AUTOMATIC DATA CLASSIFICATION The standard approach to classification in much of artificial intelligence and statistical pattern recognition research involves partitioning of the data into separate subsets, known classes. AUTOCLASS III, from NASA Ames Research Center, uses the Bayesian approach in which classes are described by probability distributions over the attributes of the objects, specified by a model function and its parameters. The calculation of the probability of each object's membership in each class provides a more intuitive classification than absolute partitioning techniques. AUTOCLASS III is applicable to most data sets consisting of independent instances, each described by a fixed length vector of attribute values. An attribute value may be a number, one of a set of attribute specific symbols, or omitted. The user specifies a class probability distribution function by associating attribute sets with supplied likelihood function terms. AUTOCLASS then searches in the space of class numbers and parameters for the maximally probable combination. It returns the set of class probability function parameters, and the class membership probabilities for each data instance. AUTOCLASS III, ARC-13180, is written in Common Lisp, and is designed to be platform independent. This program has been successfully run on Symbolics and Explorer Lisp machines and has also been successfully used with the following implementations of Common LISP on the Sun: Franz Allegro CL, Lucid Common Lisp, and Austin Kyoto Common Lisp and similar UNIX platforms; under the Lucid Common Lisp implementations on VAX/VMS v5.4, VAX/Ultrix v4.1, and MIPS/Ultrix v4, rev. 179; and on the Macintosh personal computer. The minimum Macintosh required is the IIci. An electronic copy of the documentation is included on the distribution medium. Program $900; documentation $21. COSMIC The University of Georgia 382 East Broad St, Athens, GA 30602-4272 706-542-3265, FAX: 706-542-4807 +---------------------------------------------------------------+ | From the America Online - New Product Information Services | +===============================================================+ | This information was processed from data provided by the | | above mentioned company. For additional details, contact the | | company at the address or telephone number indicated above. | | All submissions for this service should be addressed to | | BAKER ENTERPRISES, 20 Ferro Drive, Sewell, NJ 08080 U.S.A. | +---------------------------------------------------------------+