skip to main content
research-article

Non-stationary First-Order Primal-Dual Algorithms with Faster Convergence Rates

Published: 01 January 2020 Publication History

Abstract

In this paper, we propose two novel non-stationary first-order primal-dual algorithms to solve non-smooth composite convex optimization problems. Unlike existing primal-dual schemes where the parameters are often fixed, our methods use predefined and dynamic sequences for parameters. We prove that our first algorithm can achieve an $\mathcal{O}\left(1/k\right)$ convergence rate on the primal-dual gap, and primal and dual objective residuals, where $k$ is the iteration counter. Our rate is on the non-ergodic (i.e., the last iterate) sequence of the primal problem and on the ergodic (i.e., the averaging) sequence of the dual problem, which we call the semi-ergodic rate. By modifying the step-size update rule, this rate can be boosted even faster on the primal objective residual. When the problem is strongly convex, we develop a second primal-dual algorithm that exhibits an $\mathcal{O}\left(1/k^2\right)$ convergence rate on the same three types of guarantees. Again by modifying the step-size update rule, this rate becomes faster on the primal objective residual. Our primal-dual algorithms are the first ones to achieve such fast convergence rate guarantees under mild assumptions compared to existing works, to the best of our knowledge. As byproducts, we apply our algorithms to solve constrained convex optimization problems and prove the same convergence rates on both the objective residuals and the feasibility violation. We still obtain at least $\mathcal{O}\left(1/k^2\right)$ rates even when the problem is “semi-strongly” convex. We verify our theoretical results via two well-known numerical examples.

