GINI: the Inequality index

Gini index measures the extent to which the distribution of income (or, in some cases, consumption expenditure) among individuals or households within an economy deviates from a perfectly equal distribution.

http://data.worldbank.org/indicator/SI.POV.GINI?order=wbapi_data_value_2012+wbapi_data_value&sort=asc

Yale's mathematical model for selfishness.

The study suggests that:

"Cross-culturally, it suggests that those who grow up in countries without a strong rule of law will develop an uncooperative intuition, he adds"

Ring a bell?

http://qz.com/601634/yale-psychologists-have-built-a-mathematical-model-for-selfishness/