Abstract
The principal component analysis (PCA) is a powerful standard tool for reducing the dimensionality of data. Unfortunately, it is sensitive to outliers so that various robust PCA variants were proposed in the literature. This paper addresses the robust PCA by successively determining the directions of lines having minimal Euclidean distances from the data points. The corresponding energy functional is non-differentiable at a finite number of directions which we call anchor directions. We derive a Weiszfeld-like algorithm for minimizing the energy functional which has several advantages over existing algorithms. Special attention is paid to carefully handling the anchor directions, where the relation between local minima and one-sided derivatives of Lipschitz continuous functions on submanifolds of \(\mathbb {R}^d\) is taken into account. Using ideas for stabilizing the classical Weiszfeld algorithm at anchor points and the Kurdyka–Łojasiewicz property of the energy functional, we prove global convergence of the whole sequence of iterates generated by the algorithm to a critical point of the energy functional. Numerical examples demonstrate the very good performance of our algorithm.
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Attouch, H., Bolte, J., Redont, P., Soubeyran, A.: Proximal alternating minimization and projection methods for nonconvex problems: an approach based on the Kurdyka-Łojasiewicz inequality. Math. Oper. Res. 35(2), 438–457 (2010)
Attouch, H., Bolte, J., Svaiter, B.F.: Convergence of descent methods for semi-algebraic and tame problems: proximal algorithms, forward-backward splitting, and regularized Gauss-Seidel methods. Math. Program. 137(1–2, Ser. A), 91–129 (2013)
Beck, A., Sabach, S.: Weiszfeld’s method: old and new results. J. Optim. Theory Appl. 164(1), 1–40 (2015)
Ben-Tal, A., Zowe, J.: Directional derivatives in nonsmooth optimization. J. Optim. Theory Appl. 47(4), 483–490 (1985)
Candès, E.J., Li, X., Ma, Y., Wright, J.: Robust principal component analysis? J. ACM 58(3), Art. 11 (2011)
Chouzenoux, E., Idier, J., Moussaoui, S.: A majorize-minimize strategy for subspace optimization applied to image restoration. IEEE Trans. Image Process. 20(6), 1517–1528 (2011)
Ding, C., Zhou, D., He, X., Zha, H.: ${R}_1$-PCA: Rotational invariant ${L}_1$-norm principal component analysis for robust subspace factorization. In: Proceedings of the 23rd International Conference on Machine Learning, pp. 281–288. ACM (2006)
Epstein, R., Hallinan, P., Yuille, A.: 5$\pm $2 eigenimages suffice: an empirical investigation of low-dimensional lighting models. In: IEEE Workshop on Physics-Based Vision, pp. 108–116 (1995)
Fischler, M.A., Bolles, R.C.: Random sample consensus: a paradigm for model fitting with applications to image analysis and automated cartography. In: Readings in Computer Vision, pp. 726–740. Elsevier (1987)
Fletcher, P.T., Joshi, S.: Principal geodesic analysis on symmetric spaces: statistics of diffusion tensors. In: Computer Vision and Mathematical Methods in Medical and Biomedical Image Analysis, pp. 87–98. Springer (2004)
Fletcher, P.T., Lu, C., Pizer, S.M., Joshi, S.: Principal geodesic analysis for the study of nonlinear statistics of shape. IEEE Trans. Med. Imaging 23(8), 995–1005 (2004)
Hager, W.W., Phan, D.T., Zhu, J.: Projection algorithms for nonconvex minimization with application to sparse principal component analysis. J. Glob. Optim. 65(4), 657–676 (2016)
Hastie, T., Tibshirani, R., Friedman, J.: The Elements of Statistical Learning: Data Mining, Inference, and Prediction. Springer Series in Statistics. Springer, New York (2001)
