This study documents the analogical changes in the speech of four Alamblak men over a period from twenty-five to thirty-eight years. The data reveal many changes that were not apparently phonologically predictable by several phonological hypotheses that have been proposed in the literature on paradigm leveling. Many changes made by the subjects of the study were reversed by themselves over the time period of the study. The reversals of earlier changes suggest that change is influenced by existing paradigms and the autonomy and automatization of allomorphs in certain lexical contexts. The idiosyncratic nature of other changes suggests that they were not entirely determined by those processes of language use, but that speaker-initiated grammar replacement had occurred, perhaps motivated by a goal of paradigmatic uniformity.
The study points out that young speakers were faced with a surface complexity of alternating morphemes due to a highly abstract phonological system underlying the adult speech in 1970.