arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2103.09411stat.MEecon.EM
收藏

矩阵时间序列的同时解相关

Simultaneous Decorrelation of Matrix Time Series

Yuefeng Han, Rong Chen, Cun-Hui Zhang, Qiwei Yao

摘要:

我们提出了一个同时双线性变换的$p\times q$矩阵时间序列,以减轻建模和预测矩阵时间序列时,$p$和/或$q$大的困难。所得到的变换矩阵假设由几个小矩阵组成的块结构,并且这些小矩阵序列在所有时间上都不相关。因此,通过对这些小矩阵系列中的每一个单独建模而不损失关于线性动态的信息来实现总体简约模型。这样一个简约的模型往往有更好的预测性能,甚至当潜在的真实动态偏离假设的不相关的块结构转换后。估计变换的一致收敛速度的推导,这证明了所提出的双线性变换的一个重要优点,即它是在技术上等价的维数最大的矢量时间序列的解相关$(p,q)$而不是$p\times q$。所提出的方法是通过模拟和真实数据的例子说明数值。

英文摘要:

We propose a contemporaneous bilinear transformation for a $p\times q$ matrix time series to alleviate the difficulties in modeling and forecasting matrix time series when $p$ and/or $q$ are large. The resulting transformed matrix assumes a block structure consisting of several small matrices, and those small matrix series are uncorrelated across all times. Hence an overall parsimonious model is achieved by modelling each of those small matrix series separately without the loss of information on the linear dynamics. Such a parsimonious model often has better forecasting performance, even when the underlying true dynamics deviates from the assumed uncorrelated block structure after transformation. The uniform convergence rates of the estimated transformation are derived, which vindicate an important virtue of the proposed bilinear transformation, i.e. it is technically equivalent to the decorrelation of a vector time series of dimension max$(p,q)$ instead of $p\times q$. The proposed method is illustrated numerically via both simulated and real data examples.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