Ranking the Validity of Block Candidacies in Signature Files

A variation of the superimposed coding version of the signature file method is introduced. The processing of a user query is similar to that of the conventional method with one difference: the output is provided in a ordered (ranked) way. The latter is based on a credibility value reflecting the probability of each candidate block to pass the validation test rather than being a false drop. The principles, an analytical model, and simulation results of the new technique are presented. The model’s usefulness is the reduced I/O activity for cases where the user is only sampling the text base and is satisfied by retrieving a limited number of the many documents that qualify.