# Tree-Size Bounded Alternation

@article{Ruzzo1980TreeSizeBA, title={Tree-Size Bounded Alternation}, author={W. L. Ruzzo}, journal={J. Comput. Syst. Sci.}, year={1980}, volume={21}, pages={218-235} }

The size of an accepting computation tree of an alternating Turing machine (ATM) is introduced as a complexity measure. We present a number of applications of tree-size to the study of more traditional complexity classes. Tree-size on ATMs is shown to closely correspond to time on nondeterministic TMs and on nondeterministic auxiliary pushdown automata. One application of the later is a useful new characterization of the class of languages log-space-reducible to context-free languages… Expand

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