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Soar is able to use knowledge from a variety of sources simultaneously
due to the
parallel nature of the
elaboration phase.
However,
problem spaces also provide a
natural compartmentalization of unrelated knowledge sources. The combination
of these two considerations makes Soar ideal for problems in which a
lot a knowledge is available, avoiding overloads when there is
a preponderance of data and knowledge.
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The compartmentalization of knowledge provided by problem spaces also gives
Soar the ability to manage the complexity of the environment even though it
has limited resources. Some additional
ability may come from
match-based attention and the ability
to recognize familiar events in the midst of complex inputs via the
associational character of
long-term memory.
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Search
Soar was designed as a mechanism to realize the
weak methods. As such, it is ideal for
problems that involve search.
Problem Spaces provide a definition
of the search space and the operators that may be applied.
Chunking allows knowledge gained during
search to be cached, resulting in problem solving that is initially
search intensive but that becomes more
routine as problem solving progresses.
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Soar's universal learning mechanism,
chunking, makes it particularly
applicable to problems in which a considerable performance improvement
can be realized through learning search control or general problem
knowledge. Learning cost is minimized in Soar because the
impasse mechanism provides
the necessary knowledge about when and what to learn.
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Encoding and decoding productions
allow Soar to monitor an immense amount of changing detail. The
match-based attention mechanism
of the
production system allows
salient behavior even in the midst
of this perceptual diversity. Thus, Soar is able to maintain its
reactivity in dynamic environments.
One limitation here is that the environment should require reaction
no faster than the
decision phase.
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Soar can act as a general
problem solver and is just as applicable
to environments which are stable as to dynamic ones. In particular, Soar
has been applied to many games (such as the 8-puzzle and Towers of Hanoi)
which have very static environments (nothing changes except through the
direct action of the agent). Although Soar may not be as
efficient as special-purpose techniques
for the particular problem, it may certainly be applied and achieve
success in these domains.
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Soar is chiefly able to operate in uncertain environments due to its
utilization of a
minimum commitment strategy. This
allows the specifics surrounding an event to be instantiated at run-time
rather than being necessarily anticipated beforehand. Additionally, the
generalization of
chunking also alleviates the need to
be certain of forthcoming events; if the events are similar in scope (or
if a variety of different events have been experienced by the system), the
learned chunks will apply to the new situation.
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Unfortunately, Soar requires consistent environments, ones whose properties
do not change over time. This is a direct result of the
impenetrability and
permanence of productions. An additional
problem is that
learned chunks also reside in this
memory, resulting in improper (and perhaps erroneous) behavior when the
appropriate response to the same environment changes significantly.
This problem is currently being addressed and is discussed among the
issues.
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