References

[1]
H. Attouch and J. Peypouquet, The rate of convergence of Nesterov's accelerated forward-backward method is actually faster than $1/k^2$, SIAM J. Optim., 26 (2016), pp. 1824--1834, https://doi.org/10.1137/15M1046095.
[2]
H. H. Bauschke and P. Combettes, Convex Analysis and Monotone Operator Theory in Hilbert Spaces, 2nd ed., Springer-Verlag, Cham, 2017.
[3]
A. Beck and M. Teboulle, A fast iterative shrinkage-thresholding algorithm for linear inverse problems, SIAM J. Imaging Sci., 2 (2009), pp. 183--202, https://doi.org/10.1137/080716542.
[4]
R. Boţ, E. R. Csetnek, and A. Heinrich, A primal-dual splitting algorithm for finding zeros of sums of maximally monotone operators, SIAM J. Optim., 23 (2013), pp. 2011--2036, https://doi.org/10.1137/12088255X.
[5]
R. Boţ, E. Csetnek, A. Heinrich, and C. Hendrich, On the convergence rate improvement of a primal-dual splitting algorithm for solving monotone inclusion problems, Math. Program., 150 (2015), pp. 251--279.
[6]
R. I. Boţ and C. Hendrich, Convergence analysis for a primal-dual monotone + skew splitting algorithm with applications to total variation minimization, J. Math. Imaging Vis., 49 (2014), pp. 551--568.
[7]
S. Boyd, N. Parikh, E. Chu, B. Peleato, and J. Eckstein, Distributed optimization and statistical learning via the alternating direction method of multipliers, Found. Trends Mach. Learn., 3 (2011), pp. 1--122.
[8]
L. M. Bricen͂o-Arias and P. L. Combettes, A monotone + skew splitting model for composite monotone inclusions in duality, SIAM J. Optim., 21 (2011), pp. 1230--1250, https://doi.org/10.1137/10081602X.
[9]
A. Chambolle, M. J. Ehrhardt, P. Richtárik, and C.-B. Schönlieb, Stochastic primal-dual hybrid gradient algorithm with arbitrary sampling and imaging applications, SIAM J. Optim., 28 (2018), pp. 2783--2808, https://doi.org/10.1137/17M1134834.
[10]
A. Chambolle and T. Pock, A first-order primal-dual algorithm for convex problems with applications to imaging, J. Math. Imaging Vis., 40 (2011), pp. 120--145.
[11]
A. Chambolle and T. Pock, An introduction to continuous optimization for imaging, Acta Numer., 25 (2016), pp. 161--319.
[12]
A. Chambolle and T. Pock, On the ergodic convergence rates of a first-order primal--dual algorithm, Math. Program., 159 (2016), pp. 253--287.
[13]
P. Chen, J. Huang, and X. Zhang, A primal-dual fixed point algorithm for minimization of the sum of three convex separable functions, Fixed Point Theory Appl., 2016 (2016), 54.
[14]
Y. Chen, G. Lan, and Y. Ouyang, Optimal primal-dual methods for a class of saddle-point problems, SIAM J. Optim., 24 (2014), pp. 1779--1814, https://doi.org/10.1137/130919362.
[15]
P. L. Combettes and J.-C. Pesquet, Proximal splitting methods in signal processing, in Fixed-Point Algorithms for Inverse Problems in Science and Engineering, Springer, New York, 2011, pp. 185--212.
[16]
P. L. Combettes and V. R. Wajs, Signal recovery by proximal forward-backward splitting, Multiscale Model. Simul., 4 (2005), pp. 1168--1200, https://doi.org/10.1137/050626090.
[17]
P. L. Combettes and J.-C. Pesquet, Primal-dual splitting algorithm for solving inclusions with mixtures of composite, Lipschitzian, and parallel-sum type monotone operators, Set-Valued Var. Anal., 20 (2012), pp. 307--330.
[18]
L. Condat, A primal-dual splitting method for convex optimization involving Lipschitzian, proximable and linear composite terms, J. Optim. Theory Appl., 158 (2013), pp. 460--479.
[19]
D. Davis, Convergence rate analysis of primal-dual splitting schemes, SIAM J. Optim., 25 (2015), pp. 1912--1943, https://doi.org/10.1137/151003076.
[20]
D. Davis, Convergence rate analysis of the forward-Douglas--Rachford splitting scheme, SIAM J. Optim., 25 (2015), pp. 1760--1786, https://doi.org/10.1137/140992291.
[21]
D. Davis and W. Yin, Convergence rate analysis of several splitting schemes, in Splitting Methods in Communication, Imaging, Science, and Engineering, R. Glowinski, S. J. Osher, and W. Yin, eds., Springer, New York, 2016, pp. 115--163.
[22]
D. Davis and W. Yin, Faster convergence rates of relaxed Peaceman-Rachford and ADMM under regularity assumptions, Math. Oper. Res., 42 (2017), pp. 577--896.
[23]
D. Davis and W. Yin, A three-operator splitting scheme and its optimization applications, Set-Valued Var. Anal., 25 (2017), pp. 829--858.
[24]
C. Dünner, S. Forte, M. Takáč, and M. Jaggi, Primal-dual rates and certificates, in Proceedings of the 33rd International Conference on Machine Learning (ICML), New York, NY, 2016, pp. 783--792.
[25]
