Method and apparatus for scalable probabilistic clustering using decision trees

(54) METHOD AND APPARATUS FOR

SCALABLE PROBABILISTIC CLUSTERING
USING DECISION TREES

(75) Inventors: Mehran Sahami, Mountain View, CA (US); George Harrison John, San

Mateo, CA (US)

(73) Assignee: E.piphany, Inc., San Mateo, CA (US)

( * ) Notice: This patent issued on a continued prosecution application filed under 37 CFR 1.53(d), and is subject to the twenty year patent term provisions ol 35 U.S.C. 154(a)(2).

Subject to any disclaimer, the term ol this patent is extended or adjusted under 35 U.S.C. 154(b) by 0 days.

(21) Appl. No.: 09/304,509

(22) Filed: May 3, 1999

(65) Prior Publication Data

US 2003/0065635 Al Apr. 3, 2003

(51) Int. CI. G06N 5/02

Some embodiments ol the invention include methods lor identilying clusters in a database, data warehouse or data mart. The identified clusters can be meaninglully understood by a list ol the attributes and corresponding values lor each ol the clusters. Some embodiments ol the invention include a method lor scalable probabilistic clustering using a decision tree. Some embodiments ol the invention, perform linearly in the size ol the set ol data and only require a single access to the set ol data. Some embodiments ol the invention produce interpretable clusters that can be described in terms ol a set ol attributes and attribute values for that set ol attributes. In some embodiments, the cluster can be interpreted by reading the attribute values and attributes on the path from the root node ol the decision tree to the node ol the decision tree corresponding to the cluster. In some embodiments, it is not necessary for there to be a domain specific distance lunction lor the attributes. In some embodiments, a cluster is determined by identilying an attribute with the highest influence on the distribution ol the other attributes. Each ol the values assumed by the identified attribute corresponds to a cluster, and a node in the decision tree. In some embodiments, the CUBE operation is used to access the set ol data a single time and the result is used to compute the influence and other calculations.

59 Claims, 13 Drawing Sheets

OTHER PUBLICATIONS

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* cited by examiner