ANA : an assimilating and accommodating production system

In o r d e r fo r a sys tem to learn how to do new tasks, it must be capable of assimilation and accommodat ion . T h e assimilation capabil ity enables a system to relate unfamiliar s i tuat ions to s i tua t ions that it Knows about. Th rough assimilation, an unfamiliar situation is t r a n s f o r m e d , f o r a t ime, into a familiar situation. The accommodation capabil ity enables a sys tem to make s u c h t rans fo rmat ions permanent. ANA, the system descr ibed in this paper , is a p r o d u c t i o n s y s t e m that is capable of both assimilation and accommodation. Initially, A N A has a f e w m e t h o d s fo r accomplishing a va r ie ty of simple tasks. When it is g i ven a not too unfamil iar task , it p e r f o r m s that task b y analogy with one of the tasks it has a method fo r . W h e n it accompl ishes a new task (and typical ly this happens only after the method has b e e n e x t e n d e d t o handle p rob lems that it was not designed to cope with) , it s tores the knowledge of h o w it d i d the task. If A N A is subsequent ly faced with the same task, it recogn izes the task and p e r f o r m s it using the knowledge prev ious ly gained. This research was sponsored by the Defense Advanced Research Projects Aaencv (DOD) ARPA O r H o , Q K Q 7 ^ monitored by the Air Force Avionics Laboratory under Contract F3361 ?78.0 -1151. ' University Libraries Carnegie Mellon Universi** Pittsburgh PA 15213-389?