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Ordering Mental Actions

Axiom gif defines a total order Better on the set of appropriate mental actions for a mental situation. The predicate tex2html_wrap_inline716 is true if mental action tex2html_wrap_inline670 is better than mental action tex2html_wrap_inline720 at mental situation m. Therefore, tex2html_wrap_inline670 will be selected before tex2html_wrap_inline720 at mental situation m in the process of searching for a solution.

The preference relation Better is a powerful mechanism for the declarative formalization of heuristics [10] [2] [17] [16]. Here we use only two simple heuristics: (1) actions appropriate for goals in upper levels of the goal stackgif are preferred to actions appropriate for goals in lower levels; (2) if two actions are appropriate for the same goals, they are selected in alphabetic order tex2html_wrap_inline730 .


Josefina Sierra
Tue Jul 21 09:26:01 PDT 1998