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by Chris Parrinello

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26 years

Table Content -Reply

by Nathan Erlbaum

if you have ever looked at the table headings they are sometimes very difficult to figure out what they actually contain. For instance, if you want the JTW number of workers by mode there really isn't a table heading for this. JTW is part C and table C1 is time to work. Its heading is "Time leaving home to go to work-total and peak period by means of transportation to work"...universe workers 16+ who did not work at home. Each cell contains the number of workers, not the time they spent going to work by that mode; the table coordinates tell you that the table contains 2 tables sequentially first coordinates 1,1 to 1,19 contain the total and then the peak period with table coordinates 2,1 to 2,19. Table headings should be immediately intuitive!!!!! What needs to be done is that the table headings for C1 must say what the table contains:" workers, leaving home to work by mode of travel; daily and peak period" universe of workers 16+ who did not work at home. This way you immediately know the contents are workers all day and peak period Get an English teacher to write or review the headings, the products produced by Census are written in Census Jargon which at best is unclear because it tries to be overly precise and interpretation can be very tough even knowing what you are reading. >>> ed c <berwyned(a)mcs.com> 12/10/98 06:20pm >>> below is a dialogue that has been going on that i believe would be of interest to the entire ctpp mail list. it is extremely topical because just today Elaine Murakami called to remind me that i need to get something written up regarding our survey of several trb committees regarding the content (tables) of the ctpp package. here is a web page that presents some preliminary work in that area. don did remind me of an early product that even we in chicago used (stf s-5). http://www.mcs.com/~berwyned/census/notes/content.html needless to say any comments folks have on content for the ctpp (the tables) would be appreciated. i also recommend that you post your comments to the list ed christopher ------------------------------------------------ Don, Let me see what I can answer right now and what has to go into the hopper: > Place of work outside SMSA of residence. This needs a further > breakdown. Our Cincinnati area is a 13 co. CMSA so the data for > "outside each pmsa" doesn't tell me if the worker is in the other > pmsa. Similarly, we are adjacent to the Dayton msa and I can't > tell if the workers are coming to or from there. The county and > major city breakouts in this table are also valuable. (CBD?) > These concerns apply mainly to the standard tabulations. I > strongly recommend that the STF-S-5 commuter tabulations > be prepared again for nation-wide county to county work > trip commuting. I actually depend on > these for my regional in and out commuting and, consequently, > the regional net employment. I think the work flows have to come from the county to county file, and I would assume that will be repeated. It will make sure it's on our list. Actually, I was never aware of it as a formally named product (STF5?) but I did have a copy of it for Michigan counties. The issue of grouping counties as areas on the CTPP has to be fought out within the transportation planning community. > Another issue is continuation of the non-motorized travel modes > of biking and walking along with working at home. (Assuming > that transit and carpool modes will be continued.) These are > becoming more important in our region as we deal with air > quality conformity, congestion reduction and sprawl. Bicycle, Walked, and Worked at home are on the census dress rehearsal questionnaire, which means that unless something very unusual and unlikely happens, they will be on the 2000 long form. Once the data are collected, it's really up to the transportation planning community to decide how they will be tabulated on the CTPP. Also, you are going to have more opportunity to do your own tabulations via the Internet, so if you need something special you will probably be able to do it (albeit for a fee), or pay someone to do it for you. > Finally, an issue that I am assuming will be fixed with the > 2000 CTPP is place of work coverage in the suburban > and rural areas of our metro area. In 1990, less than half > of a county's workers were 'assigned' to a TAZ of work > in three of the 8 counties in our MSA. With nationwide TIGER coverage, I believe that all workplaces with street addresses are to be coded to tract/block. This of course permits their assignment to TAZ. The question is what happens with the inadequate workplace address entries on the census. You might want to talk to Phil Salopek about their plans on this. In 1980 Phil Fulton devised an elaborate allocation algorithm which fixed a lot of the problems in these data for workplaces inside the urbanized area, and with the full TIGER coverage the algorithm can be run for everywhere. However, if you have some major workplaces in the more rural counties that don't have addresses and that you want to be sure are coded correctly, you may be able to provide some workplace name information to the Bureau to assist with this. > And that brings to mind another final issue. In 1990, our CMSA > and MPO included the same 8 counties. In 1993, five more > counties were added to the CMSA, but not to our MPO > planning area. Therefore, our 2000 CTPP > will not include the added CMSA counties. Does this matter? The CMSA and the MPO don't have anything to do with each other, really. The CMSA is defined under OMB rules (now under review for possible significant changes; a federal register notice is due very soon); there can be a considerable amount of politics in the MSA/PMSA/CMSA designations because a lot of people think "the bigger the better" which makes for larger CMSAs. If you're not planning for the additional 5 counties, you probably don't need the CTPP for them. Besides, won't some other MPO have it (if the 5 counties are their own PMSA, they probably have some MPO coverage somewhere). > Thanks for asking! Hope this helps! > (copied to Ed Christopher) Ed, if you want to post this to the list, please feel free. ============================= Patricia C. (Patty) Becker 313/535-2077 APB Associates/SEMCC FAX 313/535-3556 17321 Telegraph #204 Home 248/355-2428 Detroit, MI 48219 pbecker(a)umich.edu

