is my understanding that the C2SS (Census 2000
> > Supplementary Survey) data will not be available for anything smaller than
> > counties or cities with more than 250,000 residents. The sample size of the
> > C2SS was not sufficient to support anything smaller than this. For the ACS,
> > see above.
> >
> > ------------------------------------------------------------------------
> > Keith Miller
> > Principal Planner: GIS and Modeling
> > North Jersey Transportation Planning Authority, Inc.
> > One Newark Center, 17th floor
> > Newark, NJ 07102
> > 973-639-8444
> > kmiller(a)njtpa.org
> >
> > -----Original Message-----
> > From: owner-ctpp-news(a)chrispy.net [mailto:owner-ctpp-news@chrispy.net]On
> > Behalf Of ed christopher
> > Sent: Wednesday, November 07, 2001 4:43 PM
> > To: Elizabeth Hartmann
> > Cc: elaine (fta) murakami; ctpp-news maillist
> > Subject: [CTPP] Re: Geographic coverage, C2SS & ACS
-------------------------------------------------------------------------------------------------
Patricia C. (Patty) Becker 248/354-6520
APB Associates/SEMCC FAX 248/354-6645
28300 Franklin Road Home 248/355-2428
Southfield, MI 48034 pbecker(a)umich.edu