arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1603.06313cs.ITmath.ITmath.OCstat.ML
收藏

带扩张子的凸块稀疏线性回归--可证

Convex block-sparse linear regression with expanders -- provably

Anastasios Kyrillidis, Bubacarr Bah, Rouzbeh Hasheminezhad, Quoc Tran-Dinh, Luca Baldassarre, Volkan Cevher

摘要:

稀疏矩阵是机器学习和优化的研究对象。当使用这样的矩阵时,代替密集矩阵,优化中的总体复杂性要求在实践中可以在空间和运行时间方面显著降低。基于这一观察,我们研究了一个凸优化方案,用于从线性测量中恢复块稀疏。为了获得线性草图,我们使用扩展矩阵,即,稀疏矩阵,每列仅包含少数非零值。然而,据我们所知,这种算法的解决方案只从非凸的角度进行了研究。我们的目的是在理论上描述这种设置下的凸方法的性能。我们的主要新颖之处是恢复错误的表达在基于模型的规范,同时确保解决方案的生活在模型中。为了实现这一点,我们证明了基于模型的稀疏矩阵满足零空间属性的群版本。我们在合成和实际应用中的实验结果支持我们在凸设置中更快恢复的主张-而不是使用密集的传感矩阵,同时显示出有竞争力的恢复性能。

英文摘要:

Sparse matrices are favorable objects in machine learning and optimization. When such matrices are used, in place of dense ones, the overall complexity requirements in optimization can be significantly reduced in practice, both in terms of space and run-time. Prompted by this observation, we study a convex optimization scheme for block-sparse recovery from linear measurements. To obtain linear sketches, we use expander matrices, i.e., sparse matrices containing only few non-zeros per column. Hitherto, to the best of our knowledge, such algorithmic solutions have been only studied from a non-convex perspective. Our aim here is to theoretically characterize the performance of convex approaches under such setting. Our key novelty is the expression of the recovery error in terms of the model-based norm, while assuring that solution lives in the model. To achieve this, we show that sparse model-based matrices satisfy a group version of the null-space property. Our experimental findings on synthetic and real applications support our claims for faster recovery in the convex setting -- as opposed to using dense sensing matrices, while showing a competitive recovery performance.

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。

↑