26 years

Table Content

by ed c

below is a dialogue that has been going on that i believe would be of interest to the entire ctpp mail list. it is extremely topical because just today Elaine Murakami called to remind me that i need to get something written up regarding our survey of several trb committees regarding the content (tables) of the ctpp package. here is a web page that presents some preliminary work in that area. don did remind me of an early product that even we in chicago used (stf s-5). http://www.mcs.com/~berwyned/census/notes/content.html needless to say any comments folks have on content for the ctpp (the tables) would be appreciated. i also recommend that you post your comments to the list ed christopher ------------------------------------------------ Don, Let me see what I can answer right now and what has to go into the hopper: > Place of work outside SMSA of residence. This needs a further > breakdown. Our Cincinnati area is a 13 co. CMSA so the data for > "outside each pmsa" doesn't tell me if the worker is in the other > pmsa. Similarly, we are adjacent to the Dayton msa and I can't > tell if the workers are coming to or from there. The county and > major city breakouts in this table are also valuable. (CBD?) > These concerns apply mainly to the standard tabulations. I > strongly recommend that the STF-S-5 commuter tabulations > be prepared again for nation-wide county to county work > trip commuting. I actually depend on > these for my regional in and out commuting and, consequently, > the regional net employment. I think the work flows have to come from the county to county file, and I would assume that will be repeated. It will make sure it's on our list. Actually, I was never aware of it as a formally named product (STF5?) but I did have a copy of it for Michigan counties. The issue of grouping counties as areas on the CTPP has to be fought out within the transportation planning community. > Another issue is continuation of the non-motorized travel modes > of biking and walking along with working at home. (Assuming > that transit and carpool modes will be continued.) These are > becoming more important in our region as we deal with air > quality conformity, congestion reduction and sprawl. Bicycle, Walked, and Worked at home are on the census dress rehearsal questionnaire, which means that unless something very unusual and unlikely happens, they will be on the 2000 long form. Once the data are collected, it's really up to the transportation planning community to decide how they will be tabulated on the CTPP. Also, you are going to have more opportunity to do your own tabulations via the Internet, so if you need something special you will probably be able to do it (albeit for a fee), or pay someone to do it for you. > Finally, an issue that I am assuming will be fixed with the > 2000 CTPP is place of work coverage in the suburban > and rural areas of our metro area. In 1990, less than half > of a county's workers were 'assigned' to a TAZ of work > in three of the 8 counties in our MSA. With nationwide TIGER coverage, I believe that all workplaces with street addresses are to be coded to tract/block. This of course permits their assignment to TAZ. The question is what happens with the inadequate workplace address entries on the census. You might want to talk to Phil Salopek about their plans on this. In 1980 Phil Fulton devised an elaborate allocation algorithm which fixed a lot of the problems in these data for workplaces inside the urbanized area, and with the full TIGER coverage the algorithm can be run for everywhere. However, if you have some major workplaces in the more rural counties that don't have addresses and that you want to be sure are coded correctly, you may be able to provide some workplace name information to the Bureau to assist with this. > And that brings to mind another final issue. In 1990, our CMSA > and MPO included the same 8 counties. In 1993, five more > counties were added to the CMSA, but not to our MPO > planning area. Therefore, our 2000 CTPP > will not include the added CMSA counties. Does this matter? The CMSA and the MPO don't have anything to do with each other, really. The CMSA is defined under OMB rules (now under review for possible significant changes; a federal register notice is due very soon); there can be a considerable amount of politics in the MSA/PMSA/CMSA designations because a lot of people think "the bigger the better" which makes for larger CMSAs. If you're not planning for the additional 5 counties, you probably don't need the CTPP for them. Besides, won't some other MPO have it (if the 5 counties are their own PMSA, they probably have some MPO coverage somewhere). > Thanks for asking! Hope this helps! > (copied to Ed Christopher) Ed, if you want to post this to the list, please feel free. ============================= Patricia C. (Patty) Becker 313/535-2077 APB Associates/SEMCC FAX 313/535-3556 17321 Telegraph #204 Home 248/355-2428 Detroit, MI 48219 pbecker(a)umich.edu

