A rule-based approach of stemming for inflectional and derivational words in Bengali

Stemming is the process for reducing inflectional or derived words to its stem or root form. This paper presents an approach for finding out the stems from text in Bengali, which is highly inflectional in nature. In our process, we first stripped off the suffix part from Bengali words using some suffix stripping rules, depending upon the type of suffixes. Then we checked for the validity of the suffix stripped word as root word, using a Bengali dictionary. We have tested the process on Bengali collection of the FIRE 2010 data set with 50 queries using Lucene as the search engine and it gives a quite satisfactory result in terms of recall and MAP value.