Automatic Extraction of Definitions in Portuguese: A Rule-Based Approach

  • Rosa Del Gaudio
  • António Branco
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4874)


In this paper we present a rule-based system for automatic extraction of definitions from Portuguese texts. As input, this system takes text that is previously annotated with morpho-syntactic information, namely on POS and inflection features. It handles three types of definitions, whose connector between definiendum and definiens is the so-called copula verb “to be”, a verb other that one, or punctuation marks. The primary goal of this system is to act as a tool for supporting glossary construction in e-learning management systems. It was tested using a collection of texts that can be taken as learning objects, in three different domains: information society, computer science for non experts, and e-learning. For each one of these domains and for each type of definition typology, evaluation results are presented. On average, we obtain 14% for precision, 86% for recall and 0.33 for F 2 score.


Information Society Automatic Extraction Prepositional Phrase Punctuation Mark Test Corpus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Rosa Del Gaudio
    • 1
  • António Branco
    • 1
  1. 1.University of Lisbon, Faculdade de Ciências, Departamento de Informática, NLX - Natural Language and Speech Group, Campo Grande, 1749-016 LisbonPortugal

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