Module 6: Data Classification

In this module we learned about four common data classification methods: Equal Interval, Quantile, Natural Breaks, and Standard Deviation. For our lab assignment we were instructed to create a map depicting the percentage of the population above 65 in Escambia county using each of the four data classification methods mentioned. My map is comprised of four data frames, top left is the Natural Breaks classification method, top right is the Quantile classification method, bottom left is the Equal Interval classification method, and bottom right is the Standard Deviation classification method. Each frame has its own legend displaying the class ranges, this is necessary since each classification method organizes its classes differently. Also essential map elements were added, such as the title, north arrow, and scale bar.

I created this map using ArcMap following the lab protocol. The shapefile of Escambia county that was used contained a plethora of information collected by the 2010 US Census Bureau. In order to label the census tracts with the information I wanted (percentage of pop. above 65) I had to search among the many fields under the (Label Properties>Symbology>Quantities>Graduated Colors) 'value' drop-down list. My next step was to determine an appropriate color ramp, used to represent each class. I usually have difficulty when it comes time to choose a color scheme.  For three of the data frames I chose a color ramp with increasing gradient to depict a change from low values (light colors) to high values (dark colors) but took time finding one that had strong contrast between colors in order to easily differentiate each class. For the Standard Deviation frame an increasing gradient color ramp is not appropriate since all of the data focuses on a center point, for this method a divergent color ramp is best. After making sure all the data frames were assigned to a new classification method and had accurate information it was time to switch over to layout view and start making my document look like a map! Layout view shows the full extent of your page and is used to organize and balance your data frames and all essential map elements. Only in layout view are you allowed the option to create a legend under the 'Insert' tab. In layout view I finalized my map by adding all legends, titles, and essential map elements. Most of my time spent on this lab was spent attempting to achieve balance in my map. A quick Google search led me to the ArcGIS resources page which provided me with a lot of useful information on how to align objects and organize data frames. The ruler and grid lines were also very helpful during the alignment process.