A number of Russian verbs lack 1sg nonpast forms. These paradigmatic gaps are puzzling because they seemingly contradict the highly productive nature of inflectional systems. We model the persistence and spread of Russian gaps via a multi-agent model with Bayesian learning. We ran three simulations: no grammar learning, learning with arbitrary analogical pressure, and morphophonologically conditioned learning. We compare the results to the attested historical development of the gaps. Contradicting previous accounts, we propose that the persistence of gaps can be explained in the absence of synchronic competition between forms.
Robert Daland, Andrea D. Sims, Janet Pierrehumbert