Choropleth Mapping

• ColorBrewer – Website for selecting choropleth color ramps by noted cartographer Cynthia Brewer.
• Color Scheme Types and Combinations – These graphics from an early paper by Brewer laid the groundwork for ColorBrewer. Although bivariate color schemes are not represented in the ColorBrewer palettes, this shows some of her forays in that direction.
• Bivariate Choropleth Maps: A How-to Guide