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Specialisation

To describe the algorithm we define first of all the specialisation of a mv-rule. Giving a mv-rule and a mv-atom, the mapping tex2html_wrap_inline2066 specialises the mv-rule with respect to that mv-atom generating a specialised mv-rule, or a new mv-atom if the rule had a single condition.

definition336

example357

We extend now the definition of specialisation of a mv-rule to that of the specialisation of a set of rules concluding the same atom p. In doing so, we select in turn a rule r to specialise. If its specialisation, with respect to a fact f, returns a new rule, that is, tex2html_wrap_inline2136 , then we substitute the rule by the specialised one in the agent's mental state representation, and the truth-value of p is not changed. If the specialisation returns a new interval for p, that is, tex2html_wrap_inline2142 , the rule is eliminated and a new truth-value for p is calculated by means of the Composition inference rule.

definition364

example381

The next definition accounts for the specialisation of an agent's mental state with respect to a set of atoms.

definition388

Note: The notation tex2html_wrap_inline2214 represents a modification of the function AG in such a way that from now on AG(f) = (I,R).

example398

To specialise a complete agent's mental state we will use each atom with definitive value in the mental state in turn to make specialisation steps that possibly will generate definitive values for other atoms to be later on used to specialise more the state. Clearly this process finishes because the number of atoms in any set of rules of the type considered is always finite. Hence the following algorithm

algorithm427

The complexity of this algorithm is tex2html_wrap_inline2294 where tex2html_wrap_inline2296 .



Josep Puyol-Gruart
Wed Jun 11 15:38:47 MET DST 1997