
3.13 representing proCeDural KnowleDge 75
much for machines. Hierarchical classification leads to enhanced generaliza-
tion, information reduction, and significantly increased performance.
3.13.3 Frames
Frames—first proposed by Marvin Minsky, who has made important
contributions to AI, cognitive psychology, computational linguistics, and
robotics—have been the primary attempt to mimic human reasoning and
knowledge in a hierarchical representation. They are descriptions of concep-
tual and default knowledge about a given entity. Frames can be logical or
physical. Examples include a bike, a teacher, and a course. A frame contains