Chomsky hierarchy

About: Chomsky hierarchy is a research topic. Over the lifetime, 601 publications have been published within this topic receiving 31067 citations. The topic is also known as: Chomsky–Schützenberger hierarchy.

On Learning Smullyan's Elementary Formal Systems: Towards an Efficient Learning Method for Context-Sensitive Languages*

Abstract: Summary In this paper, we introduce a new class of representations for formal languages that is defined by Smullyan's elementary formal systems for the problem of learning formal languages. The class of representations is a natural extension of context-free grammars, and the languages defined by these representations lie between context-free languages and context-sensitive languages and contain some important classes of formal languages such as Angluin's pattern languages, thus enabling us to take an unified view of learning formal languages. We demonstrate an efficient algorithm for learning these representations in the framework of learning by making queries to a teacher modeled on Angluin's approach to learning k -bounded context-free grammars. Our algorithm may be viewed as a natural and powerful extension of Angluin's algorithm.

AtoCC: learning environment for teaching theory of automata and formal languages

Abstract: The learning environment AtoCC is presented to be of use in teaching abstract automata, formal languages, and some of its applications in compiler construction. From a teacher's perspective AtoCC aims to address a broad range of different learning activities forcing the students to actively interact with the subjects being taught.

The algebraic approach II: dioids, quantales and monads

Abstract: The algebraic approach to formal language and automata theory is a continuation of the earliest traditions in these fields which had sought to represent languages, translations and other computations as expressions (e.g. regular expressions) in suitably-defined algebras; and grammars, automata and transitions as relational and equational systems over these algebras that have such expressions as their solutions. As part of a larger programme to algebraize the classical results of formal language and automata theory, we have recast and generalized the Chomsky hierarchy as a complete lattice of dioid algebras. Here, we will formulate a general construction by ideals that yields a family of adjunctions between the members of this hierarchy. In addition, we will briefly discuss the extension of the dioid hierarchy to semirings and power series algebras.