Abstract
In this paper, a new nonsmooth trust region algorithm is proposed for solving unconstrained minimization problems with locally Lipschitz objective functions. At first, by using an approximation of the steepest descent direction, a local model is presented for locally Lipschitz functions. More precisely, in the quadratic model of classical trust region methods, the gradient vector is replaced by an approximation of the steepest descent direction. We then apply one of the efficient approaches of classical trust region methods in order to solve the obtained model. Using the BFGS updating formula for the Hessian approximation of the model, we show that the proposed algorithm is convergent under some mild and standard conditions on the objective function. Finally, the presented algorithm is implemented in the MATLAB environment and applied on some nonsmooth test problems.
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References
Shor, N.Z.: Minimization Methods for Non-differentiable Functions. Springer, Berlin (1985)
Frangioni, A.: Generalized bundle methods. SIAM J. Optim. 13, 117–156 (2003)
Makela, M.: Survey of bundle methods for nonsmooth optimization. Optim. Methods Softw. 17(1), 1–29 (2002)
Hiriart-Urruty, J.B., Lemaréchal, C.: Convex Analysis and Minimization Algorithms II: Advanced Theory and Bundle Methods. Springer, Berlin (1993)
Schramm, H., Zowe, J.: A version of the bundle idea for minimizing a nonsmooth function: conceptual idea, convergence analysis, numerical results. SIAM J. Optim. 2, 121–152 (1992)
Polak, E., Royset, J.: Algorithms for finite and semi-infinite minmaxmin problems using adaptive smoothing techniques. J. Optim. Theory Appl. 119(3), 421–457 (2003)
Bagirov, A.M.: Continuous subdifferential approximations and their applications. J. Math. Sci. 115, 2567–2609 (2003)
Lukan, L., Vlcek, J.: A bundle-newton method for nonsmooth unconstrained minimization. Math. Program. 83(1), 373–391 (1998)
Luksan, L., Vlcek, J.: Globally convergent variable metric method for nonconvex nondifferentiable unconstrained minimization. J. Optim. Theory Appl. 111, 407–430 (2001)
Lewis, A.S., Overton, M.L.: Nonsmooth optimization via quasi-Newton methods. Math. Program. Ser. A 141, 135–163 (2013)
Burke, J., Lewis, A., Overton, M.: A robust gradient sampling algorithm for nonsmooth, nonconvex optimization. SIAM J. Optim. 15, 571–779 (2005)
Kiwiel, K.C.: Convergence of the gradient sampling algorithm for nonsmooth nonconvex optimization. SIAM J. Optim. 18(2), 379–388 (2007)
Karmitsa, N., Bagirov, A.: Limited memory discrete gradient bundle method for nonsmooth derivative-free optimization. Optimization 61(12), 1491–1509 (2012)
Conn, A., Gould, N., Toint, PhL: Trust-Region Methods. Society for Industrial and Applied Mathematics, Philadelphia (2000)
Kiwiel, K.: Methods of Descent for Nondifferentiable Optimization. Lecture Notes in Mathematics, vol. 1133. Springer, Berlin (1985)
Fletcher, R.: A model algorithm for composite nondifferentiable optimization problem. Math. Program. Studies 17, 67–76 (1982)
Fletcher, R.: An \(\ell _1\)-penalty method for nonlinear constraints. In: Boggs, P.T., Byrd, R.H., Schnabel, R.B. (eds.) Numerical Optimization, pp. 26–40. SIAM, Philadelphia (1984)
Powell, M.: General algorithms for discrete nonlinear approximation calculations. In: Chui, C.K., Schumaker, L.L., Wards, J.D. (eds.) Approximation Theory IV, pp. 187–218. Academic Press, London (1983)
Yuan, Y.: Global convergence of trust region algorithms for nonsmooth optimization. Techical Report DAMTP1983/NA13, Department of Applied Mathematics and Theoretical Physics, Cambridge University (1983)
Zhang, J., Kim, N., Lasdon, L.: An improved successive linear programming algorithm. Manag. Sci. 31, 1312–1331 (1985)
Duff, I., Nocedal, J., Reid, J.: The use of linear programming for the solution of sparse sets of nonlinear equations. SIAM J. Sci. Stat. Comput. 8, 99–108 (1987)
Hallabi, M.E., Tapia, R.: A global convergence theory for arbitraty norm trust region methods for nonlinear equations. Mathematical Sciences Technical Report, TR 87–25, Rice University, Houston, TX (1987)
Clarke, F.: Optim. Nonsmooth Anal. Society for Industrial and Applied Mathematics, Philadelphia (1987)
Dennis, J., Li, S., Tapia, R.: A unified approach to global convergence of trust region methods for nonsmooth optimization. Math. Program. 68, 319–346 (1995)
Qi, L., Sun, J.: A trust region algorithm for minimization of locally Lipschitzian functions. Math. Program. 66, 25–43 (1994)
Goldstein, A.: Optimization of Lipschitz continuous functions. Math. Program. 13, 14–22 (1977)
Bertsekas, D., Mitter, S.: A descent numerical method for optimization problems with nondifferentiable cost functionals. SIAM J. Control Optim. 11, 637–652 (1973)
Gaudioso, M., Monaco, M.: A bundle type approach to the unconstrained minimization of convex nonsmooth functions. Math. Program. 23(2), 216–226 (1982)
Mahdavi-Amiri, N., Yousefpour, R.: An effective nonsmooth optimization algorithm for locally Lipschitz functions. J. Optim. Theory Appl. 155, 180–195 (2012)
Wolfe, P.: A method of conjugate subgradients for minimizing non-differentiable functions. Math. Program. Studies 3, 145–173 (1975)
Nocedal, J., Wright, S.: Numerical Optimization, 2nd edn. Springer, Berlin (1999)
Dolan, E., More, J.: Benchmarking optimization software with performance profiles. Math. Program. 91, 201–213 (2002)
Haarala, N., Miettinen, K., Mäkelä, M.: Globally convergent limited memory bundle method for large-scale nonsmooth optimization. Math. Program. 109, 181–205 (2007)
Luksan, L., Tuma, M., Siska, M., Vlcek, J., Ramesova, N.: UFO 2002: interactive system for universal functional optimization. Technical Report, Academy of Sciences of the Czech Republic (2002). Available online at http://www.cs.cas.cz/luksan/ufo
Luksan, L., Vlcek, J.: Globally convergent variable metric method for convex nonsmooth unconstrained minimization. J. Optim. Theory Appl. 102, 593–613 (1999)
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The authors would like to thank the research councils of K.N. Toosi University of Technology and Mazandaran University for supporting this work.
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Akbari, Z., Yousefpour, R. & Reza Peyghami, M. A New Nonsmooth Trust Region Algorithm for Locally Lipschitz Unconstrained Optimization Problems. J Optim Theory Appl 164, 733–754 (2015). https://doi.org/10.1007/s10957-014-0534-6
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DOI: https://doi.org/10.1007/s10957-014-0534-6