Ambiguity and Communication

Juraj Hromkovic; Georg Schnitger

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arXiv · 0902.2140

Ambiguity and Communication

Juraj Hromkovic·Georg Schnitger

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Abstract

The ambiguity of a nondeterministic finite automaton (NFA) N for input size n is the maximal number of accepting computations of N for an input of size n. For all k, r 2 N we construct languages Lr,k which can be recognized by NFA's with size k poly(r) and ambiguity O(nk), but Lr,k has only NFA's with exponential size, if ambiguity o(nk) is required. In particular, a hierarchy for polynomial ambiguity is obtained, solving a long standing open problem (Ravikumar and Ibarra, 1989, Leung, 1998).

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Juraj Hromkovic, Georg Schnitger. 2009-02-12. Ambiguity and Communication. https://arxiv.org/abs/0902.2140

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