Analysis of GIS Data by Simple Examination - Introducing Geographic Information Systems with ArcGIS - page 388

4. If you don't find and download the files, examine the folder IGIS-Arc_AUX/DCD. There you will
find Extracted_Census_Files > output. In that folder note the existence of the above named
files. You will need these files in a later step if you were not able to (or inclined to) download
the files from the census bureau.
5. Before leaving the Census site, look at the population clocks again. (You might have to refresh
the Internet page so that the time changes: the F5 key usually works.) What time is it now?
________ What is the U.S. population? _______________. What is the world population?
_______________. How many people per hour are added to the U.S. population? ________.
How many people per hour are added to the world population? ________________. In 1950 the
world population was about two billion. Now it is about seven billion. We probably need to do
something about the dramatically increasing population—maybe using our GIS skills. Leave the
Census site.
Converting the Census Data Spreadsheet to
dBASEIV Format
6. Whether or not you were able to download the census data, you can do the conversion to
ArcGIS formats in the following steps. Use the computer's operating system to find the file
dt_dec_2000_sf1_u_data1.xls
in
[___] IGIS-Arc_AUX\DCD\Extracted_Census_Files\output
and copy it to
___IGIS-Arc_ YourInitials \Day_Care_Data
7. Still in the computer's operating system, pounce on the dt_dec_2000_sf1_u_data1.xls file. An
Excel spreadsheet should open. If not, start Microsoft Excel and go File > Open and choose
dt_dec_2000_sf1_u_data1.xls
Make the spreadsheet full screen. How many rows (expect thousands) are there in the
spreadsheet that contain population data?__ ________. That's how many census blocks there
are in the Knoxville CCD. (A CCD is a Census Collection District. In this case, it is a subset
of the Knoxville metropolitan area.) What are the five headings of the spreadsheet columns
(row 1)? ____________, ____________, ____________, ____________, ____________.
You are mainly interested in the GEO_ID and the P001001 columns. The Geography Identifier is (a part of)
the Block Number. The population column cells indicate the number of people living in the block.
8. Click the A1 cell, to make sure the spreadsheet is selected. Choose: File > Save As. Save it in
Day_Care_Data, but use the File name Census1.xls. Now Click Save As again, this time saving
with the File name Census2.