J. Eckstein and D. Bertsekas, On the Douglas-Rachford splitting method and the proximal point algorithm for maximal monotone operators, Math. Program., 55 (1992), pp. 293--318.
[26]
E. Esser, X. Zhang, and T. F. Chan, A general framework for a class of first order primal-dual algorithms for convex optimization in imaging science, SIAM J. Imaging Sci., 3 (2010), pp. 1015--1046, https://doi.org/10.1137/09076934X.
[27]
J. E. Esser, Primal-dual algorithm for convex models and applications to image restoration, registration and nonlocal inpainting, Ph.D. thesis, University of California, Los Angeles, Los Angeles, CA, 2010.
[28]
F. Facchinei and J.-S. Pang, Finite-Dimensional Variational Inequalities and Complementarity Problems, Vol. 1--2, Springer-Verlag, New York, 2003.
[29]
R. Glowinski, S. Osher, and W. Yin, Splitting Methods in Communication, Imaging, Science, and Engineering, Springer, New York, 2017.
[30]
T. Goldstein, M. Li, and X. Yuan, Adaptive primal-dual splitting methods for statistical learning and image processing, in Advances in Neural Information Processing Systems (Montreal, Canada, 2015), NeurIPS, San Diego, CA, 2015, pp. 2080--2088.
[31]
T. Goldstein, B. O'Donoghue, S. Setzer, and R. Baraniuk, Fast alternating direction optimization methods, SIAM J. Imaging Sci., 7 (2014), pp. 1588--1623, https://doi.org/10.1137/120896219.
[32]
E. Y. Hamedani and N. S. Aybat, A Primal-Dual Algorithm for General Convex-Concave Saddle Point Problems, preprint, https://arxiv.org/abs/1803.01401, 2018.
[33]
B. He and X. Yuan, Convergence analysis of primal-dual algorithms for saddle-point problem: From contraction perspective, SIAM J. Imaging Sci., 5 (2012), pp. 119--149, https://doi.org/10.1137/100814494.
[34]
Y. He and R. D. C. Monteiro, An accelerated HPE-type algorithm for a class of composite convex-concave saddle-point problems, SIAM J. Optim., 26 (2016), pp. 29--56, https://doi.org/10.1137/14096757X.
[35]
L. T. K. Hien, R. Zhao, and W. B. Haskell, An Inexact Primal-Dual Smoothing Framework for Large-Scale Non-Bilinear Saddle Point Problems, preprint, https://arxiv.org/abs/1711.03669, 2017.
[36]
H. Li and Z. Lin, Accelerated alternating direction method of multipliers: An optimal $\mathcal{O}(1/k)$ nonergodic analysis, J. Sci. Comput., 79 (2019), pp. 671--699.
[37]
J. Liang, J. Fadili, and G. Peyré, Local convergence properties of Douglas--Rachford and alternating direction method of multipliers, J. Optim. Theory Appl., 172 (2017), pp. 874--913.
[38]
P. L. Lions and B. Mercier, Splitting algorithms for the sum of two nonlinear operators, SIAM J. Numer. Anal., 16 (1979), pp. 964--979, https://doi.org/10.1137/0716071.
[39]
Y. Malitsky and T. Pock, A first-order primal-dual algorithm with linesearch, SIAM J. Optim., 28 (2018), pp. 411--432, https://doi.org/10.1137/16M1092015.
[40]
R. D. C. Monteiro and B. F. Svaiter, On the complexity of the hybrid proximal extragradient method for the iterates and the ergodic mean, SIAM J. Optim., 20 (2010), pp. 2755--2787, https://doi.org/10.1137/090753127.
[41]
R. D. C. Monteiro and B. F. Svaiter, Complexity of variants of Tseng's modified F-B splitting and Korpelevich's methods for hemivariational inequalities with applications to saddle-point and convex optimization problems, SIAM J. Optim., 21 (2011), pp. 1688--1720, https://doi.org/10.1137/100801652.
[42]
R. D. C. Monteiro and B. F. Svaiter, Iteration-complexity of block-decomposition algorithms and the alternating direction method of multipliers, SIAM J. Optim., 23 (2013), pp. 475--507, https://doi.org/10.1137/110849468.
[43]
MOSEK-ApS, The MOSEK Optimization Toolbox for MATLAB Manual, Version \textup9.0, 2019, http://docs.mosek.com/9.0/toolbox/index.html.
[44]
I. Necoara and A. Patrascu, Iteration complexity analysis of dual first-order methods for conic convex programming, Optim. Methods Softw., 31 (2016), pp. 645--678.
[45]
I. Necoara, A. Patrascu, and F. Glineur, Complexity of first-order inexact Lagrangian and penalty methods for conic convex programming, Optim. Methods Softw., 34 (2019), pp. 305--335.
[46]
A. Nemirovski, Prox-method with rate of convergence $\mathcal{O}(1/t)$ for variational inequalities with Lipschitz continuous monotone operators and smooth convex-concave saddle point problems, SIAM J. Optim, 15 (2004), pp. 229--251, https://doi.org/10.1137/S1052623403425629.
[47]
Y. Nesterov, A method for unconstrained convex minimization problem with the rate of convergence $\mathcal{O}(1/k^2)$, Dokl. Akad. Nauk. USSR, 269 (1983), pp. 543--547.
[48]
Y. Nesterov, Excessive gap technique in nonsmooth convex minimization, SIAM J. Optim., 16 (2005), pp. 235--249, https://doi.org/10.1137/S1052623403422285.
