# LSAR: Efficient Leverage Score Sampling Algorithm for the Analysis of Big Time Series Data

@article{Eshragh2019LSAREL, title={LSAR: Efficient Leverage Score Sampling Algorithm for the Analysis of Big Time Series Data}, author={Ali Eshragh and Fred Roosta and Asef Nazari and Michael W. Mahoney}, journal={arXiv: Methodology}, year={2019} }

We apply methods from randomized numerical linear algebra (RandNLA) to develop improved algorithms for the analysis of large-scale time series data. We first develop a new fast algorithm to estimate the leverage scores of an autoregressive (AR) model in big data regimes. We show that the accuracy of approximations lies within $(1+\mathcal{O}(\varepsilon))$ of the true leverage scores with high probability. These theoretical results are subsequently exploited to develop an efficient algorithm…

## 7 Citations

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