Measuring ethno-linguistic affinity between nations

Research on ethno-linguistic ties has so far mostly focused on domestic measures of ethno-linguistic heterogeneity. Little attention has been given to the possibility that ethno-linguistic relations between countries may affect out- comes, particularly in a spatial econometric context. In this paper, I propose a way of measuring Ethno-Linguistic Affinity between nations. This new index measures the degree of similarity two randomly drawn individuals from two different populations can be expected to display. I show that this measure has a number of attractive theoretical characteristics, which make it particularly useful and continue to actually construct such a measure for all countries in Africa. Finally, using this measure of Ethno-Linguistic Affinity, I show that civil conflict in Africa is likely to spill over between contiguous ethno-linguistically similar countries.