[49]
Y. Nesterov, Smooth minimization of non-smooth functions, Math. Program., 103 (2005), pp. 127--152.
[50]
D. O'Connor and L. Vandenberghe, Primal-dual decomposition by operator splitting and applications to image deblurring, SIAM J. Imaging Sci., 7 (2014), pp. 1724--1754, https://doi.org/10.1137/13094671X.
[51]
D. O'Connor and L. Vandenberghe, On the equivalence of the primal-dual hybrid gradient method and Douglas-Rachford splitting, Math. Program., 179 (2020), pp. 85--108.
[52]
Y. Ouyang, Y. Chen, G. Lan, and E. Pasiliao, Jr., An accelerated linearized alternating direction method of multipliers, SIAM J. Imaging Sci., 8 (2015), pp. 644--681, https://doi.org/10.1137/14095697X.
[53]
T. Pock, D. Cremers, H. Bischof, and A. Chambolle, An algorithm for minimizing the Mumford-Shah functional, in Proceedings of the 12th IEEE International Conference on Computer Vision, IEEE, Washington, DC, 2009, pp. 1133--1140.
[54]
J. E. Spingarn, Partial inverse of a monotone operator, Appl. Math. Optim., 10 (1983), pp. 247--265.
[55]
Q. Tran-Dinh, Proximal alternating penalty algorithms for constrained convex optimization, Comput. Optim. Appl., 72 (2019), pp. 1--43.
[56]
Q. Tran-Dinh, A. Alacaoglu, O. Fercoq, and V. Cevher, An adaptive primal-dual framework for nonsmooth convex minimization, Math. Program. Comput. 12 (2020), pp. 451--491.
[57]
Q. Tran-Dinh, O. Fercoq, and V. Cevher, A smooth primal-dual optimization framework for nonsmooth composite convex minimization, SIAM J. Optim., 28 (2018), pp. 96--134, https://doi.org/10.1137/16M1093094.
[58]
Q. Tran-Dinh, C. Savorgnan, and M. Diehl, Combining Lagrangian decomposition and excessive gap smoothing technique for solving large-scale separable convex optimization problems, Compt. Optim. Appl., 55 (2013), pp. 75--111.
[59]
P. Tseng, Further applications of a splitting algorithm to decomposition in variational inequalities and convex programming, Math. Program., 48 (1990), pp. 249--263.
[60]
P. Tseng, On accelerated proximal gradient methods for convex-concave optimization, SIAM J. Optim., submitted (2008).
[61]
T. Valkonen, Inertial, corrected, primal--dual proximal splitting, SIAM J. Optim., 30 (2020), pp. 1391--1420.
[62]
C. B. Vu, A splitting algorithm for dual monotone inclusions involving co-coercive operators, Adv. Comput. Math., 38 (2013), pp. 667--681.
[63]
B. E. Woodworth and N. Srebro, Tight complexity bounds for optimizing composite objectives, in Advances in Neural Information Processing Systems (NIPS) (Barcelona, Spain, 2016), NeurIPS, San Diego, CA, 2016, pp. 3639--3647.
[64]
Y. Xu, Accelerated first-order primal-dual proximal methods for linearly constrained composite convex programming, SIAM J. Optim., 27 (2017), pp. 1459--1484, https://doi.org/10.1137/16M1082305.
[65]
M. Yan, A new primal-dual algorithm for minimizing the sum of three functions with a linear operator, J. Sci. Comput., 76 (2018), pp. 1698--1717.
[66]
W. Yin, S. Osher, D. Goldfarb, and J. Darbon, Bregman iterative algorithms for $\ell_{\textup{1}}$-minimization with applications to compressed sensing, SIAM J. Imaging Sci., 1 (2008), pp. 143--168, https://doi.org/10.1137/070703983.
[67]
X. Zhang, M. Burger, and S. Osher, A unified primal-dual algorithm framework based on Bregman iteration, J. Sci. Comput., 46 (2011), pp. 20--46.
[68]
M. Zhu and T. Chan, An Efficient Primal-Dual Hybrid Gradient Algorithm for Total Variation Image Restoration, UCLA CAM Technical Report 08--34, UCLA, Los Angeles, CA, 2008.

Cited By

View all

Recommendations

Comments

Information & Contributors

Information

Published In

cover image SIAM Journal on Optimization
SIAM Journal on Optimization  Volume 30, Issue 4
2020
687 pages
ISSN:1052-6234
DOI:10.1137/sjope8.30.4
Issue’s Table of Contents

Publisher

Society for Industrial and Applied Mathematics

United States

Publication History

Published: 01 January 2020

Author Tags

  1. non-stationary primal-dual method
  2. non-ergodic convergence rate
  3. fast convergence rates
  4. composite convex minimization
  5. constrained convex optimization

Author Tags

  1. 90C25
  2. 90C06
  3. 90-08

Qualifiers

  • Research-article

Contributors

Other Metrics

Bibliometrics & Citations

Bibliometrics

Article Metrics

  • Downloads (Last 12 months)0
  • Downloads (Last 6 weeks)0
Reflects downloads up to 14 Jan 2025

Other Metrics

Citations

Cited By

View all

View Options

View options

Media

Figures

Other

Tables

Share

Share

Share this Publication link

Share on social media