Search (1 results, page 1 of 1)

  • × author_ss:"Batet, M."
  • × theme_ss:"Wissensrepräsentation"
  1. Sánchez, D.; Batet, M.; Valls, A.; Gibert, K.: Ontology-driven web-based semantic similarity (2010) 0.02
    0.022275863 = product of:
      0.044551726 = sum of:
        0.044551726 = product of:
          0.08910345 = sum of:
            0.08910345 = weight(_text_:mining in 335) [ClassicSimilarity], result of:
              0.08910345 = score(doc=335,freq=2.0), product of:
                0.28585905 = queryWeight, product of:
                  5.642448 = idf(docFreq=425, maxDocs=44218)
                  0.05066224 = queryNorm
                0.31170416 = fieldWeight in 335, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  5.642448 = idf(docFreq=425, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=335)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    Estimation of the degree of semantic similarity/distance between concepts is a very common problem in research areas such as natural language processing, knowledge acquisition, information retrieval or data mining. In the past, many similarity measures have been proposed, exploiting explicit knowledge-such as the structure of a taxonomy-or implicit knowledge-such as information distribution. In the former case, taxonomies and/or ontologies are used to introduce additional semantics; in the latter case, frequencies of term appearances in a corpus are considered. Classical measures based on those premises suffer from some problems: in the ?rst case, their excessive dependency of the taxonomical/ontological structure; in the second case, the lack of semantics of a pure statistical analysis of occurrences and/or the ambiguity of estimating concept statistical distribution from term appearances. Measures based on Information Content (IC) of taxonomical concepts combine both approaches. However, they heavily depend on a properly pre-tagged and disambiguated corpus according to the ontological entities in order to computer accurate concept appearance probabilities. This limits the applicability of those measures to other ontologies - like specific domain ontologies - and massive corpus - like the Web. In this paper, several of the presente issues are analyzed. Modifications of classical similarity measures are also proposed. They are based on a contextualized and scalable version of IC computation in the Web by exploiting taxonomical knowledge. The goal is to avoid the measures' dependency on the corpus pre-processing to achieve reliable results and minimize language ambiguity. Our proposals are able to outperform classical approaches when using the Web for estimating concept probabilities.