Automatic Acquisition of a Slovak Lexicon from a Raw Corpus

Abstract

This paper presents an automatic methodology we used in an experiment to acquire a morphological lexicon for the Slovak language, and the lexicon we obtained. This methodology extends and refines approaches which have proven efficient, e.g., for the acquisition of French verbs or Croatian and Russian nouns, adjectives and verbs. It only relies on a raw corpus and on a morphological description of the language. The underlying idea is to build all possible lemmas that can explain all words found in the corpus, according to the morphological description, and to rank these hypothetical lemmas according to their likelihood given the corpus. Of course, hand-validation and iteration of the whole process is needed to achieve a high-quality lexicon, but the human involvement required is orders of magnitude lower than the cost of the fully manual development of such a resource. Moreover, this technique can be easily applied to other languages with a rich morphology that lack large-coverage lexical resources.

We would like to thank very warmly Katarína Mat’ašovičová, native speaker of Slovak, who has been our validator during the acquisition process described here.