Stemming of French words based on grammatical categories

Automatic indexing systems use suffix stripping algorithms to cluster various words derived from a common root under the same stem. Currently, removing affixes to either a context-free or context-sensitive operation, where the context refers to the remaining stem. In this article, we propose a suffixing algorithm which uses grammatical categories to enhance the stemming process. This approach supports the use of foreign languages. In our case, the language is French, and a morphological analysis is required for removing inflectional suffixes or morphosyntactic variants of a lemma. After this analysis, we implement a suffix stripping algorithm which uses a dictionary and the grammatical categories to remove derivational suffixes. Our approach always returns a linguistically correct lemma, but not necessarily the “right” one. Based on our tests, this solution is an attractive one, with a mean error rate of 16%. We finish by explaining why we cannot expect significantly better results with this approach.