First order stochastic methods

An objective-function-free algorithm for nonconvex stochastic optimization with deterministic equality and inequality constraints

  • Serge Gratton
  • Philippe L. Toint
    • Categories Constrained Nonlinear Optimization, Nonlinear Optimization, Stochastic Programming Tags , , , ,

    An algorithm is proposed for solving optimization problems with stochastic objective and deterministic equality and inequality constraints. This algorithm is objective-function-free in the sense that it only uses the objective’s gradient and never evaluates the function value. It is based on an adaptive selection of function-decreasing and constraint-improving iterations, the first ones using an Adagrad-type … Read more

    The stochastic Ravine accelerated gradient method with general extrapolation coefficients

  • Hédy Attouch
  • Jalal Fadili
  • Vyacheslav Kungurtsev
    • Categories Convex Optimization, Nonlinear Optimization Tags ,

    Abstract: In a real Hilbert space domain setting, we study the convergence properties of the stochastic Ravine accelerated gradient method for convex differentiable optimization. We consider the general form of this algorithm where the extrapolation coefficients can vary with each iteration, and where the evaluation of the gradient is subject to random errors. This general … Read more

    A line search based proximal stochastic gradient algorithm with dynamical variance reduction

  • Giorgia Franchini
  • Federica Porta
  • Valeria Ruggiero
  • Ilaria Trombini
    • Categories Convex Optimization Tags , , ,

    Many optimization problems arising from machine learning applications can be cast as the minimization of the sum of two functions: the first one typically represents the expected risk, and in practice it is replaced by the empirical risk, and the other one imposes a priori information on the solution. Since in general the first term … Read more