Abstract
We present a Preferential Default Description Logic (pddl) based on weighted defaults and show that the preferential entailment relation
∑ satisfies all properties of system P and Rational Monotonicity. The main characteristics of this pddl is that it uses an ordering between multisets of defaults for priorization, treats defaults similar to material implications, and adheres strictly to the principle of exception minimization.
We furthermore show how maximization of default applications can be consistently combined with
∑ without violating exception minimization. Furthermore, the resulting entailment relation
F ∑ still satisfies all properties of system P.
We then develop a proof theory for
∑ based on default spaces, which shows that
∑ is decidable if the underlying dl is.
∑ can be syntactically characterized by strict entailment from all maximal default spaces and can thus be computed by an exponential algorithm.
The project KIT-VM11 is supported by the German Federal Minister of Research and Technology (BMFT) under contract 01 IV 101Q8.
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© 1994 Springer-Verlag Berlin Heidelberg
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Quantz, J.J., Suska, S. (1994). Weighted defaults in description logics: Formal properties and proof theory. In: Nebel, B., Dreschler-Fischer, L. (eds) KI-94: Advances in Artificial Intelligence. KI 1994. Lecture Notes in Computer Science, vol 861. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-58467-6_16
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DOI: https://doi.org/10.1007/3-540-58467-6_16
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