26 years

Mailing list

by Frey-DPW, Bob

Greetings Ed Christopher: Please place me on the CTPP e-mail list server so I can contribute to it and view others correspondence. Thanks, Bob Frey Massachusetts Highway Department bob.frey(a)state.ma.us

26 years

CTPP

by Nathan Erlbaum

At Ed Christopher's suggestion I am posting this to the list server. The following are some observations on the E-mail traffic I have been observing with respect to the CTPP summarization issues that I have raised with Ed at and since his sub-committee meeting at TRB last January. I must note that more recent e-mail is now starting to mention non-TAZ needs Phil Salopek in a recent e-mail says if you want Census geography instead of TAZ you don't have to participate in the TAZ up program....well at NYSDOT we want the statewide element of the CTPP to be detailed to CDP or lower and all the urban area elements for our use to be detailed to Census geography....tract and block group as the lowest level in the urban area. NYSDOT is interested in Census geography at the block group level especially in urban areas. Since each of the MPOs will be responding separately to the CTPP TAZ questionnaire, in addition to NYSDOT, then MPOs will indicate their need for TAZs or census geography. This way the MPOs can get what they want and the state can get what it needs. The glitch is if Census or Phil Salopek says the state has to have it the MPO way. Frankly I don't see the problem....the CTPP is part of the STF3. As part of STF3 it is summarized for CTPP parts A and 1 to the block / block group level and everything above from the get go. All that is required is the production of STF3 for the work place. County work flow is produced very early on in Census processing prior to the CTPP. These data are historically available on the REIS CD. So for the most part Census provides CTPP part C or 3 at the county level outside of CTPP. Clearly they have the routines in place to do it by specifying lower geography with selected focus (such as state or metro area). So its not just a CTPP processing software issue. The real issue is getting Census to recognize several things: 1 Census geography should always be available as a summarization level for all locations 2 If you are not an urbanized area 50,000+ then you likely do not have an MPO, and you do not have TAZs even though you may be a small urban area 3 TAZs are unique to "MPOs with models" and they don't define TAZs them the same way 4 If you are not now an urban area now and eventually become one in say 2002 then you are out of luck if TAZ is the only summarization level. This may be especially painful when we move to the ACS. 5 If you need to add TAZs , combine or subdivide them later you can't 6 This is not just an MPO product 7 This is really a summarization level issue like congressional boundaries 8 The problem that Census really needs to address is how to aggregate data up from lower geography for values such as mean and median; where summarization is really not possible ( median income or median travel time for example). Resolving this problem then enables Census or the end user to create the data at the lowest possible geographic unit and provide a summary level routine for computational values. All the MPOs need then is a simple lookup table to relate TAZs to Census geography and a routine to fix the computational values 9 From a purely economic product perspective Census geography means you can sell the product to third parties and recover the cost. TAZ is a summarization level unique to MPOs. There are lots of value added resellers of STF3 data now in addition to Census. The CTPP creates the workplace version of STF3 for a number of measures that are important to not only transportation planners but also to anyone interested in who, how and/or what arrives at work place locations. 10 Remember to make sure that the CTPP coding uses Census FIPS codes and not Census Place codes that Caliper used in 1990, otherwise it will not directly match common tiger based coverages. 11 The CTPP software that extracts the data table components from the CD rom needs to be improved on the data extraction part. Often one wants some range of Fips or town county, state codes for either the residence , work place or JTW and for selected fields (e.g. total trips, transit). As the 1990 CTPP software works you get all geography that you can point to on the map, not bad on the statewide side except if you want trips from selected origins outside the state. If you are using the urban element then selection is much more difficult because of the level of detail. In either case JTW from selected to selected geography is not easily do-able except in a database product. Some accommodation on the direct data selection side rather than through the visual graphical user interface would be helpful. Something like "extract" the Census routine for use with the Census STF CDs would be helpful. Otherwise you really need a database product like SAS, Paradox, dBASE or Access to get at the data the way you want. 12 What would really help would be Census creating STF3 for the workplace and the present county work flow data for lower summarization levels 13 Lastly it might be useful to note that at NYSDOT many of the information requests I receive come from the economic development interests. These requests reflect transportation or government concerns for attracting businesses into NYS. They come from within our agency or from our State Economic Development agency. These questions typically ask about workers first and then where they live. NYS can't be that different from the rest of the states that compete for the location of new jobs. Many of these requests are for areas just outside of the urban boundary. The fact that these type of informational questions are being asked illustrates the value of detailed Census geography and summarization levels beyond what has been provided for at the metropolitan planning through TAZs. As always I am available to discuss some of the more mechanical technical aspects of using the CTPP data in non TAZ analyses with anyone who wants to discuss why one size does not fit all.

