Range Graded Proportional Circle Map

Range Graded Proportional Circle Maps use shaded circles to represent a numerical range of the data being measured. The data being measured is separated into groups based breaks or quantiles and the cartographer will use a number of methods such as shading or circle size to represent different ranges. The map below uses both techniques to show the Indian population of the western United States.




http://www.neiu.edu/~smkope/387/BasicPage/Proportional%20Circle%20Map.jpg