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arXiv · 2304.01438

Tight Space Lower Bound for Pseudo-Deterministic Approximate Counting

Ofer Grossman·Meghal Gupta·Mark Sellke
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Abstract

We investigate one of the most basic problems in streaming algorithms: approximating the number of elements in the stream. In 1978, Morris famously gave a randomized algorithm achieving a constant-factor approximation error for streams of length at most N in space $O(\log \log N)$. We investigate the pseudo-deterministic complexity of the problem and prove a tight $\Omega(\log N)$ lower bound, thus resolving a problem of Goldwasser-Grossman-Mohanty-Woodruff.

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Ofer Grossman, Meghal Gupta, Mark Sellke. 2023-04-04. Tight Space Lower Bound for Pseudo-Deterministic Approximate Counting. https://doi.org/10.1109/focs57990.2023.00091

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