Patent ID: 7051017

Claim:
An information retrieval system comprising: an information file processing component that is structured to generate a term-document matrix to represent electronic information files stored in a computer system, each element in the term-document matrix indicating a number of occurrences of a term within a respective one of the electronic information files; and generate a term-spread matrix to produce a weighted autocorrelation of the generated term-document matrix, the term-spread matrix indicating an amount of variation in term usage in the information files and the extent to which terms are correlated; a query mechanism that is structured to receive a query consisting of at least one term and generate a query vector based upon use received query, wherein the query vector has as many elements as the rows of the term-spread matrix; and an optimization engine that is structured to formulate, based upon the term-spread matrix and query vector, a constrained optimization problem description, wherein the choice of a stabilization parameter in the problem description determines the extent of a trade-off between a degree of fit and the stability of all solutions to the constrained optimization problem description; generate a solution vector to the constrained optimization problem description, the vector including a plurality of document weights, each one of the plurality of document weights corresponding to one of each the information files, wherein each of the document weights reflects a degree of correlation between the query and the corresponding one of the information files; and providing an information response reflecting the document weights.