1. Geographic Information Systems TIGER Data

2. 1 Street Unit ► Street segment ► Street segment - The range of addresses that run along a street from one intersection to the next intersection - The range of addresses that run along a street from one intersection to the next intersection ► Address range - The range between the lowest possible house number at one intersection and the highest possible house number at the other intersection - The range between the lowest possible house number at one intersection and the highest possible house number at the other intersection

3. 2 Census Units ► Census tracts ► Block groups ► Blocks

4. 2 (1) Census Tracts ► Defined by the U.S. Census Bureau for statistical reporting of demographic, economic, and other data ► The boundaries follow major streets or natural features ► Population in each tract is approximately 4,000 regardless of its size ► Census tracts are numbered consecutively and unique within the jurisdiction

5. 2 Census Units ► Census tracts

6. 2 (2) Block Groups ► Comprise a population of approximately 1,500 ► Boundaries coterminous with census tract boundaries

7. Block groups R Brancoto, SUNY Buffalo

8. 2 (3) Blocks ► Smallest geographic area formed by street segments ► Coded by a 4-digit number - The first one represents the block group - The last three are consecutive and unique within a block group - The last three are consecutive and unique within a block group

9. Census Units.. County Census tract Block group Block

10. 3. GBF/DIME Files ► Geographic Base Files (GBF) ► Dual Independent Map Encoding System (DIME) ► Dual Independent Map Encoding System (DIME) -A data format used by the U.S. Census Bureau to encode street network and related data for the 1980 Census. -It covers only the metropolitan areas - DIME was replaced by TIGER in 1990 census

11. 4 Vector (1) Non-Topological Structure Storing coordinates of two polygons: and Polygon x 1, y 1 ; x 2,y 2 ; x 3,y 3 ; x 4,y 4 ; x 5,y 5 ; x 1,y 1. Polygon x 1, y 1 ; x 6,y 6 ; x 7,y 7 ; x 2,y 2 ; x 1,y 1. (x1, y1) (x2, y2) A B 1 2 1 2 1 2

12. 4 Vector (2) Topological Structure Storing coordinates of two polygons: and Line 1 x 1, y 1 ; x 2,y 2 ; x 3, y 3 ; x 4, y 4 ; x 5,y 5 ; Line 2 x 1, y 1 ; x 5,y 5 ; Line 3 x 5, y 5 ; x 6,y 6 ; x 7, y 7 ; x 1, y 1 ; Polygon Line 1, Line 2 Polygon Line 2, Line 3 (x1, y1) (x5, y5) 1 2 1 2 1 2 Line 1 Line 2 Line 3

14. 4. TIGER ► Topologically Integrated Geographic Encoding and Referencing Files (TIGER) ► Developed by the U.S. Census Bureau for 1990 census ► The spatial and attribute processes were combined into one system ► A single seamless data set that covers the entire country ► Topologically structured

15. TIGER Geographic Features ► A combination of DIME and 1:100,000 Digital Line Graph ► Uses geographic coordinate system ► Two types of data: - a tabular form of demographic, social, economic - a tabular form of demographic, social, economic statistics statistics - a GIS form - a GIS form ► Aggregated information is available at the block group level, few at the block level

16. TIGER Geographic Features.. ► GIS data are available as both polygon data and line data ► The polygon data contain the population information in tracts, block groups, and blocks ► The line data contain streets and utility lines information ► The data have spatial locations, attributes, and topology

17. TIGER..

18. ► American Community Survey http://www.census.gov/acs/www/ http://www.census.gov/acs/www/http://www.census.gov/acs/www/ ► An ongoing statistical survey that samples a small percentage of the population every year ► 1-year, 3-year, and 5-year estimates http://www.census.gov/acs/www/guidance_for_da ta_users/estimates/ http://www.census.gov/acs/www/guidance_for_da ta_users/estimates/

20. 5. Applications of TIGER Data ► Address matching ► Network analysis ► District delineation

21. Address Matching (line data)

22. Address Matching..

23. Network Analysis Shortest path routines (line data) http://www.caliper.com/TransCAD/ApplicationModules.htm

24. Network Analysis.. Salesperson Problem (line data) http://www.caliper.com/TransCAD/ApplicationModules.htm

25. Network Analysis.. Location allocation (Line and polygon data) http://www.caliper.com/TransCAD/ApplicationModules.htm

26. Districting Delineation Political redistricting (polygon data)

27. Readings ► Chapter 3

28. http://ftp2.census.gov/geo/maps/special/HurKat/Katrina_Reference_v2.pdf

29. 4. TIGER

30. GBF/DIME Files.. http://www.geog.buffalo.edu/ncgia/gishist/DIME.html

31. http://ftp2.census.gov/geo/maps/special/HurKat/Katrina_Pop_Density_v2.pdf

32. http://ftp2.census.gov/geo/maps/special/HurKat/Katrina_Housing_Units_v2.pdf

33. http://ftp2.census.gov/geo/maps/special/HurKat/Katrina_Poverty_Rate_v2.pdf

34. http://ftp2.census.gov/geo/maps/special/HurKat/Katrina_Pop_Under_18_v2.pdf