Melody learning and long-distance phonotactics in tone

摘要

This paper presents evidence that tone well-formedness patterns share a property of melody-locality, and shows how patterns with this property can be learned. Essentially, a melody-local pattern is one in which constraints over an autosegmental melody operate independently of constraints over the string of tone-bearing units. This includes a range of local tone patterns, long-distance tone-patterns, and their interactions. These results are obtained from the perspective of formal language theory and grammatical inference, which focus on the structural properties of patterns, but the implications extend to other learning frameworks. In particular, a melody-local learner can induce attested tone patterns that cannot be learned by the tier projection learners that have formed the basis of work on learning long-distance phonology. Thus, melody-local learning is a necessary property for learning tone. It is also shown how melody-local learners are more restrictive than learning directly over autosegmental representations.