Document specification and search strategy using basic intersections and the probability measure of sets

Abstract

The usefulness of basic intersections and of the probability measure of sets for the formulation of document and search specifications in coordinate indexing systems is discussed. It is possible to formulate a search equation representing accurately the matching procedure between the specification of the request and that of the file item. The equation contains, besides the usual set of descriptive terms, a part comprising a matrix formulation of the truth tables of the file item and of the request. Through an operation between these matrix representations a new truth table referring to the subset of descriptive terms that are common to both, the request and the file item, is generated. The equation produces, furthermore, a general and quantitative criterion of relevance between request and file item. Certain numerical values of this criterion may be specified in advance, and thus the search operation may be controlled at will.