Hauberg, S., Feragen, A., Black, M.J.: Grassmann averages for scalable robust PCA. In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, pp. 3810–3817 (2014)
Huber, P.J.: Robust Statistics. Wiley Series in Probability and Mathematical Statistics. Wiley, New York (1981)
Huber, P.J., Ronchetti, E.M.: Robust Statistics, 2nd edn. Wiley Series in Probability and Statistics. Wiley, New York (2009)
Huckemann, S., Ziezold, H.: Principal component analysis for Riemannian manifolds with an application to triangular shape spaces. Adv. Appl. Probab. 38(2), 299–319 (2006)
Katz, I.N.: Local convergence in Fermat’s problem. Math. Program. 6(1), 89–104 (1974)
Ke, Q., Kanade, T.: Robust $\ell _1$ norm factorization in the presence of outliers and missing data by alternative convex programming. In: IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 2005 (CVPR 2005), vol. 1, pp. 739–746. IEEE (2005)
Keeling, S.L., Kunisch, K.: Robust $\ell _1$ approaches to computing the geometric median and principal and independent components. J. Math. Imaging Vis. 56(1), 99–124 (2016)
Kriegel, H.P., Kröger, P., Schubert, E., Zimek, A.: A general framework for increasing the robustness of PCA-based correlation clustering algorithms. In: Scientific and Statistical Database Management. Lecture Notes in Computer Science. 5069, pp. 418–435 (2008)
Kuhn, H.W.: A note on Fermat’s problem. Math. Program. 4, 98–107 (1973)
Kuhn, H.W., Kuenne, R.E.: An efficient algorithm for the numerical solution of the generalized Weber problem in spatial economics. J. Reg. Sci. 4(2), 21–33 (1962)
Kurdyka, K.: On gradients of functions definable in o-minimal structures. Annales de l’Institut Fourier, vol. 48, pp. 769–783 (1998)
Kwak, N.: Principal component analysis based on $\ell _1$-norm maximization. IEEE Trans. Pattern Anal. Mach. Intell. 30(9), 1672–1680 (2008)
Lee, K.-C., Ho, J., Kriegman, D.J.: Acquiring linear subspaces for face recognition under variable lighting. IEEE Trans. Pattern Anal. Mach. Intell. 5, 684–698 (2005)
Lerman, G., Maunu, T.: Fast, robust and non-convex subspace recovery. Inf. Inference 7(2), 277–336 (2017)
Lerman, G., Maunu, T.: An overview of robust subspace recovery. Proc. IEEE 106(8), 1380–1410 (2018)
Lerman, G., Zhang, T.: Robust recovery of multiple subspaces by geometric $l_p$ minimization. Ann. Stat. 39(5), 2686–2715 (2011)
Lerman, G., Zhang, T.: $l_p$-recovery of the most significant subspace among multiple subspaces with outliers. Constr. Approx. 40(3), 329–385 (2014)
Lerman, G., McCoy, M., Tropp, J.A., Zhang, T.: Robust computation of linear models by convex relaxation. Found. Comput. Math. 15(1), 363–410 (2015)
Leroy, A.M., Rousseeuw, P.J.: Robust Regression and Outlier Detection. Wiley Series in Probability and Mathematical Statistics. Wiley, Chichester (1987)
Li, G., Chen, Z.: Projected-pursuit approach to robust dispersion matrices and principal components: Primary theory and Monte-Carlo. J. Am. Stat. Soc. 80, 759–766 (1985)
Li, L., Huang, W., Gu, I.Y.-H., Tian, Q.: Statistical modeling of complex backgrounds for foreground object detection. IEEE Trans. Image Process. 13(11), 1459–1472 (2004)
Łojasiewicz, S.: Une propriété topologique des sous-ensembles analytiques réels. In: Les Équations aux Dérivées Partielles (Paris, 1962), pp. 87–89. Éditions du Centre National de la Recherche Scientifique, Paris (1963)
Luss, R., Teboulle, M.: Conditional gradient algorithms for rank-one matrix approximations with a sparsity constraint. SIAM Rev. 55(1), 65–98 (2013)
Markopoulos, P.P., Karystinos, G.N., Pados, D.A.: Optimal algorithms for $l_1$-subspace signal processing. IEEE Trans. Signal Process. 62(19), 5046–5058 (2014)
