INVESTIGADORES
CHESÑEVAR Carlos Ivan
artículos
Título:
Computing Generalized Specificity
Autor/es:
CARLOS IVÁN CHESÑEVAR; FRIEDER STOLZENBURG; ALEJANDRO GARCÍA; GUILLERMO SIMARI,
Revista:
JOURNAL OF APPLIED NON-CLASSICAL LOGICS
Referencias:
Lugar: Hermes-Elsevier; Año: 2003 vol. 13 p. 87 - 113
ISSN:
1166-3081
Resumen:
Most formalisms for representing common-sense knowledge allow
incomplete and potentially inconsistent information. When strong
negation is also allowed, contradictory conclusions can arise. A
criterion for deciding between them is needed. The aim of this paper
is to investigate an inherent and autonomous comparison criterion,
based on specificity as defined in \cite{Poo85,SL92}. In contrast to
other approaches, we consider not only defeasible, but also strict
knowledge. Our criterion is context-sensitive, i.e. preference among
defeasible rules is determined dynamically during the dialectical
analysis.
We show how specificity can be defined in terms of two different
approaches: \emph{activation sets} and \emph{derivation trees}. This
allows us to get a more syntactic criterion that can be implemented
in a computationally attractive way. The resulting definitions may be
applied in general rule-based formalisms. We present theorems linking
both characterizations. Finally we discuss other frameworks for
defeasible reasoning in which preference handling is considered
explicitly.