Data analyzing method for generating rules

• US 6,321,217 B1
• Filed: 04/29/1999
• Issued: 11/20/2001
• Est. Priority Date: 09/07/1994
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Ashida, Hitoshi, Ito, Yukiyasu, Takahashi, Yori, Taniguchi, Yoji, Maeda, Akira
• Primary Examiner(s): Davis, George B.
• Application Number:
  US09/301,595
• Time in Patent Office: 936 Days
• Field of Search: 706/45-48, 706/59, 706/61
• US Class Current: 706/47
• CPC Class Codes: G06N 5/025 Extracting rules from data
• CPC Class Codes: Y10S 707/99945 Object-oriented database structure processing
• CPC Class Codes: Y10S 707/99948 Application of database or data structure, e.g. distributed, multimedia, or image

Abstract

A data analyzing method for generating a rule based on data items in a data base, wherein the rule expresses relational features of the data items. The invention includes a user interface and a rule generation module. The rule generation module, in response to an input from the user via the user interface, selects data items for use in a conditional clause and a conclusion clause of a rule from the data items stored in the data base, converts, when the selected data items have numerical values, the numerical values into symbolic values and creates plural candidate rules each expressing a correlation between selected data items in a rule form having one or plural sets of item names and symbolic values. The rule generation module further calculates a criterion for evaluating strength of correlation between data items in each of the candidate rules, determines one or plural candidate rules having highest calculated criterion from the candidate rules, and outputs to the user via the user interface the one or plural candidate rules.

Claims

1. A data analyzing method of generating rules based on an analysis performed on a plurality of data items stored in a database by using a processing unit, said method comprising the steps of:

selecting data items in said database for use in an IF clause based on a designation inputted from an input device;

selecting data items in said database for use in a THEN clause based on a designation inputted from said input device;

converting numerical values into symbolic values when said selected data items include said numerical values;

when the value of a certain data item present within records included in said database to be analyzed includes a deficit value, adding a symbolic value indicative of the deficit value as a symbolic value of said data item;

determining, for each data item according to a statistical process, whether the symbolic value indicating the deficit value is to be used or not in the rule to be created; and

generating plural candidate rules by analyzing data items stored in said data base, each rule expressing a correlation between said selected data items,

wherein said rule is usable to describe the effect the data items in the database have on a selected data item.

2. A data analyzing method according to claim 1, wherein number of selectable data items is less than a predetermined value.

3. A data analyzing method of generating rules based on an analysis performed on a plurality of data items stored in a database by using a processing unit, said method comprising the steps of:

selecting data items in said database for use in an IF clause based on a designation inputted from an input device;

selecting data items in said database for use in a THEN clause based on a designation inputted from an input device;

converting numerical values into symbolic values when said selected data items include said numerical values;

when the value of a certain data item present within records included in said database to be analyzed includes a deficit value, adding a symbolic value indicative of the deficit value as a symbolic value of said data item;

deciding whether the symbolic value indicative of the deficit value is to be used automatically based on a dependence relation between said data item and a conclusion item; and

generating plural candidate rules by analyzing data items stored in said data base, each rule expressing a correlation between said selected data items,

wherein said rule is usable to describe the effect the data items in the database have on a selected data item.

4. A data analyzing method of generating rules based on an analysis performed on a plurality of data items stored in a database by using a processing unit, said method comprising the steps of:

selecting data items in said database for use in condition and conclusion clauses based on a designation inputted from an input device;

converting numerical values into symbolic values when said selected data items include said numerical values;

when the value of a certain data item present within records included in said database to be analyzed includes a deficit value which is determined according to an attribute of said data item, adding a symbolic value indicative of the deficit value as a symbolic value of said data item; and

generating plural candidate rules by analyzing data items stored in said data base, each rule expressing a correlation between said selected data items,

wherein said rule is usable to describe the effect the data items in the database have on a selected data item.