ABSTRACT
According to current theories of cognitive skill acquisition, new problem solving rules are constructed by proceduralization, production compounding, chunking, syntactic generalization, and a variety of other mechanisms. All these mechanisms are assumed to run rather quickly, so a rule's acquisition should be a matter of a few seconds at most. Such “learning events” might be visible in protocol data. This paper discusses a method for locating the initial use of a rule in protocol data. The method is applied to protocols of subjects learning three tasks: a river crossing puzzle, the Tower of Hanoi, and a topic in college physics. Rules were discovered at the rate of about one every half hour. Most rules required several learning events before they were used consistently, which is not consistent with the one-trial learning predicted by explanation-based learning methods. Some observed patterns of learning events were consistent with a learning mechanism based on syntactic generalization of rules. Although most rules seem to have been acquired at impasses-occasions when the subject does not know what to do next- there were clear cases of rules being learned without visible signs of an impasse, which does not support the popular hypothesis that all learning occurs at impasses.
