IndiLem@FIRE-MET-2014 : An Unsupervised Lemmatizer for Indian Languages

An unsupervised and language independent lemmatization procedure has been developed for major Indian languages (Bengali, Hindi etc) which are morphologically very rich and agglutinative in nature. The task of a lemmatizer is mapping an inflected surface word to its appropriate dictionary root word and it is a pre-requisite for implementing several NLP tools like Word Sense Disambiguation system, Machine Translation system, etc. Here the proposed method builts a trie structure using the root words from dictionary and tries to find out a potential lemma of a surface word by efficiently searching in the trie. In this present work, our lemmatization system is tested on Bengali.