发表机构
Alpha Benito Research; Department of Mathematics, University of Southern California(Alpha Benito 研究所; 南加州大学数学系)
机构由 AI 辅助整理,请以论文原文为准。AI 中文总结
本文证明稀疏随机张量谱范数的尖锐集中不等式,去除对数因子,并推广至非齐次采样及随机超图模型。
AI 中文摘要
我们证明了具有独立伯努利项的稀疏随机张量谱范数的尖锐集中不等式。设 $T$ 是一个 $k$ 阶张量,维度为 $n\times\cdots\times n$,其元素独立服从伯努利分布 $\mathrm{Bernoulli}(p)$,其中 $k$ 固定。对于任意 $c,r>0$,我们证明当 $np\ge c\log n$ 时,$\\|T-\mathbb E T\\|\le C_{k,r,c}\sqrt{np}$ 以至少 $1-n^{-r}$ 的概率成立。我们将此界推广到具有确定性逐项权重的非齐次伯努利采样。这去除了 Zhou 和 Zhu (2021) 工作中的对数因子。证明采用了 Kahn--Szemerédi 轻-重分解,并对重元组部分进行了精细估计。我们还获得了 Friedman 和 Wigderson (1995) 随机超图模型的免对数第二特征值界。
英文摘要
We prove a sharp concentration inequality for the spectral norm of sparse random tensors with independent Bernoulli entries. Let $T$ be an order-$k$ tensor of dimension $n\times\cdots\times n$ with independent Bernoulli$(p)$ entries, where $k$ is fixed. For any $c,r>0$, we show that $\|T-\mathbb E T\|\le C_{k,r,c}\sqrt{np}$ with probability at least $1-n^{-r}$ whenever $np\ge c\log n$. We extend this bound to inhomogeneous Bernoulli sampling with deterministic entrywise weights. This removes the logarithmic factor in the work of Zhou and Zhu (2021). The proof follows the Kahn--Szemerédi light--heavy decomposition with a refined estimate on the heavy tuple part. We also obtain a log-free second eigenvalue bound for the random hypergraph model of Friedman and Wigderson (1995).
Comments18 pages