26 years

Development of TAZs for the 2000 CTPP (From Thabet Zakaria)

by Margaret Shaw

The following message is from Thabet Zakaria <DVRPC>, not from Margaret Shaw. Please direct all correspondence regarding this mailing to Mr. Zakaria, NOT to Ms. Shaw. Mr. Zakaria's e-mail address is: tzakaria(a)dvrpc.org Thank you. Development of TAZs for the 2000 CTPP This is a brief description of the Traffic Analysis Zones (TAZ) in the Delaware Valley Region, which includes an area of 3,833 square miles and a population of about 5.2 million. I have prepared this summary in the hope that other areas in the country will find it useful for preparing a zonal system for the 2000 CTPP. In 1960, the Penn Jersey Transportation Study developed a set of TAZs for data collection and travel simulation within the cordon area (urbanized area) which did not consider county boundaries. The basic unit was a modified grid square, 0.10 mile on a side in city centers and 0.50-mile elsewhere. A total of 162 districts (TAZs) were aggregated to 51 Superdistricts for evaluation and presentation. In the late 1970s, DVRPC realized that it could not continue to collect massive data for transportation planning, and must depend on secondary sources, including the Bureau of the Census. It was decided to adopt census geography and convert the old TAZs to census tracts and block groups. Census tracts were considered adequate for regional travel simulation, except for the Philadelphia CBD, where block groups were used to define TAZs. The cordoned area was expanded to the region's county boundary and divided into 1,330 TAZs, which were aggregated to 71 county planning areas to simplify analysis and presentation. This system of TAZs was expanded in the 1980s, because the Bureau of the Census in cooperation with the counties divided some census tracts for the 1990 Census. This system proved to be easier to work with and facilitated the preparation of a correspondence table for the 1990 CTPP between TAZs and blocks. It should be noted that the new TAZ system is not free of problems. Some tracts are too large or too small for network coding and modeling, and they must be reviewed each decade because of tract splitting. Also, some tracts are too narrow or curvilinear, and are thus not suitable for travel simulation purposes. It is essential that each tract in the area be examined regarding its layout, size, type and magnitude of development. Several criteria could be used to develop TAZs form census geography, such as population, employment, trip production, trip attraction, zone centroid location, and trip loading (network grain). DVRPC used an average of about 4,000 persons and 3,000 employees per zone in the development of its TAZ system. Obviously, the size of TAZs should be smaller for corridor and sub-area studies and small MPOs.

