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Information Filtering: Selection Mechanisms in Learning Systems


Shaul Markovitch and Paul Scott. Information Filtering: Selection Mechanisms in Learning Systems. Machine Learning, 10:113-151 1993.


Abstract

Knowledge has traditionally been considered to have a beneficial effect on the performance of problem solvers but recent studies indicate that knowledge acquisition is not necessarily a monotonically beneficial process, because additional knowledge sometimes leads to a deterioration in system performance. This paper is concerned with the problem of harmful knowledge: that is, knowledge whose removal would improve a system's performance. In the first part of the paper a unifying framework, called the information filtering model, is developed to define the various alternative methods for eliminating such knowledge from a learning system. This framework identifies five locations in the information flow of a learning system where selection processes, called filters, may be inserted to remove potentially harmful knowledge. These filters are termed selective experience, selective attention, selective acquisition, selective retention, and selective utilization. The framework can be used by developers of learning systems as a guide for selecting an appropriate filter to reduce or eliminate harmful knowledge. In the second part of the paper, the framework is used to identify a suitable filter for solving a problem caused by the acquisition of harmful knowledge in a learning system called LASSY. LASSY is a system that improves the performance of a PROLOG interpreter by utilizing acquired domain specific knowledge in the form of lemmas stating previously proved results. It is shown that the particular kind of problems that arise with this system are best solved using a novel utilization filter that blocks the use of lemmas in attempts to prove subgoals that have a high probability of failing.


Keywords: Selective Learning, Utility Problem, Speedup Learning, Lemma Learning
Secondary Keywords:
Online version:
Bibtex entry:
 @article{Markovitch:1993:IFS,
  Author = {Shaul Markovitch and Paul Scott},
  Title = {Information Filtering: Selection Mechanisms in Learning Systems},
  Year = {1993},
  Journal = {Machine Learning},
  Volume = {10},
  Number = {2},
  Pages = {113--151},
  Url = {http://www.cs.technion.ac.il/~shaulm/papers/pdf/Markovitch-Scott-mlj1993.pdf},
  Keywords = {Selective Learning, Utility Problem, Speedup Learning, Lemma Learning},
  Secondary-keywords = {Harmful Knowledge, Information Filtering, Active Learning, Deductive Learning},
  Abstract = {
    Knowledge has traditionally been considered to have a beneficial
    effect on the performance of problem solvers but recent studies
    indicate that knowledge acquisition is not necessarily a
    monotonically beneficial process, because additional knowledge
    sometimes leads to a deterioration in system performance. This
    paper is concerned with the problem of harmful knowledge: that is,
    knowledge whose removal would improve a system's performance. In
    the first part of the paper a unifying framework, called the
    information filtering model, is developed to define the various
    alternative methods for eliminating such knowledge from a learning
    system. This framework identifies five locations in the
    information flow of a learning system where selection processes,
    called filters, may be inserted to remove potentially harmful
    knowledge. These filters are termed selective experience,
    selective attention, selective acquisition, selective retention,
    and selective utilization. The framework can be used by developers
    of learning systems as a guide for selecting an appropriate filter
    to reduce or eliminate harmful knowledge. In the second part of
    the paper, the framework is used to identify a suitable filter for
    solving a problem caused by the acquisition of harmful knowledge
    in a learning system called LASSY. LASSY is a system that improves
    the performance of a PROLOG interpreter by utilizing acquired
    domain specific knowledge in the form of lemmas stating previously
    proved results. It is shown that the particular kind of problems
    that arise with this system are best solved using a novel
    utilization filter that blocks the use of lemmas in attempts to
    prove subgoals that have a high probability of failing.
  }

  }