Estimating the covariance of random matrices

Pierre Youssef (University of Alberta)

Abstract


We extend to the matrix setting a recent result of Srivastava-Vershynin about estimating the covariance matrix of a random vector. The result can be interpreted as a quantified version of the law of large numbers for  positive semi-definite matrices which verify some regularity assumption. Beside giving examples, we discuss the notion of log-concave matrices and give estimates on the smallest and largest eigenvalues of a sum of such matrices.

Full Text: Download PDF | View PDF online (requires PDF plugin)

Pages: 1-26

Publication Date: December 19, 2013

DOI: 10.1214/EJP.v18-2579

References

  • Adamczak, Radosław; Guédon, Olivier; Latała, Rafał; Litvak, Alexander E.; Oleszkiewicz, Krzysztof; Pajor, Alain; Tomczak-Jaegermann, Nicole. Moment estimates for convex measures. Electron. J. Probab. 17 (2012), no. 101, 19 pp. MR3005719
  • R. Adamczak, A. Litvak, A. Pajor, and N. Tomczak-Jaegermann. Tail estimates for norms of sums of log-concave random vectors. arXiv:1107.4070, July 2011.
  • Adamczak, Radosław; Litvak, Alexander E.; Pajor, Alain; Tomczak-Jaegermann, Nicole. Quantitative estimates of the convergence of the empirical covariance matrix in log-concave ensembles. J. Amer. Math. Soc. 23 (2010), no. 2, 535--561. MR2601042
  • Adamczak, Radosław; Litvak, Alexander E.; Pajor, Alain; Tomczak-Jaegermann, Nicole. Sharp bounds on the rate of convergence of the empirical covariance matrix. C. R. Math. Acad. Sci. Paris 349 (2011), no. 3-4, 195--200. MR2769907
  • Ahlswede, Rudolf; Winter, Andreas. Strong converse for identification via quantum channels. IEEE Trans. Inform. Theory 48 (2002), no. 3, 569--579. MR1889969
  • Aubrun, Guillaume. Sampling convex bodies: a random matrix approach. Proc. Amer. Math. Soc. 135 (2007), no. 5, 1293--1303 (electronic). MR2276637
  • Batson, Joshua D.; Spielman, Daniel A.; Srivastava, Nikhil. Twice-Ramanujan sparsifiers. STOC'09—Proceedings of the 2009 ACM International Symposium on Theory of Computing, 255--262, ACM, New York, 2009. MR2780071
  • Bhatia, Rajendra. Matrix analysis. Graduate Texts in Mathematics, 169. Springer-Verlag, New York, 1997. xii+347 pp. ISBN: 0-387-94846-5 MR1477662
  • Chafaï, Djalil; Guédon, Olivier; Lecué, Guillaume; Pajor, Alain. Interactions between compressed sensing random matrices and high dimensional geometry. Panoramas et Synthèses [Panoramas and Syntheses], 37. Société Mathématique de France, Paris, 2012. 181 pp. ISBN: 978-2-85629-370-6 MR3113826
  • M. De Carli Silva, N. Harvey, and c. Sato. Sparse Sums of Positive Semidefinite Matrices. arXiv:1107.0088v2, July 2011.
  • M. Fradelizi, O. Guédon, and A. Pajor. Spherical thin-shell concentration for convex measures. Available at arXiv:1306.6794.
  • Guédon, Olivier; Milman, Emanuel. Interpolating thin-shell and sharp large-deviation estimates for isotropic log-concave measures. Geom. Funct. Anal. 21 (2011), no. 5, 1043--1068. MR2846382
  • Hoeffding, Wassily. Probability inequalities for sums of bounded random variables. J. Amer. Statist. Assoc. 58 1963 13--30. MR0144363
  • Kannan, Ravi; Lovász, László; Simonovits, Miklós. Random walks and an $O^ *(n^ 5)$ volume algorithm for convex bodies. Random Structures Algorithms 11 (1997), no. 1, 1--50. MR1608200
  • Kolchin, Valentin F.; Sevastʹyanov, Boris A.; Chistyakov, Vladimir P. Random allocations. Translated from the Russian. Translation edited by A. V. Balakrishnan. Scripta Series in Mathematics. V. H. Winston & Sons, Washington, D.C.; distributed by Halsted Press [John Wiley & Sons], New York-Toronto, Ont.-London, 1978. xi+262 pp. ISBN: 0-470-99394-4 MR0471016
  • Lewis, A. S. The convex analysis of unitarily invariant matrix functions. J. Convex Anal. 2 (1995), no. 1-2, 173--183. MR1363368
  • L. Mackey, M. Jordan, R. Chen, B. Farrell, and J. Tropp. Matrix concentration inequalities via the method of exchangeable pairs. Available at arXiv:1201.6002.
  • Oliveira, Roberto Imbuzeiro. Sums of random Hermitian matrices and an inequality by Rudelson. Electron. Commun. Probab. 15 (2010), 203--212. MR2653725
  • Paouris, G. Concentration of mass on convex bodies. Geom. Funct. Anal. 16 (2006), no. 5, 1021--1049. MR2276533
  • Paouris, Grigoris. Small ball probability estimates for log-concave measures. Trans. Amer. Math. Soc. 364 (2012), no. 1, 287--308. MR2833584
  • Rosenthal, Haskell P. On the subspaces of $L^{p}$ $(p>2)$ spanned by sequences of independent random variables. Israel J. Math. 8 1970 273--303. MR0271721
  • Rudelson, M. Random vectors in the isotropic position. J. Funct. Anal. 164 (1999), no. 1, 60--72. MR1694526
  • Srivastava, Nikhil. Spectral sparsification and restricted invertibility. Thesis (Ph.D.)–Yale University. ProQuest LLC, Ann Arbor, MI, 2010. 98 pp. ISBN: 978-1124-09198-3 MR2941475
  • Srivastava, Nikhil; Vershynin, Roman. Covariance estimation for distributions with $2+\varepsilon$ moments. Ann. Probab. 41 (2013), no. 5, 3081--3111. MR3127875
  • Tropp, Joel A. User-friendly tail bounds for sums of random matrices. Found. Comput. Math. 12 (2012), no. 4, 389--434. MR2946459


Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.