arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1806.01455stat.MLcs.LGcs.SI
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EigenNetworks

EigenNetworks

Carnegie Mellon University(卡内基梅隆大学);Visby(维斯比)

Jonathan Mei, José M. F. Moura

摘要:

许多应用程序没有物理定律的好处,无法为观测数据导出简洁的描述性模型。在替代方案中,$N$时间序列$\{ x_{nk}, k>0 \}_{n=1}^{N}$之间的相互依赖性如今通常由实际上可能非常大的图或网络$G$捕获。网络本身也可以随时间改变(即,作为$G_k$)。跟踪时变网络的变化带来了重大挑战,包括相关的计算问题。此外,大量的网络可能无法进行有用的分析。本文将时变网络$\left\{G_k\right\}$近似为特征网络的加权线性组合。本征网络是固定的构建块,其通过首先从数据$\{ x_{nk}, k>0 \}_{n=1}^{N}$学习图的时间序列$G_k$,然后进行主网络分析过程来估计。本征网络表示的权重是本征特征,并且时变网络$\left\{G_k\right\}$描述本征网络空间中的轨迹。这些本征轨迹应该是平滑的,因为网络$G_k$的变化速率比数据$x_{nk}$慢得多,除非发生结构性网络移位,这可能反映了底层应用和数据源的突然变化。算法学习的时间序列的图$\left\{G_k\right\}$,推导出的特征网络,特征和特征轨迹,并检测变点。模拟数据和两个实时时间序列数据(美国参议院的投票记录和基因表达数据的\textit{Drosophila Melanogaster},因为它经历了它的生命周期)的实验证明了学习的性能,并提供有趣的解释的特征网络。

英文摘要:

Many applications donot have the benefit of the laws of physics to derive succinct descriptive models for observed data. In alternative, interdependencies among $N$ time series $\{ x_{nk}, k>0 \}_{n=1}^{N}$ are nowadays often captured by a graph or network $G$ that in practice may be very large. The network itself may change over time as well (i.e., as $G_k$). Tracking brute force the changes of time varying networks presents major challenges, including the associated computational problems. Further, a large set of networks may not lend itself to useful analysis. This paper approximates the time varying networks $\left\{G_k\right\}$ as weighted linear combinations of eigennetworks. The eigennetworks are fixed building blocks that are estimated by first learning the time series of graphs $G_k$ from the data $\{ x_{nk}, k>0 \}_{n=1}^{N}$, followed by a Principal Network Analysis procedure. The weights of the eigennetwork representation are eigenfeatures and the time varying networks $\left\{G_k\right\}$ describe a trajectory in eigennetwork space. These eigentrajectories should be smooth since the networks $G_k$ vary at a much slower rate than the data $x_{nk}$, except when structural network shifts occur reflecting potentially an abrupt change in the underlying application and sources of the data. Algorithms for learning the time series of graphs $\left\{G_k\right\}$, deriving the eigennetworks, eigenfeatures and eigentrajectories, and detecting changepoints are presented. Experiments on simulated data and with two real time series data (a voting record of the US senate and genetic expression data for the \textit{Drosophila Melanogaster} as it goes through its life cycle) demonstrate the performance of the learning and provide interesting interpretations of the eigennetworks.

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。

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