stochastic convex composite optimization

Multi-cut stochastic approximation methods for solving stochastic convex composite optimization

  • Jiaming Liang
  • Honghao Zhang
  • Renato D.C. Monteiro
    • Categories Convex Optimization, Stochastic Programming Tags , , ,

    This paper considers the stochastic convex composite optimization problem and presents multi-cut stochastic approximation (SA) methods for solving it, whose models in expectation overestimate its objective function. The multi-cut model obtained by taking the maximum of a finite number of linearizations of the stochastic objective function provides a biased estimate of the objective function, with … Read more

    Variance Reduction and Low Sample Complexity in Stochastic Optimization via Proximal Point Method

  • Jiaming Liang
    • Categories Convex Optimization, Stochastic Programming Tags , , , , ,

    High-probability guarantees in stochastic optimization are often obtained only under strong noise assumptions such as sub-Gaussian tails. We show that such guarantees can also be achieved under the weaker assumption of bounded variance by developing a stochastic proximal point method. This method combines a proximal subproblem solver, which inherently reduces variance, with a probability booster … Read more