The objective of this
lab was to familiarize students with some techniques of data collection and
publishing maps in a professional format. I was tasked with downloading Census
data for the state of Wisconsin which I then manipulated so it would be
compatible with ArcGIS programs. I would then map this data and publish it to
an ESRI online service.
Objective 1: Downloading Census Data
For the first objective
of this lab I found information from the United States Census Bureau American
FactFinder website. The first dataset which I downloaded was the total
population of Wisconsin counties. The data set was located by entering
parameters within the advanced search function of the website. I ended up with
a zip file containing simple spreadsheets with the raw population data. None of
the data contained spatial representation. This led me to downloading the
Wisconsin counties shapefile from the FactFinder website.
Objective 2: Joining data sets
Once both the data sets
which I had downloaded were imported into the ESRI ArcMap program I had to
combine them using the “join” feature from ArcMap. I was able to use GEO_ID, an
attribute shared by both tables, as the key field for my join. After completing
the operation the attribute table of the county shapefile included the
population data from the other downloaded file. But when attempting to
symbolize the population data I found out that I had to further manipulate the
data. The state population was a sting field type (typically used to map
nominal data). To map quantities on ArcMap the data type must be set as a
quantitative data type. I was able to add an attribute field containing the
same information as the original but with a double field. This is much better
suited to expressing numbers and ArcMap recognizes that the data can be mapped
quantitatively. Below I have included an image of the symbolized population
data and the joined attribute table (Figure 1).
Figure 1. Symbolized
population data with labeled attribute table types, note the identical
numerical data in the original and new fields.
Objective 3: Displaying Housing Data
The third objective for
this lab was quite similar to the previous parts of this lab. I downloaded
another data set, total Housing in Wisconsin Counties, from the FactFinder
website. I joined the information with the Wisconsin shapefile attribute table
using the same processes and operations as earlier. The only difference being
that I defined the new attribute file data type as long integer instead of
double field type. I will concede that this field type requires more memory
than double floating but I wanted to see how ArcMap would interact with this
slight difference in how a field is defined. I noticed no change in how the
data were symbolized.
Objective 4: Build a Layout
My next objective is to
make a cartographically sound layout for them. I designed a landscape document
with two data frames, each of which displayed a map of Wisconsin. I set the
scale of both data frames to 1:4,550,000 and used a Nad 1983 HARN projection
designed for Wisconsin (WKID: 3071). I added basic cartographic elements such
as scale bars, north arrows, and a legend for both data frames. I choose not to
include a base map of any type because I feel that it would overcomplicate a
map of this scale where spatial relationships are not pertinent to precise
location. I have attached the completed map below (Figure 2).
Objective 5: Publishing to ArcGIS Online
For this objective I
was tasked to publishing the map document I created to ArcMap online and
editing the data display using the services which ESRI offers on their website.
After filling out a basic summary for the map I had to remove both table joins
to publish the map. Seeing as I had already made new fields and transferred the
data to them this was not a problem for the display of data. From this point
publishing the data was not a problem.
The final step of this
lab was to share my completed webmap to the UWEC Geography and Anthropology
organization (One needs to be in this group to see this map). Here is the web link to view the map: http://uwec.maps.arcgis.com/home/webmap/viewer.html?webmap=88b46650ec2b49fa89045e2f402efc8e.
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