Final Project -Rise of the budding cartographer

The focus of this project was to create a publishing quality map illustrating the relationship between 2014 Composite Mean SAT Scores and the test participation rates by graduating seniors within the conterminous United States and the non-contiguous states of Alaska and Hawaii.  The map is intended to accompany an article in the Washington Post discussing high school seniors and college entrance scores.

In order to best present the bivariate data, I chose to create a choropleth map with graduated, range-graded symbols.   A choropleth map is ideal for displaying uniformly distributed data within each enumeration unit where change occurs at the enumeration unit boundaries.  The composite SAT scores are shown by applying a color gradient scheme to the States.    I chose to class the composite mean test score values using a defined interval of 100 with six classes.  While this reasonably represented the data, I wanted to better convey the high end outliers.  By tweaking the last break point to cover the range between 1,800 and 1,816 I was able to represent the data more accurately.  I selected a suitable six class color scheme using color brewer. (Brewer, 2002-13)  Superimposed on each state is a graduated, range-graded symbol illustrating the graduating senior test participation rate.  The 2014 participation rates were classed using Natural Breaks (Jenks) with seven classes.  I chose to show the class ranges using the feature values to accurately depict the percentages even though this showed percentage gaps in the legend; the reason for the gaps was explained within the map subtext.  While the other classification options (Equal Interval, Defined Interval, Quantile, Geometrical Interval and Standard Deviation) provided reasonably similar results I chose to use Natural Breaks (Jenks) because this method minimizes the difference between values in the same class and maximizes the difference between classes.  Once I had properly classified the data I shifted my focus to developing my layout and design.  The conterminous states served as the primary map; I included insets for Alaska and Hawaii since the page size restricted their visibility within the primary map.  For clarity, I created an inset map of the Northeastern United States so that the State names and graduated symbols could be easily distinguished.  I added all required map elements, but kept stylization to a minimum within ArcDesktop.  Finishing effects were created using Adobe Illustrator with attention to Gestalt principles.  The Gestalt theory, developed in the 1920s, describes how humans recognize individual components in a graphic image and organize them into a unified whole.  The Northeastern inset map applies closure which is our ability to complete an image even with parts missing; in this instance we visually interpret the dashed line to represent the square in its entirety, without gaps.  In order to apply figure-ground, I made the primary map elements a lighter color than the background.  I also applied stylization effects including feathering and drop shadow so that the objects appeared to be visually closer to the reader.  I feel the feathering effect helped to emphasize the importance of these items and direct the reader’s attention to them.  By making the graduated symbols darker than the states, I was able to apply visual hierarchy so that the symbology was emphasized without detracting or obscuring the underlying states.  While all of the previously discussed items are important to an accurate map and good cartographic design they are all for naught if an incorrect projection is used.  Because we were comparing data by area it was important to choose a projection which preserved area.  There are four main equal area projections:  Globe, Sinusoidal Equal Area, Lambert Azimuthal Equal Area and Albers Equal Area Conic.  By looking at the size and directionality of my subject matter these choices could be further narrowed to those suiting small regions or countries resulting in either Lambert Azimuthal Equal Area or Albers Equal Area Conic.  Narrowing by extent, I selected the Albers Equal Area Conic which is suited for large, mainly east/west areas of mid-latitude.  Additionally, this projection is a good choice for thematic and presentation maps.  ArcDesktop offers further refinement to this projection by setting the longitudinal center to -96, the first standard parallel to 20, the second standard parallel to 60 and the latitudinal center to 40.  I chose this projection, designated as North America Albers Equal Area Conic for my project.  

This project allowed me to utilize the cartographic methods, techniques and skills I had acquired during the semester.  The importance of visualizing the data distribution, defining the map purpose and audience became clear when attempting to design a map with no detailed instructions.  While daunting at first, the task quickly became enjoyable as I was able to recall and apply what I had learned throughout this course.  Because of the experience gained this semester, I was able to create the ArcDesktop portion of the map with relative ease.  Although I had not used Adobe Illustrator in the more recent labs, I was pleased to note that I was able to recall and apply the skills I had learned.  As I was less intimidated by the software, I was able to explore new options and find better ways to manipulate the objects that I had imported from ArcDesktop.  Comparing the .mxd file to the .ai file leaves no doubt that using Adobe Illustrator greatly improves the maps presentation value.  Not only did this project make me an acolyte of Adobe Illustrator, it also strengthened my confidence in the skills learned throughout this semester.  I am more enthusiastic about the remaining coursework and the possibilities that GIS brings to my future.