17. A system for identifying relationships between text documents and structured variables pertaining to said text documents, comprising: an input device for inputting text documents; a processor for: forming categories of said text documents; counting occurrences of said structured variables, categories and combinations of structured variables and categories; calculating probabilities of occurrence of said combinations of structured variables and categories; and identifying a relationship between a structured variable of said structured variables and text documents included in a category of said categories based on a probability of occurrence of a combination of said structured variable and said category; and a display, for displaying said probabilities.
18. The system according to claim 17 , further comprising: a memory for storing occurrences of said structured variables, categories combinations of structured variables and categories, and probabilities of occurrences of said combinations of structured variables and categories.