We present a theory of ethnic conflict in which coalitions formed along ethnic lines competefor the economy’s resources. The role of ethnicity is to enforce coalition membership: inethnically homogeneous societies members of the losing coalition can defect to the winnersat low cost, and this...

We study cross-country differences in the aggregate production function whenskilled and unskilled labor are imperfect substitutes. We find that there is a skill biasin cross-country technology differences. Higher-income countries use skilled labormore efficiently than lower-income countries,...

In this paper we apply the same framework totime-series data from the United States over theperiod 1963–1992. We find that throughout thisperiod the efficiencies of skilled labor and capitalhave risen. The efficiency of unskilled laborhas risen in tandem with those of the otherfactors in the...