SIEMÊS – A Named-Entity Recognizer for Portuguese Relying on Similarity Rules

  • Luís Sarmento
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3960)


In this paper we describe SIEMÊS, a named-entity recognition system for Portuguese that relies on a set of similarity rules to base the classification procedure. These rules try to obtain soft matches between candidate entities found in text and instances contained in a wide-scope gazetteer, and avoid the need for coding large sets of rules by exploiting lexical similarities. Using this matching procedure, SIEMÊS generates a set of classification hypotheses based solely on internal evidence, which may be disambiguated in a later step by relatively simple rules based on contextual clues. We explain SIEMÊS architecture and its named-entity identification and classification procedure. We also briefly discuss the results of the participation of SIEMÊS in HAREM, the named-entity evaluation contest for Portuguese, and describe future work.


Machine Translation Semantic Role Similarity Rule Name Entity Recognition Entity Recognition 
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 2006

Authors and Affiliations

  • Luís Sarmento
    • 1
  1. 1.Faculdade de Engenharia Universidade Porto (NIAD&R) & Linguateca (Porto Node)Portugal

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