Accession Number : AD0721671

Title :   Interrogating a Relational Data File: Remarks on the Admissibility of Input Queries,

Corporate Author : RAND CORP SANTA MONICA CALIF

Personal Author(s) : Kuhns,J. L.

Report Date : NOV 1970

Pagination or Media Count : 57

Abstract : The report continues the work, of developing and implementing a theory of data retrieval for a computerized question-answering system in which the queries are represented as formulas of the predicate calculus and the data base consists of atomic sentences. Algorithms for processing queries involving a full vocabulary of binary operators are given. It is shown that definite formulas having at most two levels of operators from certain minimal operator sets can always be transformed into proper formulas (i.e., formulas consiting entirely of definite subformulas) and algorithms for these 'admissibility' transformations are given. In addition to the conventional operators, a new form of universal quantification is proposed for query systems. Rules for evaluation are given, and it is shown that the class of definite formulas is closed under this new 'generalized universal quantification.' Finally, theoretical limitations on methods of determining propriety through admissibility transformations are discussed. (Author)

Descriptors :   (*INFORMATION RETRIEVAL, MATHEMATICAL LOGIC), DECISION MAKING, DATA PROCESSING, COMPUTER PROGRAMMING, LINGUISTICS, LEARNING MACHINES, THEOREMS

Subject Categories : Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE