Bivariate Chorograph

http://my.ilstu.edu/~jrcarter/Geo204/Choro/

This is an example of a bivariate chorograph because the map above focuses on two variables and has the same spacial pattern over an area. The two variables are the men and women ratios across the United States.  This map is also broken down into five groups with different ratios all labeled with different shades of green or white.