The greener countries are more ethnically diverse and the orange countries more homogenous. There are a few trends you can see right away: countries in Europe and Northeast Asia tend to be the most homogenous, sub-Saharan African nations the most diverse. The Americas are generally somewhere in the middle. And richer countries appear more likely to be homogenous.
This map is particularly interesting viewed alongside data we examined yesterday on racial tolerance, as measured by the frequency with which people in certain countries said they would not want a neighbor from a different racial group.
When five economists and social scientists set out to measure ethnic diversity for a landmark 2002 paper for the Harvard Institute of Economic Research, they started by comparing data from an array of different sources: national censuses, Encyclopedia Brittanica, the CIA, Minority Rights Group International and a 1998 study called “Ethnic Groups Worldwide.” They looked for consistence and inconsistence in the reports to determine what data set would be most reliable and complete. Because data sources such as censuses or surveys are self-reported – in other words, people are classified how they ask to be classified – the ethnic group data reflects how people see themselves, not how they’re categorized by outsiders. Those results measured 650 ethnic groups in 190 countries.