• NP animacy identification for anaphora resolution

      Orasan, Constantin; Evans, Richard (American Association for Artificial Intelligence, 2007)
      In anaphora resolution for English, animacy identification can play an integral role in the application of agreement restrictions between pronouns and candidates, and as a result, can improve the accuracy of anaphora resolution systems. In this paper, two methods for animacy identification are proposed and evaluated using intrinsic and extrinsic measures. The first method is a rule-based one which uses information about the unique beginners in WordNet to classify NPs on the basis of their animacy. The second method relies on a machine learning algorithm which exploits a WordNet enriched with animacy information for each sense. The effect of word sense disambiguation on the two methods is also assessed. The intrinsic evaluation reveals that the machine learning method reaches human levels of performance. The extrinsic evaluation demonstrates that animacy identification can be beneficial in anaphora resolution, especially in the cases where animate entities are identified with high precision.
    • Refined Salience Weighting and Error Analysis in Anaphora Resolution.

      Evans, Richard (The Research Group in Computational Linguistics, 2002)
      In this paper, the behaviour of an existing pronominal anaphora resolution system is modified so that different types of pronoun are treated in different ways. Weights are derived using a In genetic algorithm for the outcomes of tests applied by this branching algorithm. Detailed evaluation and error analysis is undertaken. Proposals for future research are put forward.
    • Web impact factors and search engine coverage

      Thelwall, Mike (MCB UP Ltd, 2002)
      Search engines index only a proportion of the web and this proportion is not determined randomly but by following algorithms that take into account the properties that impact factors measure. A survey was conducted in order to test the coverage of search engines and to decide whether their partial coverage is indeed an obstacle to using them to calculate web impact factors. The results indicate that search engine coverage, even of large national domains is extremely uneven and would be likely to lead to misleading calculations.
    • Which academic subjects have most online impact? A pilot study and a new classification process

      Thelwall, Mike; Vaughan, Liwen; Cothey, Viv; Li, Xuemei; Smith, Alastair G. (2013-06-28)