Re: [CTPP] CTPP Update

From a small (~135,000 pop) MPO perspective, the implications of these super-TAZs for travel demand modeling are devastating. If 65K, we would have two TAZs; if 20K, we would have six or seven. Fortunately, we are also an attainment area and are not mandated to do modeling at all; however a new TMA with population of 200,000 would be so mandated and would have a total of three or 10, respectively, so it would become virtually impossible to do modeling for AQ conformity.

If we create "super" tazs with populations of 20,000 and/or 65,000, would we be able to get tabulations for such areas? Larry G. Mugler, AICP - Planning Services Manager 303-480-6759 - Customer Resource and Support Denver Regional Council of Governments -----Original Message----- From: ctpp-news-bounces(a)chrispy.net [mailto:ctpp-news-bounces@chrispy.net] On Behalf Of Murakami, Elaine Sent: Wednesday, June 11, 2008 12:43 PM To: ctpp-news(a)chrispy.net Subject: RE: [CTPP] CTPP Update Re: poverty and Income comparisons between Census 2000 Long Form and ACS: The only report I am familiar with is: http://www.census.gov/acs/www/Downloads/Report05.pdf Pages 34-37 discuss county-level comparisons. These are comparisons between the Census 2000 Long Form (aka sample) and the ACS "C2SS", and 18 of the test ACS counties. They found that the C2SS results consistently had lower incomes than the Census 2000 sample, and therefore, a higher poverty ratio. They found that income allocation occurs 30 percent in the Census 2000 sample, and 24% in the C2SS. I do not know if the Census Bureau has pursued other research on how ACS respondents answer the income questions. Elaine -----Original Message----- From: ctpp-news-bounces(a)chrispy.net [mailto:ctpp-news-bounces@chrispy.net] On Behalf Of Ed Christopher Sent: Wednesday, June 11, 2008 9:50 AM To: ctpp-news maillist Subject: [CTPP] CTPP Update On May 21 and June 4 members of the CTPP team conducted a series of webinars to help bring our community up-to-speed on several of the CTPP activities. The slides from these presentations can be downloaded from our webinar room at http://fhwa.acrobat.com/ctpp1 (enter as a guest) and the responses to many of the questions asked during the meetings are presented below. If folks have additional questions please feel free to post them to the list serve and someone on the CTPP team will attempt to answer them. CTPP Webinar - Questions and Answers Question: Will the 3-year CTPP data product based on ACS include tables by race and household income? Response: Yes but the best source for information on race will still be the Census Bureau's standard ACS tabulations found on American FactFinder (http://factfinder.census.gov/). The 3-year CTPP proposed tables for parts 1 and 2 include a few tables with the variable "minority status." Also, there are various tables with the variables - Income, Poverty Status and Worker Earnings that will be available. Please note that Poverty Status is a calculated variable based on household income, family size, number of children and number of family members over the age of 65. Question: Since the new CTPP products will be based on data collected over 3 years (or 5 years), to which year will the income be adjusted? Response: Income will be adjusted to the last year of the survey period. For the first 3-year product all incomes will adjusted to 2007. Question: Is there data available on zero car households? If yes, what geography level is it available? Response: Yes, there will be information available for zero car households in both the 3-year CTPP data product and as part of the standard Census products. The data will be available for geographic areas greater than 20,000 residents. Question: Slides 6 & 7 of the DRB presentation show different percentages of data lost due to DRB rules, why is that? Response: Slide 6 showed the number of workers lost while slide 7 showed the number of origin-destination pairs lost. The point is that when thresholds were applied to CTPP Part 3 data as was the case with the 2000 data, many folks looked at the loss of workers as being significant but more surprising was actual loss of individual O-D pairs. All in all table thresholds devastated the part 3 flow data. Question: 2005 ACS data doesn't have information on Group Quarters, but the 2006 and 2007 do. How is this being handled in the 3-year 2007 ACS products? Response: The Group Quarter data available for 2 years (2006 and 2007) will be reweighed to account for the missing year. Question: Will the variable - Means of Transportation to Work have walk and bike modes combined? Also, what about taxi, bus and other? Response: Regarding the 3-year CTPP data product there are multiple category lists for the variable - Means of Transportation to Work. There are a few tables all 17 modes plus the total are shown separately but then there are many others where walk and bike have been collapsed together. A great deal of the detail on the mode variable is in the hands of the Census Bureau's disclosure Review Board. Currently they have proposed some very