INFORMATION RETRIEVAL SYSTEM

An information retrieval system retrieves stored information on the basis of incomplete or noisy retrieval key information within a realistic processing time. The information to be recalled is stored in neural network associative memory. Genetic algorithms are adopted to avoid a thorough retrieval of data in a huge breadth and depth of high-order space which must otherwise be searched due to ambiguity of retrieval key information. The information containing the given retrieval key is effectively sought. A processor employs a neural network. A memory is correctly recalled from partial inputs or inputs in which noise is extremely pronounced by repeating a sum-of-product operation of a firing pattern within a synapse coupling matrix and also threshold value processing.