26 years

NAICS data user conference-FREE!

by Murakami, Elaine <FHWA>

I recently got a flyer for this one-day conference. What will it cover: Background, structure, content, and new products and "why NAICS is better" The good news is that it is FREE and includes lunch. The bad news is that it is on January 14, 1999, 8:30 a.m. to 4:00 p.m. which conflicts with TRB. It is here in Washington, D.C. at the Reagan Building, near the Federal Triangle Metro stop. You MUST reserve a space by responding to the Census Bureau at FAX 301-457-1343. For questions, please call Jeanette Mon at 301-457-3126.

26 years

Re: CTPP 2000 TAZ Update Program

by phillip_a_salopek＠ccmail.census.gov

Bob: I will attempt to answer your questions, and distribute my response to you, to a number of individuals, and to the CTPP news group on the off chance that others may have similar concerns. Here goes. 1) The effect of participation in the TAZ update program on the CTPP data that will be available is simple. If you want any TAZ level data out of the 2000 CTPP, you must participate in the TAZ update program. If you want CTPP data only for standard census geography, either tracts or block groups (you choose which one), then you don't need to participate in the TAZ update program. You asked about CTPP data available on the Internet. Right now, we don't know if there will be any CTPP data available over the internet. We are currently discussing the design, content, products, etc. of the 2000 CTPP with DOT. (For general information and updates you might want to join the CTPP news group, ctpp-news(a)chrispy.net. Instructions for subscribing may be found at the URL http://www.mcs.com/~berwyned/census. Note that there is lots of other interesting stuff presented there, courtesy of Ed Christopher of the Chicago Area Transportation Study and others.) Anyway, what we do know is that there won't be CTPP data, nor any commuter flow data, nor any specific workplace data, available through the Census Bureau's decennial web access, once called the Data Access and Distribution System (DADS) but now known as the American FactFinder. Flow data, or any data tabulated by workplace instead of by residence, has been determined to be out of scope for American FactFinder. In our discussions with DOT we have outlined a 2000 CTPP that would consist of a Statewide Element and an Urban Element. Each element would contain a set of residence-based tables, a set of workplace-based tables, and a set of origin by destination tables. These sets of tables will be standard for all areas. Our assumption is that for a whole state in the statewide element or for an MPO area in the urban element, the volume of data would be too great to ask people to download it over the net. So we think we will distribute the 2000 CTPP on CD (or some other high capacity medium) again. This time, however, we will provide the access software ourselves and deliver just one integrated product, data and software at the same time. However, DOT has indicated (and I agree) that it would be nice to be able to have some kind of data on demand system available for CTPP customers over the net. But this is still just an idea at this point. We don't know if it's feasible, how expensive it would be to develop, how it would work, etc. We'll try to keep people posted on the status; right now we've agreed to look into what it would entail, but have not promised to provide such functionality as part of the CTPP. 2) I'm not the best person to ask what standard geography will be available from American FactFinder. I'm not sure the decision has been made yet. I would guess that you'll be able to retrieve anything that has been released on a summary tape file. This would imply that you could get individual data items for tracts and block groups of residence. It sounds like there may be some multi-variable crosses that will be available for tracts, but not for BGs (too much detail for the finer geography). In general, there could be some differences like this in what data are available based on the size of an area, but I think this would be the only criterion. As I noted above, there won't be CTPP data available, nor any flow data, nor data by place of work from American FactFinder. There will probably be recodes like worked in same county, diff. county, diff state, etc. I don't know what the current plans are for data on demand over the net through American FactFinder. They might accept specs for custom tallies from PUMS, but this would be for large geographic units. I don't know if there will be any facility for doing custom tables from the full sample (i.e., not PUMS). Even if you wanted TAZ of residence only (no flows or at-work data) I don't know if TAZ is a piece of geography that will be supported. It could be, because we intend to provide it on the internal files we use for tabulations, but that doesn't mean they'll make it available over the net on demand. I see on the Census web site that questions about 2000 are supposed to be directed to 2000usa(a)census.gov. You could try this and see what you get. I'd be interested in seeing their reply. 