In this section, two
methods to reduce the size of a problem, i.e. the number of ground facts and actions,
are presented. The first method refers to the identification and elimination of
objects, which are certainly not part of any solution. The second method
concerns the adoption of a numerical representation of resources, instead of
the problematic atom-based representation of numbers that has been used in
domains like mystery and freecell. Reducing the size of a problem
reduces the effort needed to solve it, especially in the pre-processing phase,
where distances for all facts of a problem have to be computed.
Ioannis
Refanidis
14-8-2001