Proportional Symbol Map

The purpose of this activity was to introduce manual proportional symbol mapping with Microsoft Excel and Adobe Illustrator CS5.

Requirements 

- The map must contain at least 30 geographic units (countries, counties, cities, etc.)

 Data was collected from the U.S Census Bureau and then sorted from highest to lowest values.   By using the largest percentage value as the largest proportional symbol, I was then able to appropriately size the other percentages as fractions of the largest circle.  The major struggle of this assignment was manually sizing the symbols in Illustrator.  This was an easy task, but rather time consuming.  I chose to map poverty data in Wisconsin because I feel that it often gets overlooked.  People often believe that the majority of poverty exists only in third world countries or large cities, but this map shows that Poverty exists everywhere no matter where you live.   I chose to use percentages as my data because I feel gives a better visual representation of the data.  Counties such as Milwaukee County that have large populations sizes are naturally going to have larger numbers of people in poverty.  That value is meaningless unless you are able to compare that number to the total population size.


Discussion:  This map provides excellent visual hierarchy, clarity, legibility, and figure ground.  The only draw back would be that the use of percents instead of actual number of people resulted in a smaller range of circle sizes.  This results in a slight reduction in clarity, yet still reasonable.