23. The non-transitory computer-readable storage medium according to claim 22 , wherein in Step (b), the training data candidates assigned a specified label in the cluster containing the specified label at or above a predetermined percentage are used as the training data having the specified label.
23. The non-transitory computer-readable storage medium according to claim 22 , wherein in Step (b), the training data candidates assigned a specified label in the cluster containing the specified label at or above a predetermined percentage are used as the training data having the specified label. 25. The non-transitory computer-readable storage medium according to claim 23 , wherein in Step (b), the degree of cluster membership is obtained for training data candidates that are not assigned the specified label in the cluster containing the specified label at or above a predetermined percentage, and the training data candidates for which the obtained degree is not lower than a threshold value are used as training data, while the training data candidates for which the obtained degree is less than the threshold value are deleted from the entire set of training data candidates.