Markopoulos, P.P., Kundu, S., Chamadia, S., Pados, D.A.: Efficient l1-norm principal-component analysis via bit flipping. IEEE Trans. Signal Process. 65(16), 4252–4264 (2017)
Maronna, R.A., Martin, R.D., Yohai, V.J.: Robust Statistics: Theory and Methods. Wiley Series in Probability and Statistics. Wiley, Chichester (2006)
Massart, D.L., Kaufman, L., Rousseeuw, P.J., Leroy, A.: Least median of squares: a robust method for outlier and model error detection in regression and calibration. Anal. Chim. Acta 187, 171–179 (1986)
Maunu, T., Zhang, T., Lerman, G.: A well-tempered landscape for non-convex robust subspace recovery (2017). arXiv:1706.03896
McCoy, M., Tropp, J.A.: Two proposals for robust PCA using semidefinite programming. Electron. J. Stat. 5, 1123–1160 (2011)
Mordukhovich, B., Nam, N.M., Yen, N.D.: Fréchet subdifferential calculus and optimality conditions in nondifferentiable programming. Optimization 55(5–6), 685–708 (2006)
Neumayer, S., Nimmer, M., Steidl, G., Stephani, H.: On a projected Weiszfeld algorithm. In: Lauze, F., Dong, Y., Dahl, A.B. (eds.) Scale Space and Variational Methods in Computer Vision. Lecture Notes in Computer Science, vol. 10302, pp. 486–497. Springer, New York (2017)
Neumayer, S., Nimmer, M., Setzer, S., Steidl, G.: On the rotational invariant ${L}_1$-norm PCA (2019). http://arxiv.org/pdf/1902.03840v1
Nie, F., Huang, H., Ding, C., Luo, D., Wang, H.: Robust principal component analysis with non-greedy $\ell _1$-norm maximization. In: IJCAI Proceedings-International Joint Conference on Artificial Intelligence, vol. 22, pp. 1433 (2011)
Ostresh Jr., L.M.: On the convergence of a class of iterative methods for solving the Weber location problem. Oper. Res. 26(4), 597–609 (1978)
Pearson, K.: On lines and planes of closest fit to systems of points in space. Philos. Mag. 2(11), 559–572 (1901)
Pennec, X.: Barycentric subspace analysis on manifolds (2016). arXiv:1607.02833
Pennec, X.: Sample-limited $l_p$ barycentric subspace analysis on constant curvature spaces. In: International Conference on Geometric Science of Information, pp. 20–28. Springer (2017)
Podosinnikova, A., Setzer, S., Hein, M.: Robust PCA: Optimization of the robust reconstruction error over the Stiefel manifold. In: German Conference on Pattern Recognition, pp. 121–131. Springer (2014)
Rockafellar, R.T.: Convex Analysis. Princeton University Press, Princeton (1970)
Rousseeuw, P.J., Leroy, A.M.: Robust Regression and Outlier Detection. Wiley Series in Probability and Mathematical Statistics: Applied Probability and Statistics. Wiley, New York (1987)
Schneck, G.: Robust principal component analysis. Bachelor Thesis, TU Kaiserslautern (2018)
Setzer, S., Steidl, G., Teuber, T.: On vector and matrix median computation. J. Comput. Appl. Math. 236(8), 2200–2222 (2012)
Sommer, S., Lauze, F., Nielsen, M.: Optimization over geodesics for exact principal component analysis. Adv. Comput. Math. 40, 283–313 (2014)
Vardi, Y., Zhang, C.H.: A modified Weiszfeld algorithm for the Fermat-Weber location. Math. Program. 90, 559–566 (2001)
Vazsonyi, A.: Pure mathematics and Weiszfeld algorithm. Decis. Line 33(3), 12–13 (2002)
Weiszfeld, E.: Sur le point pour lequel les sommes des distances de $n$ points donnés et minimum. Tôhoku Math. J. 43, 355–386 (1937)
Xu, H., Caramanis, C., Sanghavi, S.: Robust PCA via outlier pursuit. IEEE Trans. Inf. Theory 58(3), 3047–3064 (2012)
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Funding by the German Research Foundation (DFG) within the Research Training Group 1932, project area P3, is gratefully acknowledged.
