Showing papers on "Formal grammar published in 1982"

Explanations in the Study of Child Language Development

Abstract: Preface 1. Criteria for adequacy 2. Jakobson's theory of phonological development 3. Early lexical development 4. The acquisition of relational terms 5. The development of formal grammar 6. Semantic approaches to syntactic development 7. The development of speech-acts 8. Cognitive reductions 9. Social reductions 10. Learnability and mechanisms of learning Notes Bibliography Index.

Linguistic Decision Structures for Hierarchical Systems

Abstract: The development of a new hierarchical linguistic-based learning control structure for complex systems is described. The complete system will be able to interact with a human operator in a high-level language at the highest level of the hierarchy and will be able to control detailed motions of a complex physical system at the lowest level of the hierarchy. Each level of the hierarchy is defined by a formal grammar which can generate exactly the class of admissible control actions at that level. A new linguistic structure, the linguistic decision schema, is proposed to specify the mapping between linguistic elements in adjacent levels. In the most general form, the decision schema incorporates a learning algorithm to obtain asymptotically optimal mappings for control under stochastic environments.

Formal Semantics of Natural Language

Abstract: ion ( x. t) I The function that maps x to t. I t is called the body of the abstraction. I The free occurences of x in t are bound in ( x. t). Curryfication g(x, y) = x+ y fx(y) = x+ y g0(x) = fx g0(x)(y) = fx(y) = x+ y = g(x, y) λ-Notation -Notatation

Further developments toward using formal grammar as a design tool

Abstract: First, we will describe how some kinds of “cognitive” information can be incorporated into a formal grammar. This information will permit us to describe a system, formally, for different classes of users. Most current models are limited to specific classes of users. They do not, for example, permit us to describe a system differently for naive and for expert users.Next, we will describe, explicitly, the prediction process.The last point to be discussed is our general approach to testing the use of formal grammar as a design tool. This idea is being developed and tested using an IBM editor as an example.

Syntax Directed Program Modularization

Abstract: The intent of this paper is to illustrate the following general ideas: -- Use of the context free grammar of a programming language as an integrated part of its programming system. -- Reconsideration of the border line between language and system. -- Systematic modularization of programs for the various translation phases. The specific ideas presented in this paper are language independent methods for handling: -- Modularization of programs. -- Separate translation in the form of context sensitive parsing (type checking) of modules. -- Protection of part of a module, e.g. protection of the representation of an abstract data type. The mechanism for modularization is unusual as it is based on the context-free syntax of the language. A module may be a sentential form generated by any nonterminal of the grammar.

Dense Hierarchies of Grammatical Families

Abstract: A technique ts presented for constructing dense hierarchies of grammatical subfamthes of context-free languages The question of \"where\" such dense hierarchies may lie is also investigated Infinite hierarchies of successors are studied. The major open problems concern questions deahng with fimte grammar forms Categories and SubJect Descriptors. F 4 3 ]Mathematical Logic and Formal Languages] Formal Languages-classes defined by grammars or automata (e g, context-free languages, regular sets, recursive sets) General Terms Languages, Theory Addmonal

Correction to "Error-Correcting Parsers for Formal Languages"

Abstract: In our earlier paper1 we proposed an algorithm S for error-correcting parsing of formal languages. It is found recently that two additional CS conditions and a routine for detecting infinite loop are required for the algorithm S.

An advanced programming language definition and domain correctness of programs

Abstract: Program execution is not adequately reflected in usual syntactic programming language definition by formal grammar, although either actual or mental execution is referred to during reading (tracing) and correctness proving. An advanced programming languages definition associates in input/output variables, the domain, and the computable function with each program. It is based on a computer automaton when inputs from In, states from St are viewed as instructions, memory states, respectively. The heart of it, is its transition (next-state) function trans: In x St → St.Arithmetic symbols occuring in a program are interpreted (by programmer) in usual infinite arithmetics during problem solving while they are interpreted (by a computer) in finite computer arithmetics when the program is executed. The program is characterized by its execution-semantics expressed in its control (next-instruction) function contr: In x St → In. The discrepancy between finite and infinite interpretation-semantics are studied as suggested in [Hoar 69], in particular, the two computable functions are compared.Total and partial correctness [Mann 74] does not show which interpretation should be considered; therefore, the third component of a proof of correctness, a domain correctness proof, is added.

Derivational complexity of context-free grammars

Abstract: Derivational complexity of context-free grammars is studied. Minimal grammar-dependent upper bounds are determined both on the derivational time complexity, that is, the number of derivation steps needed to derive a sentence of given length, and on the derivational space complexity, that is, the length of the longest sentential form needed in the derivation. In addition to general context-free grammars, these upper bounds are also determined specifically for ɛ -free grammars, non-left-recursive and non-right-recursive grammars, and for LL( k ) grammars. The results might prove useful in parser optimization, because the complexity of a parser is closely related to the derivational complexity of the underlying context-free grammar.

EPSILON: A System Description Language

Abstract: This paper presents the Epsilon language and defines its formal syntax and semantics. Epsilon is a language for the description of systems, which contain concurrent components, some of these being edp-equipment or by other means representing highly structured information handling. The actions consist of continuous changes described by equations, of communication between the components and of normal algorithmic actions. Epsilon may be used for the description of computer systems together with their environments, e.g. production equipment and human operators. Parts of such a description may serve as the system specification from which computer programs are developed. Epsilon is not itself an implementable language. This paper defines the semantics of Epsilon by means of a model based on high-level Petri nets, i.e. a model founded on the notion of concurrency. The model also uses denotational semantics and equation systems.

Creativity and linguistic theory : a study of the creative aspect of language

Abstract: The notion of creativity has been used by many theorists to describe that aspect of language which enables a language user to use language in a novel way or to devise new forms of language. Chomsky especially uses the "creative aspect of language use" to describe the innovative uses of language. This study explores the notion of creativity in linguistic theory. An examination is made of its application by Chomsky, from his earliest work on. At least two different notions are distinguishable: rule-governed creativity and rule-changing creativity. The former is shown to be a formal property of the syntactic system and creative in a mechanical sense only. The latter is an aspect of the semantic system, but is left largely unexplored by Chomsky. An assessment is made of comments by other theorists on the notion of creativity and these are related to the Chomskian analysis. The distinction between rule-governed and rule-changing creativity is confirmed. Den Ouden (1975) is criticised in some detail as a superficial treatment of the topic. The semantic nature of creativity in language is confirmed. The theory of metaphor is treated as an example of creativity in language. Metaphor is clearly a meaning-based language device and has traditionally been described as a creative mechanism. The range of metaphor theories is reviewed and a synthesis is attempted, based on the Mooij (1976) model, with some assistance from Ricoeur (1978). The psycho-linguistic literature on metaphor is reviewed in the light of this model, and a working description derived, based on Ortony's (1979) concept of non-literal similarity. This description implies that there exists a capacity in language to move beyond the literal rules of syntax and semantics, as described in standard linguistic theory, and still produce a comprehensible utterance. Therefore, the existing models of language are based on rules of syntax and semantics which are too restrictive, and there may exist a supra syntactic-semantic device which enables comprehension of syntactically or semantically anomalous utterances. This is the creative capacity of language. The work of De Beaugrande is considered as an attempt to build this creative capacity into the formal description of language. Language is characterised as an intersystem in which various systems of rules and elements interact. This interaction produces meaning bearing texts. The rules and elements are subject to modification; only the meaning function of the text is immutable. Creativity, then, is the formal capacity for intersystem modification.