This final project was
designed to utilize the cartographic skills, methods, and principles that were
learned throughout this course. To illustrate mastery of these
skills, a complex map depicting multiple layers of data was created. The
data used to create this map were the 2014 nationwide average SAT scores for
each state as well as each state’s student participation percentage in taking
the SAT. By mapping these two pieces of data together on the same
map, it could show a correlation between SAT scores and how many students
actually participated in the testing.
To create a map that
depicts two different sets of data, two thematic methods were chosen to provide
enough distinction between the data sets. The two thematic methods
used were choropleth mapping using graduated colors for the average composite
SAT scores in each state and proportional symbol mapping using graduated
symbols for the participation percentage.
The data for the state average SAT scores needed to
be combined into a composite score as it was provided as the three SAT section
scores. No normalization of the composite scores was applied to the
data. Once these scores were combined for each state, the resulting
composite scores were used to create a choropleth map of the United
States. Graduated color symbology was used in ArcMap to achieve
this. The data was also divided into five groups, or score ranges,
using the quantile breaks method. This was used to ensure an equal
number of states was in each group, providing some color differentiation and
even balance to the overall map. The color ramp for this data series
was red (lower SAT scores) to green (higher SAT scores
The
participation percentage data was taken directly from the source document and
no manipulation or normalization was required for mapping. To map
this data, proportional symbology, in the form of graduated circles, was used
to map the participation percentage on top of the existing choropleth map for
the average scores. A light blue circle with a black border was used
to contrast the color scheme of the base map. The actual percentage
was also placed inside the circle to clearly show the data on the
map. For this symbology the data was divided into five groups,
however using natural breaks instead of quantile.
As one looks at this map, you can quickly see that the
states with the higher average composite SAT scores also happen to be the
states reporting the lower participation percentage. One could
assume that only smarter students are encouraged to take the SAT’s in these
states where as the states with the lower averages and higher participation
rates have their average scores brought down by more average
students. One could also assume that if the states with lower
participation rates were to encourage more students to take the SAT, their
average composite scores would also come down and fall more in line with the
higher participating states.
So
this map brings this course to an end. I
will say that of all the GIS coursework I have done up till now, this has been
one of the more frustrating courses for me.
I think that is because a lot of the evaluation has been subjective in
interpretation. That combined with being
colorblind, application of certain principles has proven to be quite
challenging. This is definitely hasn’t been
as easy as just obtaining data and creating a map from it. That being said, I have learned a lot and I
guess the Marine in me gets enjoyment and fulfillment from challenging and
frustrating situations.