Morphological Analyzer for Affix Stacking Languages: A Case Study of Marathi

In this paper we describe and evaluate a Finite State Machine (FSM) based Morphological Analyzer (MA) for Marathi, a highly inflectional language with agglutinative suffixes. Marathi belongs to the Indo-European family and is considerably influenced by Dravidian languages. Adroit handling of participial constructions and other derived forms (Krudantas and Taddhitas) in addition to inflected forms is crucial to NLP and MT of Marathi. We first describe Marathi morphological phenomena, detailing the complexities of inflectional and derivational morphology, and then go into the construction and working of the MA. The MA produces the root word and the features. A thorough evaluation against gold standard data establishes the efficacy of this MA. To the best of our knowledge, this work is the first of its kind on a systematic and exhaustive study of the Morphotactics of a suffix-stacking language, leading to high quality morph analyzer. The system forms part of a Marathi-Hindi transfer based machine translation system. The methodology delineated in the paper can be replicated for other languages showing similar suffix stacking behaviour as Marathi.