Culture, Contiguity and Conflict: On the Measurement of Ethnolinguistic Effects in Spatial Spillovers

Research on ethnolinguistic heterogeneity has so far mostly focused on domestic measures, while little attention has been paid to ethnolinguistic relations between nations. In this paper, I propose a way of measuring ethnolinguistic affinity between nations. This index measures the degree of similarity two randomly drawn individuals from two different populations are expected to display. I show that this measure has several attractive theoretical characteristics, which make it particularly useful. Subsequently, I construct the measure for all countries in Africa and use it to show that civil conflict in Africa is likely to spill over between contiguous ethnolinguistically similar countries.