Chomsky Hierarchy

(Redirected from Chomsky hierarchy)
Jump to navigation Jump to search

A Chomsky Hierarchy is a Formal Language that ...




  • (Wilson, 2012) ⇒ Bill Wilson, (1998 - 2012). “The Natural Language Processing Dictionary"
    • The Chomsky hierarchy is an ordering of types of grammar according to generality. The classification in fact only depends on the type of grammar rule or production used. The grammar types described in COMP9414 included:
      • unrestricted grammars (rules of the form a → b with no restrictions on the strings a and b)
      • context sensitive grammars (rules of the form a → b with the restriction length(a) <= length(b))
      • context free grammars (rules of the form X → b where X is a single non-terminal symbol)
      • regular grammars (rules of the form X → a and X → aN where X and N are non-terminal symbols, and a is a terminal symbol.)


  • (Chomsky, 1957) ⇒ Noam Chomsky. (1957). “Syntactic Structures." Mouton de Gruyter.
    • Introduction: Noam Chomsky, Syntactic Structures was the snowball which began the avalanche of the modem "cognitive revolution". The cognitive perspective originated in the seventeenth century and now construes modern linguistics as part of psychology and human biology. Depending on their initial conditions, children grow into adults with various language systems, some variety of Japanese if raised in Tokyo and Cornish English if raised in the village of Polperro. Linguists seek to describe the mental systems that Japanese or Cornish people have, their language "organs". These systems are represented somehow in human mind/brains, are acquired on exposure to retrain kinds of experiences, and art used in certain ways during speech comprehension or production and for a variety of purposes: communication, play, affects, group identity, etc. Linguists also specify the genetic information, common to the species, which permits the growth of mature language organs in Cornish, Japanese, Dutch, Kinande and Navaho children.