Information-theoretic applications to Hupa verbal morphology

Abstract

Hupa (Na:tinixwe Mixine:whe’) is a Pacific Coast Dene language spoken in Hoopa Valley in Northern California. Like its Dene sisters, Hupa exhibits complex verbal morphology which has attracted decades of theoretical research. One approach that has yet to have been applied to these languages is information theory. Previous information-theoretic research into verbal morphology has uncovered a cross-linguistic trend of grouping predictive information closer together and finding morphemes that are more mutually-informative to the root closer to the root, which in turn reduces overall surprisal and is easier on memory constraints. However, these studies analyzed prominently suffixing languages of Afro-Eurasia. This project is the first application of these information-theoretic concepts to a Dene language to investigate if these approaches also apply to explain morpheme order in a low-resource, Indigenous American language with intricate, prominently-prefixing morphology. The results indicate similar findings to previous research. Hupa demonstrates a word-level linear morpheme order that, on average, orders most mutually-informative morphemes closest to the verb root compared to a randomized baseline. This morpheme order also resulted in an average surprisal that was more comparable to optimized morpheme orders than a randomized baseline. Morpheme-type mutual information, however, demonstrates the discrepancies between word- and templatic-level information content in Hupa, which exemplifies the word-level efficiency that Hupa shares with other languages despite the typological uniqueness of its morphological grammar.