A choropleth map compares values across geographic regions by varying each region’s color. A sequential color scale maps a continuous statistic to a continuous range of colors. section 13.2.3
A practical D3 implementation combines:
- A d3.scaleSequential scale using d3.interpolateYlGnBu, with a domain capped at 100 so smaller differences remain readable. section 13.2.3
Nobel laureates by country
Map each country’s number of Nobel laureates from yellow for low values through turquoise to dark blue for high values, while leaving countries with none nearly white.