tight restrictions on the proposed 3-year CTPP tables. Please see http://trbcensus.com/drb/ for more Question: Do you have anything on the TAZ definition timeframe that you can share with the group? Response: Please see our Status Report newsletter for the latest http://www.TRBcensus.com/newsltr/sr052008.pdf. Question: Can you talk about the difference in income between ACS and Long Form? Response: In Census 2000, the question was asked during April for the previous year, 1999. Because April is so close to IRS annual return data it was felt that "good" income data was being collected because it was fresh in people's minds. However, for the ACS the same questions are asked, but the respondent could be getting the survey during any month of year (depending on when she/he received the form). This reported income is then adjusted to the current year (year of tabulation) based on CPI. There are several issues with this with the largest being that at anytime during the year most people do not how much money they made in the last 12 months. Needless to say the income question is messy. Question: Poverty rates seem discontinuous, higher. Any ideas why? Response: Yes, they are discontinuous. Hopefully they will look better with the 3-year ACS data products. Question: If the DRB is so strict with its rules then why bother with new TAZs? Response: We hope that the DRB will relax its rules but having TAZs that correspond to the ACS data release products (65,000 pop TAZs, 20,000 pop TAZs and small TAZs) will help us in the future all sorts of data products. Having geography match the data release seems to make good sense so that we can at least get complete coverage (wall-to-wall) within a region. Question: What are the implications of rising fuel prices on travel choices on mode to work? Has anybody thought about it, especially with aggregating 3 years worth of data? Since the ACS asks about "usual" mode, it could still miss modes used only part of the time. Response: The 3 year ACS trend data might look a lot different than the 2000 data. This might be a good research question. Question: Is the category list for the variable - occupation being consolidated? Response: No, DRB has not asked us to collapse the variables - industry or occupation. Question: Is anybody planning to write to Congress about the DRB issue? Response: AASHTO SCOP is sending a letter to the Census Bureau to appeal the DRB decision. As FHWA staff, we cannot contact Congress directly but we know that many regional agencies do talk with their Congressional delegations. It is somewhat ironic but many of the congressionally mandated analysis like the FTA New Starts program and environmental justice analysis all need data at a smaller geography level which will be difficult to obtain with the DRB's current rules. Question: We are relatively a new MPO and I have a CTPP 101 question. As an MPO do we need to provide you any information, and what are our sources of information regarding CTPP specifically regarding TAZs? Response: The CTPP listserve is a good place for information regarding ongoing CTPP related activities. The TAZ definition process is planned for March/April of 2009 and it is recommended that MPO's allocate some budget when preparing their work plans for FY 2009, especially for new MPOs. The CTPP Status Report is also a good source of information. If you have any particular questions please do not hesitate to contact anyone one of us on the CTPP team. Question: Somewhere it was noted the first CTPP ACS product would be available in 2009 for areas of 20,000 or more for places and counties. Response: Yes that is correct. We are still in the negotiation stage regarding some DRB issues but this is our GOAL. This first CTPP product would use 3 years of ACS data. Question: There was also a mention of TAZ level data also for 20,000 population threshold. However, I am not sure if this is included in the first 3 year product for 2009, or whether the first TAZ level report will not be available until 2012 with a 5 year product. Response: To get "small" area geography like a TAZ or a census tract, the census requires 5 years of ACS data. So, we are planning to wait for 2006 thru 2010 ACS data to incorporate 2010 Census geography and weights, which we hope would be tabulated by 2012. This will likely require some data synthesis before release. Because of the probability that the data will be synthetic, we do not anticipate any population threshold. -- Ed Christopher Resource Center Planning Team Federal Highway Administration 19900 Governors Drive Olympia Fields, Illinois 60461 708-283-3534 (V) 708-574-8131 (cell) 708-283-3501 (F) _______________________________________________ ctpp-news mailing list ctpp-news(a)chrispy.net http://www.chrispy.net/mailman/listinfo/ctpp-news _______________________________________________ ctpp-news mailing list ctpp-news(a)chrispy.net http://www.chrispy.net/mailman/listinfo/ctpp-news _______________________________________________ ctpp-news mailing list ctpp-news(a)chrispy.net http://www.chrispy.net/mailman/listinfo/ctpp-news