Extracting Sense Trees from the Romanian Thesaurus by Sense Segmentation & Dependency Parsing

Abstract: This paper aims to introduce a new parsing strategy for large dictionary (thesauri) parsing, called Dictionary Sense Segmentation & Dependency (DSSD), devoted to obtain the sense tree, i.e. the hierarchy of the defined meanings, for a dictionary entry. The real novelty of the proposed approach is that, contrary to dictionary 'standard' parsing, DSSD looks for and succeeds to separate the two essential processes within a dictionary entry parsing: sense tree construction and sense definition parsing. The key tools to accomplish the task of (autonomous) sense tree building consist in defining the dictionary sense marker classes, establishing a tree-like hierarchy of these classes, and using a proper searching procedure of sense markers within the DSSD parsing algorithm. A similar but more general approach, using the same techniques and data structures for (Romanian) free text parsing is SCD (Segmentation-Cohesion-Dependency) (Curteanu; 1988, 2006), which DSSD is inspired from. A DSSD-based parser is implemented in Java, building currently 91% correct sense trees from DTLR (Dictionarul Tezaur al Limbii Române -- Romanian Language Thesaurus) entries, with significant resources to improve and enlarge the DTLR lexical semantics analysis.