3) If an MPO does not participate in TAZ-UP, we will ask them to choose tracts or block groups as their smallest geographic unit in the 2000 CTPP. 4) I'm not sure I understand this question. In the Urban Element, the MPOs choices are taz (if you've participated in TAZ-UP), tract, or BG. You'll have to pick one. 5) Our assumption so far has been that MPOs will have the choice described above for urban element geography. This would only cover the counties situated in the MPO areas. However, all counties would be included in the statewide element and there would be summary levels for counties and places of say 2,500 or more residents in the statewide element (as in the 1990 CTPP). Massachusetts (as well as some other New England states) may be an exception in that the whole state may be covered by MPOs (RPAs in Mass) and therefore the whole state may be included in the urban element at the taz, or tract, or block group level. 6) The Census Bureau's policy is that the most detailed level of geography we will show for sample (long form) data is the block group. That is why MPOs can choose between BGs and tracts for their CTPP. In the past we have treated TAZs as BG-like units and provided sample data for TAZs in the CTPP as well. There seems to be more concern for 2000 within the Census Bureau that BGs, and by implication BG-like units, may be too small to support some of the large (in terms of number of cells) tables created for them in the past. 7) Again, I'm not sure what you are asking. In standard census data products like STF3A on CD-ROM the entire hierarchy is available, from Block Group to whole state totals. In printed reports, totals for places above some size cutoff are usually available. There have also been printed data available in the past for census tracts by residence, but I don't know if that will happen for 2000. In the CTPP, you pick one of the three as your most detailed level. 8) Even if an MPO, or region, or county used TAZs in the 1990 CTPP and those TAZs were inserted into TIGER, and they think they don't want to make any changes to the boundaries, they still have to participate in the TAZ-UP program if they want TAZ data from the CTPP in 2000. It is entirely possible that some of the lines used as TAZ boundaries in 1990 will not be available for use in 2000, so boundaries will need to be adjusted. But in addition, for 2000 there will be many more lines that will be eligible to be used for TAZ boundaries, since MPOs won't be constrained to build them up from census tabulation blocks. This means it should be easier for the MPO to approximate the true TAZ boundaries than it has been in the past. Sorry this has run on so long. Please call me at (301) 457-2454 if I've missed the boat and failed to clearly answer your questions. --Phil ______________________________ Reply Separator _________________________________ Subject: CTPP 2000 TAZ Update Program Author: "Frey-DPW Bob" <Bob.Frey(a)state.ma.us> at SMTP-GATEWAY Date: 11/30/1998 3:36 PM Hello Phil: Bob Frey from the Massachusetts Highway Department here. We have had several discussions concerning CTPP in past years, and I'm hoping you can help again. Todd Blair suggested I contact you to get some further clarification regarding the TAZ Update program: 1) Will TAZ update participation status have any effect on what CTPP data will be available on the internet, or will a standard set of reports be available for all areas? 2) And what standard census geography will be available on the internet, and does this differ depending on the area? 3) If an MPO choses not to participate in the program, what is the default delineation for 2000 CTPP data (census tracts, block groups, or 1990 TAZ boundaries)? 4) In this situation, would block groups be available to every area anyway? 5) If not, will the CTPP data be available only to the level of tracts for rural areas, and down to block groups for urbanized areas? 6) Exactly what determines the lowest level of census geography available for the data in a given region? 7) Program participation aside, how can I determine what will be available throughout Massachusetts in terms of tracts/block groups? 8) If a region/county wants to keep their 1990 TAZs without changes, do they still need to participate in the TAZ Update Program to confirm this? If you could get back to me soon by phone or e-mail I would greatly appreciate it. Thanks, Bob Frey MassHighway Planning (617)973-7449 bob.frey(a)state.ma.us

