Definition: A Turing machine in which some transitions are random choices among finitely many alternatives.
See also alternating Turing machine, nondeterministic Turing machine, oracle Turing machine, universal Turing machine, NP, RP, ZPP, BPP.
Note: The typical, deterministic Turing machine (TM) can be seen as a probabilistic TM with no more than one alternative for each transition. A nondeterministic TM is a probabilistic TM ignoring the probabilities.
From Algorithms and Theory of Computation Handbook, page 29-20, Copyright © 1999 by CRC Press LLC. Appearing in the Dictionary of Computer Science, Engineering and Technology, Copyright © 2000 CRC Press LLC.
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Entry modified 17 December 2004.
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Cite this as:
Algorithms and Theory of Computation Handbook, CRC Press LLC, 1999, "probabilistic Turing machine", in Dictionary of Algorithms and Data Structures [online], Paul E. Black, ed., U.S. National Institute of Standards and Technology. 17 December 2004. (accessed TODAY) Available from: http://www.nist.gov/dads/HTML/probablturng.html