Minority language and the stability of bilingual equilibria

Abstract

We investigate a society with two official languages: A, shared by all individuals, and B, spoken by a bilingual minority. A model is developed in which the bilingual agents must make strategic decisions about the language to be used in a conversation. The decisions are taken under imperfect information about the linguistic type of the participants. We show that the bilingual population is optimally partitioned into two groups, one composed of agents who strategically hide their bilingual nature and the other composed of those who reveal it. As a consequence, in the interactions between members of the former group the language used is A, having therefore coordination failures on the minority language. We show that this mixed strategy Nash equilibrium has strong stability properties: it is evolutionarily stable and, dynamically, asymptotically stable for the one-population replicator dynamics. These properties might explain the difficulties encountered by language policies directed at promoting the use of minority languages.JEL Classification Numbers: C72, D81.