Machine Learning

, Volume 9, Issue 2–3, pp 147–164 | Cite as

Learning conjunctions of Horn clauses

  • Dana Angluin
  • Michael Frazier
  • Leonard Pitt


An algorithm is presented for learning the class of Boolean formulas that are expressible as conjunctions of Horn clauses. (A Horn clause is a disjunction of literals, all but at most one of which is a negated variable.) The algorithm uses equivalence queries and membership queries to produce a formula that is logically equivalent to the unknown formula to be learned. The amount of time used by the algorithm is polynomial in the number of variables and the number of clauses in the unknown formula.


Propositional Horn sentences equivalence queries membership queries exact identification polynomial time learning 


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Copyright information

© Kluwer Academic Publishers 1992

Authors and Affiliations

  • Dana Angluin
    • 1
  • Michael Frazier
    • 2
  • Leonard Pitt
    • 2
  1. 1.Computer ScienceYale UniversityNew Haven
  2. 2.Computer ScienceUniversity of IllinoisUrbana

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