The Geography of Linguistic Diversity and the Provision of Public Goods

This paper analyzes the importance of local interaction between individuals of different linguistic groups for the provision of public goods at the national level. The micro-founded conceptual framework we develop predicts that a country's public goods (i) decrease in its overall linguistic fractionalization, and (ii) either increase or decrease in its local learning multiplier, a measure of how local interaction affects antagonism towards other groups in the society at large. After constructing a 5 km by 5 km dataset on language use for 223 countries, we empirically explore these theoretical predictions. While overall fractionalization worsens public goods outcomes, we find a positive causal effect of local learning. Conditional on a country's overall diversity, public goods outcomes are maximized when there are a few large-sized groups and the diversity of each location mirrors that of the country as a whole. Our large-scale study, spanning the entire globe, confirms experimental micro-evidence in favor of contact theory.