Visualizing Hierarchies - Spatial Mathematics: Theory and Practice through Mapping - page 167

features, the median age, and other factors. How do you think the diversity
index in San Diego County or in your county has changed over time? Name
some reasons why it changes. The diversity index, like other variables we are
examining, changes constantly because of the reasons mentioned above that
are economic and social in nature, local in scale but also affected by national
and international forces.
You have just used ArcGIS Online along with ArcGIS for Desktop to create
some quick maps based on Census data in the context of examining spatial
patterns and analysis in order to investigate pattern of diversity in California
and other places of interest to you. Investigate the other data sets in ArcGIS
Online ( http://www.esri.com/arcgisonline ) including imagery, topography,
political boundaries, land cover, and much more for your data and project
needs.
7.4.3 Denver Internet café analysis
In Chapter 3, you created a map using a GIS called “InternetCafeSites” or
some similar name using Census data as you sought to determine the ideal
location for an Internet café in Denver. The activity below will build on the
map you made. It will guide you through the use of Census data to create
classified choropleth maps, the creation of a dot density map (foreshadowed
in Chapter 5), and elements involving the normalization of data (foreshad-
owed in Chapter 6). A link to the full study is provided below. Again, look
for where the concept of nested hierarchy enters the picture.
In Chapter 3, we found regions within one kilometer of a high school, univer-
sity, or college, which was one of the criteria deemed advantageous to consider
for the location of the Internet café. Here we will solve another component:
In what Denver neighborhoods is the percentage of 18 to 21 year-olds greater
than 10% of the total population of those neighborhoods? This demographic
characteristic is also deemed useful for the café's location. These neighbor-
hoods tend to be near universities, such as in northwest Denver, in down-
town Denver, and in south central Denver, the sites of Regis University, the
University of Colorado at Denver, and the University of Denver, respectively.
Open the table for the Block Groups polygons for Denver City and County.
How many records exist in this table; that is, how many block groups exist
in Denver City and County? There are 470 block groups in Denver City and
County. What geographic extent do you think the longer table of Census
variables covers? The longer table, the one with 3278 records, is all of the
block groups for the state of Colorado. What is the name of the common
field that these two tables share? The common field is named STFID, or
“state federal ID.”
Notice that your map file (shp file) contains block groups but no Census data.
Your data table contains Census data but no map. In the next step, you will
join the data table to the map. Clear any selected records in both tables so