Final Project

Cartography mapped us through a journey of 12 modules that led to this point. For the final project module, I created a bivariate map, where I displayed 2 thematic datasets over one geographic area. The topic of the map was to show the SAT mean composite scores in 2014 in each state coupled with the participation rate of each state. The importance of creating such maps is that it shows the empirical association between two variables. Presenting a map of the SAT scores in each state can be deceptive in how the data is perceived. Other variables can influence why one state has a higher performance than another state. The map that I produced will highlight how the participation rate of persons taking the SAT exam in each state relates to that state’s mean composite score.

To juxtapose the United States’ SAT 2014 mean composite scores next to each state’s participation rate, I chose to display the thematic datasets as a choropleth map for representation of the SAT mean composite scores and employed graduated symbols to signify the participation rate in each state. For the choropleth map depicting the  SAT mean composite scores, I chose a manual 5 class data classification with a graduated color scheme of blue. For the graduated symbols, I selected them over proportional symbols because they are classified data whereas proportional symbols are unclassified. Since the participation rate represented a percentage, I wanted to be able to break it down into classes that represented the data as evenly distributed as possible. Instead of employing 5 classes at Natural Breaks, I manually created 6 classes: 0%-10%, 11%-30%, 31%-50%, 51%-70%, 71-90%, and 91-100%. The intervals for 5 classes was much too large. For the map layout, I chose a landscape orientation because it is best suited for a map of the Unites States. I created 3 inset maps; an inset map each for Alaska and Hawaii so I could zoom on the mainland at an appropriate size without leaving Alaska and Hawaii off. For the third inset map, I zoomed in on an area of the east coast where the states are geographically small but they had the highest participation rate. I wanted the map reader to be able to see that while their test scores were lower than the national average, they also had the highest participation rate. I used Adobe Illustrator to isolate the graduated symbols and move them around each state to create the ideal visual hierarchy and balance. I chose a map projection of North America Albers Equal Area Conic because equal area projections are the ideal choice for thematic maps (Esri).

Every year, students across the country prepare for months for SAT Exams in the hopes of getting accepted into as prestigious a university as possible. If this map had only included the Mean SAT composite scores per state, people would have a skewed perception of what that data truly means. By employing a second dataset that showed the participation rate, the audience can get a better understanding about what those scores mean. The map does a good job depicting that while a cluster of states in the Midwest have the highest scores, they also have the lowest participation rate.