Abstract: On recognizing first through P-th input patterns as first through P-th recognized patterns (P being greater than one) by using a plurality of reference patterns and a plurality of memorized indentifiers identifying the reference patterns, a processing circuit processes the first through the P-th input patterns into first through Q-th provisional patterns different from one another, where Q is not greater than the above-mentioned plurality. A calculating circuit calculates dissimilarity degrees had by the reference patterns relative to the first through the Q-th provisional patterns to select, with repetition allowed as selected patterns, the reference patterns which have the dissimilarity degrees less than a predetermined degree. The calculating circuit thereby selects R particular identifiers and S different identifiers from the memorized identifiers, where R plus S is not greater than P and is not less than the plurality.