26 years

TAZs and BBSP (Block Boundary Suggestion Program)

by phillip_a_salopek＠ccmail.census.gov

____________________________ Forward Header ________________________________ Subject: 2000 CTPP TAZ-UP Author: Don Burrell <DBURRELL(a)oki.org> at SMTP-GATEWAY Date: 11/25/98 5:12 PM The Journey-to-work and FHWA folks are currently working on a program to prepare the CTPP TAZ geography in advance of the census, specifically by next summer. This is to be done using a program called TAZ-UP, TIGER/Line 99 and ArcView GIS software. Today, I shipped the results of the 2000 Census Statistical Areas Review process for 2 of the Cincinnati area counties to the Detroit regional office. This work, which is underway throughout the country, has identified census tract and block group boundary changes to be used for the 2000 census. Having just now put 2 + 2 together, my question is whether or not the Bureau will have our new local recommendations for census boundary changes in the TIGER/Line 99 file that is to be shipped to us for the TAZ-UP work? OKI plans to revise many of our TAZ boundaries to conform to the 2000 census geography. It would be helpful to have the 2000 census geography shown. Don Burrell OH-KY-IN Regional Council of Govmts. ____________________________________________________________________________ Response from P. Salopek Don: I could not answer this question on my own, so I spoke with Bob LaMacchia in Geography Division of the Census Bureau. The first point is that for the TAZ-UP program, TIGER/Line 98 will be the base, not T/L 99. T/L 98 will NOT include the local recommendations for block boundaries that you just submitted. Bob L. says that the verification phase for both programs will occur at the same time. This means that the T/L 99 that I guess participants in both activities will receive to review will contain both the new TAZ boundaries and the new block boundaries (collection blocks, not tabulation blocks). One point to remember is that in defining TAZs for 2000 you will not be constrained to build them from blocks, since blocks won't be defined yet. You will in fact have a wider array of lines/features to use as TAZ boundaries than has been available in the past. We think this is an improvement and should allow closer approximation to true TAZ boundaries. --Phil

