Two Forms of Dependence in Propositional Logic: Controllability and Definability
نویسندگان
چکیده
We investigate two forms of dependence between variables and/or formulas within a propositional knowledge base: controllability (a set of variables X controls a formula if there is a way to fix the truth value of the variables in X in order to achieve to have a prescribed truth value) and definability (X defines a variable y if every truth assignment of the variables inX enables us finding out the truth value of y). Several characterization results are pointed out, complexity issues are analyzed, and some applications of both notions, including decision under incomplete knowledge and/or partial observability, and hypothesis discrimination, are sketched.
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تاریخ انتشار 1998