Robust Language Acquisition - an Emergent Consequence of Language as a Complex Adaptive System

Each of us as learners had different language experiences, yet we have converged on broadly the same language system. From diverse, noisy samples, we end up with similar competence. How so? Some views hold that there are constraints in the learner’s estimation of how language works, as expectations of linguistic universals pre-programmed in some innate language acquisition device. Others hold that the constraints are in the dynamics of language itself – that language form, language meaning, and language usage come together to promote robust induction by means of statistical learning over limited samples. The research described here explores this question with regard English verbs, their grammatical form, semantics, and patterns of usage. Analyses of a 100-million-word corpus show how Zipfian scale-free distributions of usage ensure robust learning of linguistic constructions as categories: constructions are (1) Zipfian in their type-token distributions in usage, (2) selective in their verb form occupancy, and (3) coherent in their semantics. Parallel psycholinguistic experiments demonstrate the psychological reality of these constructions in language users.