Proceedings of the 2021 ACM-SIAM Symposium on Discrete Algorithms (SODA)
Proceedings of the 2021 ACM-SIAM Symposium on Discrete Algorithms (SODA)
复制标题
2021 年 ACM-SIAM 离散算法研讨会 (SODA) 论文集
DOI:
10.1137/1.9781611976465.100
复制
发表时间:
2021
期刊:
影响因子:
--
通讯作者:
Dall'Agnol M
中科院分区:
文献类型:
--
作者:
Dall'Agnol M
We prove a general structural theorem for a wide family of local algorithms, which includes property testers, local decoders, and probabilistically checkable proofs of proximity. Namely, we show that the structure of every algorithm that makesadaptive queries and satisfies a natural robustness condition admits a sample-based algorithm withsample complexity, following the definition of Goldreich and Ron [ACM Trans. Comput. Theory, 8 (2016), 7]. We prove that this transformation is nearly optimal. Our theorem also admits a scheme for constructing privacy-preserving local algorithms. Using the unified view that our structural theorem provides, we obtain results regarding various types of local algorithms, including the following. We strengthen the state-of-the-art lower bound for relaxed locally decodable codes, obtaining anexponentialimprovement on the dependency in query complexity; this resolves an open problem raised by Gur and Lachish [SIAM J. Comput., 50 (2021), pp. 788–813]. We show that any (constant-query) testable property admits a sample-based tester with sublinear sample complexity; this resolves a problem left open in a work of Fischer, Lachish, and Vasudev [Proceedings of the56th Annual Symposium on Foundations of Computer Science, IEEE, 2015, pp. 1163–1182], bypassing an exponential blowup caused by previous techniques in the case of adaptive testers. We prove that the known separation between proofs of proximity and testers is essentially maximal; this resolves a problem left open by Gur and Rothblum [Proceedings of the8th Innovations in Theoretical Computer Science Conference, 2017, pp. 39:1–39:43;Comput. Complexity, 27 (2018), pp. 99–207] regarding sublinear-time delegation of computation. Our techniques strongly rely on relaxed sunflower lemmas and the Hajnal–Szemerédi theorem.