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Register a new userAlternative axiomatics and complexity of deliberative STIT theories
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Nicolas Troquard
Publication date
2007
fields
Informatics Engineering
and research's language is
English
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We propose two alternatives to Xus axiomatization of the Chellas STIT. The first one also provides an alternative axiomatization of the deliberative STIT. The second one starts from the idea that the historic necessity operator can be defined as an abbreviation of operators of agency, and can thus be eliminated from the logic of the Chellas STIT. The second axiomatization also allows us to establish that the problem of deciding the satisfiability of a STIT formula without temporal operators is NP-complete in the single-agent case, and is NEXPTIME-complete in the multiagent case, both for the deliberative and the Chellas STIT.
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