A Finite-State Morphological Analyzer for Wolaytta

  • Tewodros A. GebreselassieEmail author
  • Jonathan N. Washington
  • Michael Gasser
  • Baye Yimam
Conference paper
Part of the Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering book series (LNICST, volume 244)


This paper presents the development of a free/open-source finite-state morphological transducer for Wolaytta, an Omotic language of Ethiopia, using the Helsinki Finite-State Transducer toolkit (HFST). Developing a full-fledged morphological analysis tool for an under-resourced language like Wolaytta is an important step towards developing further NLP (Natural Language Processing) applications. Morphological analyzers for highly inflectional languages are most efficiently developed using finite-state transducers. To develop the transducer, a lexicon of root words was obtained semi-automatically. The morphotactics of the language were implemented by hand in the lexc formalism, and morphophonological rules were implemented in the twol formalism. Evaluation of the transducer shows as it has decent coverage (over 80%) of forms in a large corpus and exhibits high precision (94.85%) and recall (94.11%) over a manually verified test set. To the best of our knowledge, this work is the first systematic and exhaustive implementation of the morphology of Wolaytta in a morphological transducer.


Wolaytta language Morphological analysis and generation HFST Apertium NLP 


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Copyright information

© ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2018

Authors and Affiliations

  • Tewodros A. Gebreselassie
    • 1
    Email author
  • Jonathan N. Washington
    • 2
  • Michael Gasser
    • 3
  • Baye Yimam
    • 1
  1. 1.Addis Ababa UniversityAddis AbabaEthiopia
  2. 2.Swarthmore CollegeSwarthmoreUSA
  3. 3.Indiana UniversityBloomingtonUSA

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