On Specificity in Default Logic
نویسنده
چکیده
The applicability of lexicographic comparison in nonmonotonic reasoning wi th specificity is investigated A priority mechanism based on lexicographic comparison is defined for Rciter's default logic The following principle earlier used by Geffner and Pearl in conditional entail ment is used as the basis for specificity-based priorities for normal default theories for each rule there is a context where it ma> not be de feated by any other rule A method for com puting priorities according to the principle is given Connection to earlier work is discussed
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