Approximate Bit Vectors for Fast Unification

  • Matthew Skala
  • Gerald Penn
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6878)


Bit vectors provide a way to compute the existence of least upper bounds in partial orders, which is a fundamental operation needed by any unification-based parser. However, bit vectors have seen relatively little adoption because of their length and associated speed disadvantages. We present a novel bit vector technique based on allowing one-sided errors; the resulting approximate bit vectors can be much shorter than the minimum lengths required by existing techniques that would provide exact answers. We give experimental results showing that our approximate vectors give accurate enough answers to be useful in practice.


Partial Order Vector Length Statistical Machine Translation Maximal Type Stochastic Local Search 
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 2011

Authors and Affiliations

  • Matthew Skala
    • 1
  • Gerald Penn
    • 2
  1. 1.University of ManitobaWinnipegCanada
  2. 2.University of TorontoTorontoCanada

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