New Tractable Cases in Default Reasoning from Conditional Knowledge Bases
نویسندگان
چکیده
We present new tractable cases for default reasoning from conditional knowledge bases. In detail, we introduce q-Horn conditional knowledge bases, which allow for a limited use of disjunction. We show that previous tractability results for "-entailment, proper "-entailment, and zand z+-entailment in the Horn case can be extended to the q-Horn case. Moreover, we present feedback-freeHorn conditional knowledge bases, which constitute a new, meaningful class of conditional knowledge bases. We show that the maximum entropy approach and lexicographic entailment are tractable in the feedback-free-Horn case. Our results complement and extend previous results, and contribute in refining the tractability/intractability frontier of default reasoning from conditional knowledge bases.
منابع مشابه
Default reasoning from conditional knowledge bases: Complexity and tractable cases
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تاریخ انتشار 2000