Pushdown dimension
نویسندگان
چکیده
Resource-bounded dimension is a notion of computational information density of infinite sequences based on computationally bounded gamblers. This paper develops the theory of pushdown dimension and explores its relationship with finite-state dimension. The pushdown dimension of any sequence is trivially bounded above by its finite-state dimension, since a pushdown gambler can simulate any finite-state gambler. We show that for every rational 0 < d < 1, there exists a sequence with finite-state dimension d whose pushdown dimension is at most d/2. This provides a stronger quantitative analogue of the well-known fact that pushdown automata decide strictly more languages than finite-state automata.
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عنوان ژورنال:
- Theor. Comput. Sci.
دوره 381 شماره
صفحات -
تاریخ انتشار 2007