Enrichment of Inflection Dictionaries: Automatic Extraction of Semantic Labels from Encyclopedic Definitions

Abstract

Inflection dictionaries are widely used in many natural language processing tasks, especially for inflecting languages. However, they lack semantic information, which could increase the accuracy of such processing. This paper describes a method to extract semantic labels from encyclopedic entries. Adding such labels to an inflection dictionary could eliminate the need of using ontologies and similar complex semantic structures for many typical tasks. A semantic label is either a single word or a sequence of words that describes the meaning of a headword, hence it is similar to a semantic category. However, no taxonomy of such categories is known prior to the extraction. Encyclopedic articles consist of headwords and their definitions, so the definitions are used as sources for semantic labels. The described algorithm has been implemented for extracting data from the Polish Wikipedia. It is based on definition structure analysis, heuristic methods and word form recognition and processing with use of the Polish Inflection Dictionary. This paper contains a description of the method and test results as well as discussion on possible further development.