Learning from a Smarter Teacher

  • Leonor Becerra-Bonache
  • Adrian Horia Dediu
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5788)


We present a new learning algorithm introducing a helpful teacher who models the learners’ knowledge. Our algorithm, called learning from extensions (LEX), learns finite-state transducers using only one type of query called extension query. Our query was inspired by equivalence queries and counterexamples, but we show in this article that it is possible to learn efficiently finite state transducers using only extension queries (it is known that only with membership queries or only with equivalence queries is not possible). The teacher answers an extension query by connecting the new information asked by the learner with the information that the learner already knows. We prove that our new algorithm LEX discovers a target finite-state transducer in polynomial time. We also discuss briefly several complexity aspects and we give an example.


Mathematical Linguistics Automaton Learn Input Alphabet Membership Query Deterministic Finite Automaton 
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 2009

Authors and Affiliations

  • Leonor Becerra-Bonache
    • 1
    • 2
  • Adrian Horia Dediu
    • 1
    • 3
  1. 1.Research Group on Mathematical LinguisticsRovira i Virgili UniversityTarragonaSpain
  2. 2.Department of Computer ScienceYale UniversityNew HavenUSA
  3. 3.“Politehnica” University of BucharestBucharestRomania

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