# On the Structure of Logspace Probabilistic Complexity Classes

@article{Macarie1999OnTS, title={On the Structure of Logspace Probabilistic Complexity Classes}, author={Ioan I. Macarie}, journal={SIAM J. Comput.}, year={1999}, volume={29}, pages={987-1007} }

We investigate hierarchical properties and logspace reductions of languages recognized by logspace probabilistic Turing machines, Arthur--Merlin games, and games against nature with logspace probabilistic verifiers. Each logspace complexity class is decomposed into a hierarchy based on corresponding two-way multihead finite-state automata and we (eventually) prove the separation of the hierarchy levels (even for languages over a single-letter alphabet); furthermore, we show efficient reductions…

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