Abstract:
The theory of introspective multistrategy learning proposes that three transformations must occur to learn effectively from a performance failure in an intelfigent system: Blame assignment, deciding what to learn, and learning-strategy construction. The Meta-AQUA system is a multistrategy learner that operates in the domain of story-understanding failures and is designed to evaluate this learning approach. We discuss experimental results supporting the hypothesis that introspection facilitates learning in a multistrategy environment. In an empirical study, Meta-AQUA performed significantly better with a fully introspective mode than with a reflexive mode in which learning goals were ablated. In particular, the restdts lead to the conclusion that the process which posts learning goals (deciding what to learn) is a necessary transformation if negative interactions between learning methods are to be avoided and if learning is to remain effective. Moreover, we show that because learning algorithms. can negatively interact, the arbitrary ordering of learning methods can actually lead to worse system performance than no learning at all. The goals of this research are to better understand the interactions between learning algorithms, to determine the role of introspective mechanisms when integrating them, and to more firmly establish the conditions under which such an approach is warranted (and those under which it is not).