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Preferred history semantics for iterated updates
A1 Platonix Technologies Ltd., 44 Petach Tikva Road, Tel Aviv 66183, Israel E-mail: shai@platonix.com A Institute of Computer Science, Hebrew University, Jerusalem 91904, Israel E-mail: lehmann@cs.huji.ac.il A3 Laboratoire d'Informatique de Marseille, ESA CNRS 6077, Universite de Provence, CMI, 39 rue Jolio-Curie, F-13453 Marseille Cedex 13, France E-mail: ks@gyptis.univ-mrs.fr
We give a semantics to iterated update by a preference relation on possible developments. An iterated update is a sequence of formulas, giving (incomplete) information about successive states of the world. A development is a sequence of models, describing a possible trajectory through time. We assume a principle of inertia and prefer those developments which are compatible with the information and avoid unnecessary changes. The logical properties of the updates defined in this way are considered, and a representation result is proved.
Keywords: Update, revision, knowledge, representation.