26 years

NEWS ALERT

by ed c

December 4, 1998 Supreme Court Weighs Legal, Constitutional Issues in Census Sampling Cases Justices Question Role of Judiciary in Settling Sampling Dispute Monitoring Board Reviews Use of Administrative Records in Census The United States Supreme Court heard oral arguments November 30 in two lawsuits challenging the use of sampling and statistical estimation in the census. The Justices heard presentations from Solicitor General Seth Waxman, arguing on behalf of the Administration; Maureen Mahoney, with the firm of Latham & Watkins, representing the U.S. House of Representatives; and Michael Carvin, with the firm of Cooper, Carvin, & Rosenthal, representing Matthew Glavin and other private plaintiffs. The Court had agreed to consider both cases after two separate three-judge district court panels ruled earlier this year that the Census Act prohibits sampling to derive the population counts used for congressional re-apportionment. Some highlights of the hearing in the cases of U.S. House of Representatives v. U.S. Department of Commerce and Glavin v. Clinton: * Several Justices were skeptical about the legal authority of the House of Representatives to sue the Executive branch to force a particular action that Congress could not bring about by enacting a law. Justice Scalia said that the Judicial branch should not be asked to resolve a political dispute between the other two branches. He prompted laughter by suggesting that Congress could threaten to withhold funds for the census or even White House operations until the Administration agreed with its position on sampling. * There was less discussion about the legal standing of individuals and counties to file suit in the Glavin case. However, there was some confusion about whether these private parties must show that their States were likely to lose a congressional seat if sampling were used, in order to establish probable harm or injury from the Census Bureau's plan for 2000. There was also confusion over whether critics of the Bureau's plan believed that the law and Constitution barred sampling only for congressional apportionment or for other purposes as well. Justice Ginsburg noted that the use of sampling to produce census numbers for redistricting and the allocation of Federal aid was not an issue before the Court. However, Ms. Mahoney argued that sampling could not be used to count the population for any purpose, including congressional redistricting and Federal funds distribution. The Secretary of Commerce's authority to use sampling in taking a decennial census, she said, is limited to the collection of demographic and economic data on the traditional long form. * The Justices appeared to be divided about whether sampling and other statistical methods could be used to improve a direct counting effort. Justice O'Connor said that most people would think that the words "actual enumeration" in the Constitution meant a one-by-one count. She later challenged the House counsel's description of the Census Bureau's plan as an effort to count only 90 percent of the population, noting that 100 percent of households would receive a census form. Justice Stevens asked what census takers would do if there were a building with many undocumented residents who were afraid to answer the door and provide information. In the face of evidence that people lived there, must the census taker write down "zero," the Justice asked, even though "one" would be closer to the truth? Ms. Mahoney said that the count for those households must be "zero," which she said was preferable to guessing, prompting Justice Breyer to ask whether that was the policy even if the lights went on and off at night. Many observers believe the Court will issue a ruling by next spring; technically, the Justices have until the end of the term (late June or the beginning of July) to reach a decision. Monitoring Board examines administrative records: The Census Monitoring Board debated whether administrative records could be used to reduce the disproportionate undercount of racial minorities in the 2000 census at a November 23 hearing at Census Bureau headquarters. Republican co-chair Kenneth Blackwell said in opening remarks that he believes the Bureau can use Federal, State and local program databases, such as Medicaid files, to add targeted, hard-to-count populations to the census. Dr. John Czajka, a member of the National Academy of Sciences panel reviewing census methods, was the only non-Bureau witness. Dr. Czajka discussed the quality and content of government databases, and said records must be pulled from many sources in order to compile the basic information collected in the census. For example, tax returns and other information maintained by the Internal Revenue Service could be linked with social security records to gain more demographic data. Dr. Czajka said that further research was needed to overcome several deficiencies in the data from administrative databases that make their use problematic for census purposes. Those problems include the lack of a physical address (e.g., a post office box); the time lag between point of collection and Census Day; the inclusion of people who have died or the omission of recent births in some record sets; and missing demographic variables needed for the census (such as race, marital status, and relationship of householders). Databases also are most likely to leave out young people in their late teens and early twenties and noncitizens, he noted. Dr. Czajka concluded that administrative records could not be used to add people to the 2000 count. Three previous efforts to rely on such records to add to the census "blew up on the launch pad," he told the Board. He urged the Census Bureau to spearhead a research effort to address deficiencies, as well as privacy and confidentiality issues, and also noted that current law may prohibit the disclosure of some records for census purposes. Senior Census Bureau staff testifying before the Monitoring Board said that the Bureau would have to verify the information contained in administrative databases before adding those people to the census count. They noted, for example, that about 16 percent of all Americans move each year, while much higher proportions of harder-to-count groups like renters change residences, making field verification of administrative records necessary. The Bureau plans an extensive research effort to determine if government databases can be used to count the population in future censuses, the staff said. Bureau Director Kenneth Prewitt said the agency is not opposed to using administrative records in the census. "The bureau would use any method we thought would make the count better," he said. There were no witnesses supporting the use of administrative records to add people to the 2000 census. At the conclusion of the meeting, co-chair Blackwell said Republican Board members did not want the Bureau to rely on methods that haven't worked in the past if the Supreme Court "outlawed" sampling, and they urged the Bureau to pursue the use of program databases to address the differential undercount. The Board's next hearing is on December 16 in Sacramento, CA, one of the three dress-rehearsal sites. Census Advisory Committee considers recommendations: At its last meeting of the year, members of the 2000 Census Advisory Committee reviewed a draft of the panel's final report, which it will present to the Secretary of Commerce next February. The report will include key recommendations on the importance of partnerships with local governments and community-based stakeholders, effective field operations, the use of scientific and statistical methods, and the availability of census data products. Administrative note: You can find an archive of recent and past News Alerts at the Census 2000 Initiative Web site, www.census2000.org http://www.census2000.org. Questions about the information contained in this News Alert may be directed to TerriAnn Lowenthal at (202) 484-2270 or, by e-mail at terriann2k(a)aol.com. Please direct all requests to receive News Alerts, and all changes in address/phone/fax/e-mail, to Census 2000 at Census2000(a)ccmc.org or 202/326-8700. Please feel free to circulate this information to colleagues and other interested individuals.

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