Re: [CTPP] New Website--Old Data

Hi Ed: The 1970 Census data on the BEA website shows a separate row, at the very end of each county's table, for "place of work not reported". So, Cook County Illinois has 181,911 resident workers with place-of-work not reported, in 1970. Part of the mystery is solved. I believe all of the "standard" 1970 Census tabulations did NOTdo place-of-work allocation (imputation), so we would always see the "not reported" data for any county, place or tract. The 1970 Urban Transportation Package (UTP) probably had some allocation (imputation) procedure to allocate the "not reported" area-of-work to whatever geographies were used after the 1970 Census. This is a guess. I don't have extensive records of the 1970 process. [I do have the "Urban Transportation Factbook" published by the American Institute of Planners and the Motor Vehicles Manufacturers Assocation, in 1974, but it appears to be based on standard census tabulations, not the UTP....?] Perhaps the answers are hidden in the Census Bureau (maybe Phil can find the info before he retires next Friday? Or perhaps the answers are in the archives - - JJ McDonnell's papers, or Alan Pisarski's office....Perhaps some information is in the TRB Special Report #145 (the 1973 Albuquerque Census conference.) Happy hunting, Chuck ************************************************************** Charles L. Purvis, AICP Principal Transportation Planner/Analyst Metropolitan Transportation Commission 101 Eighth Street Oakland, CA 94607-4700 (510) 817-5755 (office) [new, 8/1/05] (510) 817-7848 (fax) [new, 8/1/05] www: http://www.mtc.ca.gov/ Census WWW: http://www.bayareacensus.ca.gov/ ************************************************************** Our friends (who I do not know) at the Bureau of Economic Analysis who do the Regional Economic Accounts revamped their historic (1970, 1980, 1990 and 2000) Journey to Work (JTW) data base and put a nice search engine to it. For years I have sent people to the BEA sight for JTW flows but with the new search engine and the 2000 data it is so easy to use. For 2000 they have added flows by major industry at the county level and by minor industry at the state level. You really need to check it out. http://www.bea.gov/bea/regional/reis/jtw/ But then there is the nagging issue. Why do my historic CTPP/UTPP numbers and BEA not match. In 1970 and 1980 the two sources look to be off in different directions, but for 1990 they match and for 2000 it looks like a small rounding difference. Getting into the detail, attached is a comparison of the BEA/CTPP-UTPP numbers for Cook county IL, specifically the Cook to Cook flows. In 1980 BEA is about 2K higher out of 2M, but in 1970 BEA is in the neighborhood of 200K low. I know this keeps coming up, but why? Is the pattern the same around the country, BEA is high in 1980 and low in 1970? At some point we may need to reconcile all this and pick one series or the other. Since I have been tracking the Chicago region numbers (http://www.berwyned.com/papers/co2cochgo.pdf) for quite some time this has always been a nagging headache. How do all the numbers compare in your counties? Does anyone remember why the 70s and 80s might not match? (please reply to all) -- Ed Christopher 708-283-3534 (V) 708-574-8131 (cell) FHWA RC-TST-PLN 19900 Governors Dr Olympia Fields, IL 60461 _______________________________________________ ctpp-news mailing list ctpp-news(a)chrispy.net http://www.chrispy.net/mailman/listinfo/ctpp-news