Abstract: In an analogically similar word production apparatus, based on three inputted unit strings, an analogically similar word which is a word analogically similar to inputted unit strings is produced at high speed without using attributes and without any finite state automaton. A pseudo-distance matrix memory stores therein only matrix elements sufficient for computation of limited pseudo distances between two letter strings, out of the elements of two pseudo-distance matrices, and more specifically, matrix elements including diagonal elements are computed by a preprocessing section and then stored in the pseudo-distance matrix memory.

Abstract: Provided is a similarity search apparatus for searching data at a higher speed than that of the prior art without limiting the types of letter of a search key. A unit position correspondence memory stores therein a table that expresses the ordinal number among units at which each unit in a search key inputted by means of a keyboard has appeared within the search key. A search section refers to the table stored in the unit position correspondence memory and operates every time units are read out one by one from a database memory including a plurality of units to generate a plurality of status parameters each of which includes a similarity, a position of coincidence and a skip number, which express with what number of units from the top of the search key the units read out from the database have coincided at what degree of similarity, and express how many units in the database have been skipped over subsequently.