Kolloquium über Mathematische Statistik und Stochastische Prozesse Dr. Martin Wahl Humboldt-Universität zu Berlin 06.12.2016, 16:15 Uhr, Hörsaal 5 Non-asymptotic upper bounds for the reconstruction error of PCA Abstract: Principal component analysis (PCA) is a standard tool for dimension reduction. In this talk, we analyse the reconstruction error of PCA and prove non-asymptotic upper bounds for the corresponding excess risk. These bounds unify and improve several upper bounds from the literature. Moreover, the bounds reveal that the excess risk differs considerably from usually considered subspace distances based on canonical angles. Our approach relies on the analysis of empirical spectral projectors combined with concentration inequalities for empirical covariance operators and empirical eigenvalues. The results are illustrated for covariance matrices satisfying standard eigenvalue decay assumptions. In addition, corresponding bounds for canonical angle distances are discussed. This is joint work with Markus Reiß. Dr. Martin Wahl Humboldt-Universität zu Berlin https://www.mathematik.huberlin.de/de/forschung/forschungsgebiete/stochastik/stoch-employees/martinwahl/ Kontakt: Jun.-Prof. Dr. Mathias Trabs (http://www.math.uni-hamburg.de/home/trabs/) Universität Hamburg
© Copyright 2025 ExpyDoc