11. An information classification method for analyzing a configuration of data containing character information, comprising: character information extraction processing of extracting predetermined character strings from the character information of the data; labeling processing of converting the extracted character strings into a series of label strings by replacing each of the extracted character strings with a label indicating a class of the character string; and label appearance pattern estimation processing of estimating an appearance pattern that is defined as a set of different labels repeatedly appearing in the label strings, wherein, in the labeling processing, the extracted character strings are converted into the series of label strings by converting the extracted character strings into initial label strings, identifying, in the initial label strings, any series of the same label appearing at least twice in a row, and replacing any of the series of the same label with a single label, such that in resultant series of label strings, two or more of the same labels do not appear adjacently; the information classification method further comprising correspondence information storage processing of storing correspondence information defining correspondence between classes of extracted character strings and the labels to replace the character strings, wherein, in the labeling processing, based on the correspondence information, the extracted character string is replaced with the label for each class, and wherein: the correspondence information defines, for each of the extracted character strings, correspondence regarding a broader class or a narrower class relative to the class of classified character strings, the information classification method further comprises character information classification processing, wherein, in the character information classification processing, each label represented by the estimated appearance pattern is correlated with an optional class of each of the character strings before the replacement, a broader class relative to the optional class, or a narrower class relative to the optional class, and suitable character information suited to a predetermined combination is selected to classify the character strings extracted from the data.
11. An information classification method for analyzing a configuration of data containing character information, comprising: character information extraction processing of extracting predetermined character strings from the character information of the data; labeling processing of converting the extracted character strings into a series of label strings by replacing each of the extracted character strings with a label indicating a class of the character string; and label appearance pattern estimation processing of estimating an appearance pattern that is defined as a set of different labels repeatedly appearing in the label strings, wherein, in the labeling processing, the extracted character strings are converted into the series of label strings by converting the extracted character strings into initial label strings, identifying, in the initial label strings, any series of the same label appearing at least twice in a row, and replacing any of the series of the same label with a single label, such that in resultant series of label strings, two or more of the same labels do not appear adjacently; the information classification method further comprising correspondence information storage processing of storing correspondence information defining correspondence between classes of extracted character strings and the labels to replace the character strings, wherein, in the labeling processing, based on the correspondence information, the extracted character string is replaced with the label for each class, and wherein: the correspondence information defines, for each of the extracted character strings, correspondence regarding a broader class or a narrower class relative to the class of classified character strings, the information classification method further comprises character information classification processing, wherein, in the character information classification processing, each label represented by the estimated appearance pattern is correlated with an optional class of each of the character strings before the replacement, a broader class relative to the optional class, or a narrower class relative to the optional class, and suitable character information suited to a predetermined combination is selected to classify the character strings extracted from the data. 13. An information classification method according to claim 11 , wherein, in the character information classification processing, if there is any classification condition established by the character string of the same class, before processing of replacing two or more adjacent character strings of the same class with one label in the labeling processing, the label string is collated with the classification condition to execute classification based on the classification condition.