INFORMATION ANALYSIS AND METHOD

A hash dictionary stores identifiers of word-class sequences by unit of the word-class and appearance number. A node of each word in word-lattice includes the word-class, an interprocessing list, lists of next nodes and unprocessed antecedent nodes. The interprocessing list of the node directly linked from a start node stores the identifiers of word-class sequences for the word-class and the appearance number "1" in the hash dictionary. A list of processing nodes stores the nodes directly linked from the start node. A propagation section extracts one node from the list of processing nodes, extracts each next node of the one node from the list of next nodes, retrieves the identifiers of word-class sequences from the hash dictionary by the appearance number and the word-class of the each next node, respectively calculates a product of retrieved identifiers of the each next node and the identifiers in the interprocessing list of the one node, stores the product in the interprocessing list of the each next node, deletes the one node from the list of processing nodes, and adds the each next node in the list of processing nodes. This propagation process is repeated untill the list of processing nodes is empty.