We derive so-called weak and strong \textit{max-laws of large numbers} for $% \max_{1\leq i\leq k_{n}}|1/n\sum_{t=1}^{n}x_{i,n,t}|$ for zero mean stochastic triangular arrays $\{x_{i,n,t}$ $:$ $1$ $\leq $ $t$ $\leq n\}_{n\geq 1}$, with dimension counter $i$ $=$ $1,...,k_{n}$ and dimension $% k_{n}$ $\rightarrow $ $\infty $. Rates of convergence are also analyzed based on feasible sequences $\{k_{n}\}$. We work in three dependence settings: independence, Dedecker and Prieur's (2004) $\tau $-mixing and Wu's (2005) physical dependence. We initially ignore cross-coordinate $i$ dependence as a benchmark. We then work with martingale, nearly martingale, and mixing coordinates to deliver improved bounds on $k_{n}$. Finally, we use the results in three applications, each representing a key novelty: we ($i$) bound $k_{n}$\ for a max-correlation statistic for regression residuals under $\alpha $-mixing or physical dependence; ($ii$) extend correlation screening, or marginal regressions, to physical dependent data with diverging dimension $k_{n}$ $\rightarrow $ $\infty $; and ($iii$) test a high dimensional parameter after partialling out a fixed dimensional nuisance parameter in a linear time series regression model under $\tau $% -mixing.
翻译:本文针对零均值随机三角数组 $\{x_{i,n,t}$ $:$ $1$ $\leq $ $t$ $\leq n\}_{n\geq 1}$,推导了统计量 $% \max_{1\leq i\leq k_{n}}|1/n\sum_{t=1}^{n}x_{i,n,t}|$ 的所谓弱与强\textit{极大值大数定律},其中维度指标 $i$ $=$ $1,...,k_{n}$,且维度 $% k_{n}$ $\rightarrow $ $\infty $。我们还基于可行序列 $\{k_{n}\}$ 分析了收敛速率。我们在三种相依性设定下展开研究:独立性、Dedecker 与 Prieur (2004) 的 $\tau $-混合以及 Wu (2005) 的物理相依性。我们首先忽略坐标间(即 $i$ 间)的相依性作为基准情形。随后,我们针对鞅、近似鞅以及混合坐标进行研究,以给出关于 $k_{n}$ 的改进界。最后,我们将所得结果应用于三个场景,每个应用均代表一项核心创新:我们 ($i$) 在 $\alpha $-混合或物理相依条件下,为回归残差的最大相关统计量给出了 $k_{n}$ 的界;($ii$) 将相关性筛选(或称边际回归)推广至具有发散维度 $k_{n}$ $\rightarrow $ $\infty $ 的物理相依数据;以及 ($iii$) 在 $\tau $-混合条件下,对线性时间序列回归模型中剔除了固定维数冗余参数后的高维参数进行检验。