Nondeterministic space is closed under complementation
SIAM Journal on Computing
The probabilistic communication complexity of set intersection
SIAM Journal on Discrete Mathematics
On the distributional complexity of disjointness
Theoretical Computer Science
Exact lower time bounds for computing Boolean functions on CREW PRAMs
Journal of Computer and System Sciences
Communication complexity and parallel computing
Communication complexity and parallel computing
Communication complexity
Amplification of slight probabilistic advantage at absolutely no cost in space
Information Processing Letters
On the power of Las Vegas II: two-way finite automata
Theoretical Computer Science
On the power of Las Vegas for one-way communication complexity, OBDDs, and finite automata
Information and Computation
STACS '97 Proceedings of the 14th Annual Symposium on Theoretical Aspects of Computer Science
Tally Languages Accepted by Monte Carlo Pushdown Automata
RANDOM '97 Proceedings of the International Workshop on Randomization and Approximation Techniques in Computer Science
On the Power of Randomized Pushdown Automata
DLT '01 Revised Papers from the 5th International Conference on Developments in Language Theory
A Separation of Determinism, Las Vegas and Nondeterminism for Picture Recognition
COCO '00 Proceedings of the 15th Annual IEEE Conference on Computational Complexity
Las Vegas is better than determinism in VLSI and distributed computing (Extended Abstract)
STOC '82 Proceedings of the fourteenth annual ACM symposium on Theory of computing
Properties of Probabilistic Pushdown Automata
Properties of Probabilistic Pushdown Automata
On the size of randomized OBDDs and read-once branching programs for k-stable functions
STACS'99 Proceedings of the 16th annual conference on Theoretical aspects of computer science
On probabilistic pushdown automata
Information and Computation
Probabilistic length-reducing automata
MFCS'06 Proceedings of the 31st international conference on Mathematical Foundations of Computer Science
Growing Grammars and Length-reducing Automata
Fundamenta Informaticae - Non-Classical Models of Automata and Applications II
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There are non-context-free languages which are recognizable by randomized pushdown automata even with arbitrarily small error probability. We give an example of a context-free language which cannot be recognized by a randomized pda with error probability smaller than 1/2 - O(log2 n/n) for input size n. Hence nondeterminism can be stronger than probabilism with weakly-unbounded error. Moreover, we construct two deterministic context-free languages whose union cannot be accepted with error probability smaller than 1/3-2-Ω(n), where n is the input length. Since the union of any two deterministic context-free languages can be accepted with error probability 1/3, this shows that 1/3 is a sharp threshold and hence randomized pushdown automata do not have amplification. One-way two-counter machines represent a universal model of computation. Here we consider the polynomial-time classes of multicounter machines with a constant number of reversals and separate the computational power of nondeterminism, randomization and determinism.