Bivariate Choropleth Map

http://go.owu.edu/~jbkrygie/krygier_html/geog_353/geog_353_lo/geog_353_lo07.html

A bivariate choropleth map is a choropleth map in which two different variables are displayed on the same map. By graphing them both on one map, viewers can analyze the relationship between the variables more easily than if they were on two separate documents. The map above shows, on the left, the population density, and on the right, the percentage of population change of a district in Russia. It is easier to examine the relationship between these variables of interest because they are on two maps of the same size right next to one another.