March 13 th , 2007 by Indraneel Kumar, AICP; Spatial and GIS Analyst

1. Commuting Patterns in Indiana: A GIS Approach March 13th, 2007 by Indraneel Kumar, AICP; Spatial and GIS Analyst Christine Nolan, Senior Associate Purdue Center for Regional Development Purdue University Acknowledgements: Eda Unal, Graduate Research Assistant, Purdue Center for Regional Development, Purdue University

2. What is Commuting? • Movement / travel for a “trip” purpose • Work purpose- “Place of Work” and “Place of Residence” • Trip purpose could be shopping, school, recreational, social, etc. • Each trip has an “origin” and “destination” • A trip could be “unlinked” or “linked”

3. Parameters • Purpose • Travel time- peak/non-peak • Travel mode • Drove alone vs. • car/van pooling Source: FHWA, FTA, DOT

4. At a Glance • Nationally, average travel time for commuting to job (workers 16 years and over) was 26 minutes in 2000 • In 1990, 22 minutes • About 76 % workers (who did not work at home) drove alone in 2000 • In 1990, 73% Source: U.S. Census Bureau, Decennial Census

5. At a Glance • Based on American Community Survey • In 2005, average travel time for commuting to job is 25.1 minutes • About 77% workers (who did not work at home) drove alone to work • Nationwide Personal Transportation Survey (NPTS), 1995 Source: U.S. Census Bureau, Bureau of Transportation Statistics

6. Data Characteristics • Census Transportation Planning Package, 2000 • Available from Federal Highway Administration, U.S. DOT • Bureau of Transportation Statistics, Transtats • Based on Census 2000 Long Form Questionnaire • 1 in 6 households in the U.S. covered by the survey • Various data products- Place of Residence, Place of Work, Journey to Work Flow Tables • County-County Worker Flows

7. County-County Worker Flows • Place of Residence and Place of Work Counties • Commuter Flow methodology by FHWA • Available at http://www.fhwa.dot.gov/ctpp • Data available at http://www.census.gov/population/www/cen2000/commuting.html • Select the whole State (Indiana) • ---- Residence County ---- Work County

8. Simple Mapping of Net- Commuting

9. County-County Worker Flows • Converting the Excel file into “line feature class” • - Convert County Boundary into Center-Point feature class • Excel into DBF IV • Join center-point table to DBF to populate coordinates • Join Indiana counties as residence and then as workplace • Each pair of Indiana counties has two entries • Convert the DBF IV into “flow line” • Query and refine Tools Used: ET Geo Wizards, ArcGIS Toolbox

10. Process

11. Process

12. Process

13. Join by using Res_StCo (Residence State and counties) to populate the Indiana counties • If Indiana counties are residence- they are populated (2,555 out of 5,239 records in total) • Fill in X and Y Coordinates • Export as Indiana Residence Counties (DBF) file • Join by using Wrk_StCo (Work State and counties) to populate the Indiana counties • All work counties are Indiana counties- each record is populated (5,239 records in total) • Fill in X and Y Coordinates • Export as Indiana Work Counties (DBF) file Process

14. Add Indiana Residence Counties (DBF) and Indiana Work Counties (DBF) as Event Themes • County center points outside of Indiana will come the origin (0,0) • Put Spatial Reference- projection system Process Origin (0,0)

15. Merge the Two Event Themes by using “Merge Function” in ArcGIS Toolbox • Since “fields names” for both the themes are constant, this results into 10,478 records or two tables are merged into one “feature class” • Each unique id. (Residence State-Residence County-Work State- Work County) will be repeated twice, only X and Y coordinates will change • If Residence and Work Counties are same- X and Y coordinates remain the same • ET Geo Wizards “Point to Polyline” • A flow-line is created between each Residence-Work County pairs (5,239 lines) • Commuters coming from Residence County outside of state receives origin (0,0) coordinate as one end • Populate commuter count data by joining the tables Process

16. Within County and County to County Journey to Work (JTW) Process

17. Commuting Patterns

18. Interstates

19. State Highways

20. Inferences • Generally, small dots represent bedroom communities and large dots are major employment centers (Marion County) • Flow direction is from small dots to large dots • Reverse flow is small and hidden beneath the larger flow • small dots connected to other small dots represent rural regions • Forms of major metropolitan areas emerge by using the Flow Maps

21. Counties • Queries at a county level is possible

22. Commuting to-from neighboring states

23. Metropolitan Areas

24. Lake County as Residence-origin • Lake County as Work-destination

25. Further Explorations? • Integrate other transportation variables • Means of Transportation • Travel Time • Lower Geographies- Traffic Analysis Zones (TAZs) • Interactive GIS Database • Other Methods of Flow Mapping • Movement of Goods • Exploring Tobler’s Flow Mapper

26. Further Explorations? • Tobler’s Flow Mapper • Center for Spatially Integrated Social Science (CSISS), University of California, Santa Barbara • Movement Mapping- Migration, Flow of $, Journal Citations Source: Prof. Waldo Tobler

27. Thank you! Indraneel Kumar Purdue Center for Regional Development Purdue University 1201 W. State Street West Lafayette, IN 47907-2057 Office: 765-494-PCRD (7273) Toll Free: 877-882-PCRD (7273) Fax: 765-494-9870 email: PCRDinfo@purdue.edu Tel: 765-494-9485 email: ikumar@purdue.edu