13. An article of manufacture, embodying logic to perform a method of mining a collection of data, comprising: a user interface for: receiving a collection of data, the collection of data comprising key words, wherein the key words comprise coherent character strings; visually displaying statistical information; and presenting a distribution of differences of unique concepts; and a processor embodying logic for: converting the collection of data into labeled data by grouping various types of data into a same format and assigning a label indicating a category of item contents, such that the labeled data is in analyzable condition for concept extraction, and wherein the labeled data comprises the label and a clause comprising the item contents; assigning a category to the key words, wherein the category references a concept so that the key words can be handled as concepts with a meaning; separating the clauses into pairs comprising an independent word and an attached word; assigning categories to the separated clauses using syntactic patterns and a category dictionary; generating, by syntactic analysis, a syntactic tree of a sentence comprising the separated clauses; receiving a syntactically analyzed sentence as input, identifying mutually dependent relationships between or among the categorized words, within each of the clauses; grouping the identified mutually dependent relationships into groups of related mutually dependent relationships; extracting the key words with mutually dependent relationships in the same sentence as labeled data with concepts, wherein the step of extracting key words comprises using a mutually dependent relationship extraction rule comprising a string of categories of arbitrary length to be extracted; and searching for the unique concepts, the unique concept being a concept whose statistical characteristic is distinguished beyond a threshold with the set to which it belongs; creating and keeping the statistical information.
13. An article of manufacture, embodying logic to perform a method of mining a collection of data, comprising: a user interface for: receiving a collection of data, the collection of data comprising key words, wherein the key words comprise coherent character strings; visually displaying statistical information; and presenting a distribution of differences of unique concepts; and a processor embodying logic for: converting the collection of data into labeled data by grouping various types of data into a same format and assigning a label indicating a category of item contents, such that the labeled data is in analyzable condition for concept extraction, and wherein the labeled data comprises the label and a clause comprising the item contents; assigning a category to the key words, wherein the category references a concept so that the key words can be handled as concepts with a meaning; separating the clauses into pairs comprising an independent word and an attached word; assigning categories to the separated clauses using syntactic patterns and a category dictionary; generating, by syntactic analysis, a syntactic tree of a sentence comprising the separated clauses; receiving a syntactically analyzed sentence as input, identifying mutually dependent relationships between or among the categorized words, within each of the clauses; grouping the identified mutually dependent relationships into groups of related mutually dependent relationships; extracting the key words with mutually dependent relationships in the same sentence as labeled data with concepts, wherein the step of extracting key words comprises using a mutually dependent relationship extraction rule comprising a string of categories of arbitrary length to be extracted; and searching for the unique concepts, the unique concept being a concept whose statistical characteristic is distinguished beyond a threshold with the set to which it belongs; creating and keeping the statistical information. 19. The article of manufacture of claim 13 wherein the data is inquiry data provided by customers.