Gini coefficient map
Posted at 11 p.m., Oct. 21, 2011

The map as a whole, including the legend and the quiz.
The map as a whole, including the legend and the quiz.
Users can toggle each decile individually, allowing comparisons such as this one, which looks at the two extremes.
The quiz asks users to guess which of two countries has an income distribution most like a third country.
Selecting a country shows the other countries in its decile.
One of the NewsHour's long-term economics reporting projects has been on income inequality — both domestically and internationally. One of our approaches to this topic involved using the Gini coefficient, an index of income inequality in a population, to compare the income distributions of various countries, including the United States.
This measure has been used before (such as in a recent Information is Beautiful post), but we wanted to give people two ways to view and interpret this data: a choropleth map grouping the different countries into deciles and a simple quiz that asked users about which countries they believed to have more equal income distributions to each other.