We present a theory of ethnic conflict in which coalitions formed along ethnic lines compete for the economy%u2019s resources. The role of ethnicity is to enforce coalition membership: in ethnically homogeneous societies members of the losing coalition can defect to the winners at low cost, and...

We define a country's technology as a triple of efficiencies: one for unskilled labor, one for skilled labor, and one for capital. We find a negative cross-country correlation between the efficiency of unskilled labor and the efficiencies of skilled labor and capital. We interpret this finding...