On Finite and Polynomial Ambiguity of Weighted Tree Automata
نویسنده
چکیده
We consider finite and polynomial ambiguity of weighted tree automata. Concerning finite ambiguity, we show that a finitely ambiguous weighted tree automaton can be decomposed into a sum of unambiguous automata. For polynomial ambiguity, we show how to decompose a polynomially ambiguous weighted tree automaton into simpler polynomially ambiguous automata and then analyze the structure of these simpler automata. We also outline how these results can be used to capture the ambiguity of weighted tree automata with weighted logics.
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