ylfink@water.waterloo.edu (ylfink) (12/13/88)
DEPARTMENT OF COMPUTER SCIENCE UNIVERSITY OF WATERLOO SEMINAR ACTIVITIES ARTIFICIAL INTELLIGENCE SEMINAR - Friday, December 16, 1988 Professor Larry Rendell, Department of Computer Science, University of Illinois at Urbana-Champaign, will speak on ``Learning Hard Concepts''. TIME: 11:30 AM ROOM: DC 1304 ABSTRACT Hard boolean concepts have arbitrary compositions of conjuncts and disjuncts. Hard graded concepts are arbitrary functions having any composition of disjuncts, modes, or peaks. If instances are k-tuples of attribute values labeled with (binary or graded) class membership values, learning hard concepts is uniformly difficult for a class of methods that do ``similarity based learning'' or ``selective induction''. The problem has been named differently in different areas of research: ``curve fitting'' and ``density function estimation'' (statistics), ``discriminant boundary'' detection (pattern recognition), ``finding weights'' (neural systems), and ``concept learning'' (artificial intelligence). The poor behavior of these basic methods leads to techniques for the creation of ``better'' attributes through ``constructive induction.'' This talk characterizes the problem and presents an algorithm schema designed to use domain knowledge when available. The analysis shows how constructive induction can alleviate difficulties of selective induction.