Structure Sensitive Tier Projection: Applications and Formal Properties

  • Aniello De SantoEmail author
  • Thomas Graf
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11668)


The subregular approach has revealed that the phonological surface patterns found in natural language are much simpler than previously assumed. Most patterns belong to the subregular class of tier-based strictly local languages (TSL), which characterizes them as the combination of a strictly local dependency with a tier-projection mechanism that masks out irrelevant segments. Some non-TSL patterns have been pointed out in the literature, though. We show that these outliers can be captured by rendering the tier projection mechanism sensitive to the surrounding structure. We focus on a specific instance of these structure-sensitive TSL languages: input-local TSL (ITSL), in which the tier projection may distinguish between identical segments that occur in different local contexts in the input string. This generalization of TSL establishes a tight link between tier-based language classes and ISL transductions, and is motivated by several natural language phenomena.


Subregular hypothesis TSL Phonotactics Input strictly local functions Generative capacity 



This material is based upon work supported by the National Science Foundation under Grant No. BCS-1845344.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of LinguisticsStony Brook UniversityStony BrookUSA

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