Project 3 Spatial Analysis of Demographic Data 4/10/2008 Due date: April 113. 2000 Demographics5. Project 3 Requirement6. Download data from server7. Set Up Geodatabase For Data8. Bring in Spatial Data for Tracts9. Bring in the Attribute Data for Tracts2000 Attribute1990 Attribute10. Compare the Data in ArcMap2000 DataOpen the attribute tables for Tgr48085trt00 and Col_tr20001990 DataOpen the attribute tables for Tgr48085trt and Col_tr199011. Establish 1990/2000 Tract EquivalencyNeed to add variable to 2000 tracts which indicates its 1990 tract equivalency. We then dissolve on this 1990 tract equivalency variable to reduce the 2000 units to 1990 units, thus achieving comparability.(Yes, there is already a variable there which does this: tr00_90! We will look at ways to create it.)1. 4-Digit Tract Code Approach2. Manual Editing Approach3. Spatial Join Approach using Polygons4. Spatial Join Approach Using Centroids12. Join the 2000 Attribute Data to Tract Spatial DataIf necessary, bring in the attribute data for 2000 (col_tr2000)13. Dissolve the 2000 Data into 1990 Tracts14. Join the 1990 Attribute Data15. Calculate Change Variables and Clean Up16. Making Comparisons Using Area Allocation (“Union” approach)For Census TractsAnalyzing Block Group DataAnalyzing Block DataAppendix A—Obtaining Centroid For Polygon File Using ArcMapProject 3 Spatial Analysis of Demographic Data 4/10/2008 Due date: April 111. 1990 and 2000 GeographicsWe will use the block, block group and census tract levels of geography. Spatial files for these (along with other layers such as roads) are provided in the TIGER2000 data distributed by the Census Bureau.You can obtain the raw TIGER files, and then use ArcToolbox to process them, at: http://www.census.gov/geo/www/tiger/index.html (for nation)http://txsdc.utsa.edu/txdata/tiger/ (Texas only)There are also conversion tools for TIGER-to-shapefiles, TIGER-to KML, and for census tables at: http://tnatlas.geog.utk.edu/downloadfree.htmAlternatively, you can go to ESRI’s web site and download the TIGER files already processed to shapefile format. In the class exercise, we will work with census tracts, but for the project you may need block and block group for 1990 and 2000.http://www.esri.com/data/download/census2000_tigerline/index.htmlThese same files are also available (Texas only) at:http://txsdc.utsa.edu/txdata/shapefiles/The following book may also have useful information:Alan Peters & Heather MacDonald Unlocking the Census with GIS. Redlands, CA: ESRI Press, 2004For those unfamiliar with these geographic units:Blocks: equivalent to a city block. The smallest unit (in land area) for which the Census Bureau publishes data. Data is limited to basic demographics (population, age, gender, ethnicity, etc) from the “full count” census forms. No socio-economic data e.g. income. Blocks are renumbered for each census, so Block 2345 in 1990 is not necessarily the same as Block 2345 in 2000, but an “equivalency table” is published. Because they are based on the road network, once the road network in a developed area is established, block boundaries are consistent from one census to the next. Block Groups: groupings of blocks. The smallest area for which socio-economic data available (although it’s limited). Block groups do not have consistent boundaries (or identification numbers) from census to census and are intended primarily fro Census Bureau data processing purposes. Tracts: combinations of block groups. Intended to equate to city neighborhoods and be similar in population (goal is 3,500, but can vary widely 0-20,000!). This is the smallest geographic unit for which extensive socio-economic data is published from the “sample forms.” Outer boundaries are intended to be consistent over time (although changes do occur) and use identifiable features of the landscape (roads, railroads, etc), with internal splits being used as population growth occurs. Numbering system is consistent over time and equivalency tables are published to identify splits and boundary changes. Census tracts can cross city boundaries (but not county boundaries), and data is usually published for each part of the tracts. BNA (Block numbering areas) are equivalent tocensus tracts in rural areas.These units “nest” as follows: blocks within block groups within tracts within counties.Note: tracts may be “split” by city boundaries.2. 1990 DemographicsThe file stf1BxTX.dbf contains 1990 demographic data down to the block level for the State of Texas. The folder DOCUMENT(1990) contains associated documentation. They were copied from the 1990 Census of Population and Housing Block Statistics, West South Central Division CD90-1B- US Bureau of the Census, Issued September, 1992 CD (Careful: 414,092 records!):See tbl.mtx.asc for identification of demographic variables in file.1The file stf3_1990_col_example.dbf is an example of Socio-Economic data from STF3 for Collin county by tract downloaded from the Census Bureau’s 1990 data extract system at:http://www.census.gov/main/www/cen1990.html (no longer available 2008 at tract level) Tables P1, P3, P80 and P80A were downloaded as a tab delimited file and converted to a dbf using Excel. Variables of interest are: income data [P08xxxx], plus populations counts for sample [P0010001] and complete count [P00030001]. All variable names can be found in the file 1990_STF_Tables.TXT in P:\…. Document(1990). Full documentation of STF3 is at the above site.3. 2000 DemographicsThe North Central Texas Council of Governments web site has tables (.dbf format) summarizing the 2000 census data from SF1 (basic demographics from questions asked of the whole population) down to the block level, and from SF3 (socio-economic characteristics derived from questions asked of a sample) down to the block group level. Go to the COG Web site for more details.http://census.dfwinfo.com/download.aspEquivalent data for all Texas is available athttp://txsdc.utsa.edu/txdata/sf1 (demographics)http://txsdc.utsa.edu/txdata/sf3/ (socio-economic characteristics)The comma delimited .csv files for each county are the easiest to process. Technical Documentation (600 pages of it!) is also available at this site. Data for the entire US (incl. the same DFW data as on the above sites) are at: www.census.gov,specifically: http://factfinder.census.gov/home/saff/main.html?_lang=en (select Decennial Census/get data, then Census 2000