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Appendix A: One-Sided Derivatives and Minimizers on Embedded Manifolds
Appendix A: One-Sided Derivatives and Minimizers on Embedded Manifolds
The one-sided directional derivative of a function \(f:\mathbb {R}^d \rightarrow \mathbb {R}\), \(d \in {\mathbb {N}}\), at a point \(x \in \mathbb {R}^d\) in direction \(h \in \mathbb {R}^d\) is defined by
Restricting f to a submanifold \({\mathcal {M}} \subseteq \mathbb {R}^d\), we can restrict our considerations to \(h \in T_x {\mathcal {M}}\). Recall that \({\mathcal {M}} \subseteq \mathbb {R}^d\) is an m-dimensional submanifold of \(\mathbb {R}^d\) if for each point \(x \in {\mathcal {M}}\) there exists an open neighborhood \(U \subseteq \mathbb {R}^d\) as well as an open set \(\Omega \subseteq \mathbb {R}^m\) and a so-called parametrization \(\varphi \in C^1(\Omega , \mathbb {R}^d)\) of \({\mathcal {M}}\) with the properties
-
(i)
\(\varphi (\Omega ) = {\mathcal {M}} \cap U\),
-
(ii)
\(\varphi ^{-1}:{\mathcal {M}} \cap U \rightarrow \Omega \) is surjective and continuous, and
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(iii)
\(D \varphi (x)\) has full rank m for all \(x \in \Omega \).
To establish the relation between one-sided directional derivatives and local minima of functions on manifolds we need the following lemma. A proof can be found in [45, Lemma B.1].
Lemma A.1
Let \({\mathcal {M}}\subset \mathbb {R}^{d}\) be an m-dimensional submanifold of \(\mathbb {R}^{d}\). Then the tangent space \(T_{x}{\mathcal {M}}\) and the tangent cone
coincide.
The following theorem gives a general necessary and sufficient condition for local minimizers of Lipschitz continuous functions on embedded manifolds using the notation of one-sided derivatives. For the Euclidean setting \({\mathcal {M}} = \mathbb {R}^d\), the first relation of the proposition is trivially fulfilled for any function \(f:\mathbb {R}^d \rightarrow \mathbb {R}\), while a proof of the sufficient minimality condition in the second part was given in [4]. Moreover, the authors of [4] gave an example that Lipschitz continuity in the second part cannot be weakened to just continuity.
Theorem A.2
Let \({\mathcal {M}} \subset \mathbb {R}^d\) be an m-dimensional submanifold of \(\mathbb {R}^d\) and \(f:\mathbb {R}^d \rightarrow \mathbb {R}\) a locally Lipschitz continuous function. Then the following holds true:
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1.
If \({\hat{x}} \in {\mathcal {M}}\) is a local minimizer of f on \({\mathcal {M}}\), then \(Df({\hat{x}};h) \ge 0\) for all \(h \in T_{{\hat{x}}}{\mathcal {M}}\).
-
2.
If \(Df({\hat{x}};h) >0\) for all \(h\in T_{{\hat{x}}} {\mathcal {M}} \setminus \{0\}\), then \({\hat{x}}\) is a strict local minimizer of f on \({\mathcal {M}}\).
A proof can be found in [45, Thm. 6.1] along with an example which demonstrates the necessity of the Lipschitz continuity of f in the manifold setting in the first part of the theorem. Furthermore, note that \(Df({\hat{x}};h) \ge 0\) for all \(h\in T_{{\hat{x}}} {\mathcal {M}} \setminus \{0\}\) does not imply that \({\hat{x}}\) is a local minimizer of f on \({\mathcal {M}}\).
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Neumayer, S., Nimmer, M., Setzer, S. et al. On the Robust PCA and Weiszfeld’s Algorithm. Appl Math Optim 82, 1017–1048 (2020). https://doi.org/10.1007/s00245-019-09566-1
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DOI: https://doi.org/10.1007/s00245-019-09566-1