Using Stochastic Gradient Descent to Smooth Nonconvex Functions: Analysis of Implicit Graduated Optimization
- URL: http://arxiv.org/abs/2311.08745v5
- Date: Wed, 23 Oct 2024 09:40:44 GMT
- Title: Using Stochastic Gradient Descent to Smooth Nonconvex Functions: Analysis of Implicit Graduated Optimization
- Authors: Naoki Sato, Hideaki Iiduka,
- Abstract summary: We show that noise in batch descent gradient (SGD) has the effect of smoothing objective function.
We analyze a new graduated optimization algorithm that varies the degree of smoothing by learning rate and batch size.
- Score: 0.6906005491572401
- License:
- Abstract: The graduated optimization approach is a heuristic method for finding global optimal solutions for nonconvex functions by using a function smoothing operation with stochastic noise. We show that stochastic noise in stochastic gradient descent (SGD) has the effect of smoothing the objective function, the degree of which is determined by the learning rate, batch size, and variance of the stochastic gradient. Using this finding, we propose and analyze a new graduated optimization algorithm that varies the degree of smoothing by varying the learning rate and batch size, and provide experimental results on image classification tasks with ResNets that support our theoretical findings. We further show that there is an interesting correlation between the degree of smoothing by SGD's stochastic noise, the well-studied ``sharpness'' indicator, and the generalization performance of the model.
Related papers
- Gradient Normalization with(out) Clipping Ensures Convergence of Nonconvex SGD under Heavy-Tailed Noise with Improved Results [60.92029979853314]
This paper investigates Gradient Normalization without (NSGDC) its gradient reduction variant (NSGDC-VR)
We present significant improvements in the theoretical results for both algorithms.
arXiv Detail & Related papers (2024-10-21T22:40:42Z) - Dynamic Anisotropic Smoothing for Noisy Derivative-Free Optimization [0.0]
We propose a novel algorithm that extends the methods of ball smoothing and Gaussian smoothing for noisy derivative-free optimization.
The algorithm dynamically adapts the shape of the smoothing kernel to approximate the Hessian of the objective function around a local optimum.
arXiv Detail & Related papers (2024-05-02T21:04:20Z) - Learning Unnormalized Statistical Models via Compositional Optimization [73.30514599338407]
Noise-contrastive estimation(NCE) has been proposed by formulating the objective as the logistic loss of the real data and the artificial noise.
In this paper, we study it a direct approach for optimizing the negative log-likelihood of unnormalized models.
arXiv Detail & Related papers (2023-06-13T01:18:16Z) - Computing the Variance of Shuffling Stochastic Gradient Algorithms via
Power Spectral Density Analysis [6.497816402045099]
Two common alternatives to gradient descent (SGD) with theoretical benefits are random reshuffling (SGDRR) and shuffle-once (SGD-SO)
We study the stationary variances of SGD, SGDRR and SGD-SO, whose leading terms decrease in this order, and obtain simple approximations.
arXiv Detail & Related papers (2022-06-01T17:08:04Z) - A Closed Loop Gradient Descent Algorithm applied to Rosenbrock's
function [0.0]
We introduce a novel adaptive technique for an gradient system which finds application as a gradient descent algorithm for unconstrained inertial damping.
Also using Lyapunov stability analysis, we demonstrate the performance of the continuous numerical-time version of the algorithm.
arXiv Detail & Related papers (2021-08-29T17:25:24Z) - Differentiable Annealed Importance Sampling and the Perils of Gradient
Noise [68.44523807580438]
Annealed importance sampling (AIS) and related algorithms are highly effective tools for marginal likelihood estimation.
Differentiability is a desirable property as it would admit the possibility of optimizing marginal likelihood as an objective.
We propose a differentiable algorithm by abandoning Metropolis-Hastings steps, which further unlocks mini-batch computation.
arXiv Detail & Related papers (2021-07-21T17:10:14Z) - High Probability Complexity Bounds for Non-Smooth Stochastic Optimization with Heavy-Tailed Noise [51.31435087414348]
It is essential to theoretically guarantee that algorithms provide small objective residual with high probability.
Existing methods for non-smooth convex optimization have complexity bounds with dependence on confidence level.
We propose novel stepsize rules for two methods with gradient clipping.
arXiv Detail & Related papers (2021-06-10T17:54:21Z) - Zeroth-Order Hybrid Gradient Descent: Towards A Principled Black-Box
Optimization Framework [100.36569795440889]
This work is on the iteration of zero-th-order (ZO) optimization which does not require first-order information.
We show that with a graceful design in coordinate importance sampling, the proposed ZO optimization method is efficient both in terms of complexity as well as as function query cost.
arXiv Detail & Related papers (2020-12-21T17:29:58Z) - An adaptive stochastic gradient-free approach for high-dimensional
blackbox optimization [0.0]
We propose an adaptive gradient-free (ASGF) approach for high-dimensional non-smoothing problems.
We illustrate the performance of this method on benchmark global problems and learning tasks.
arXiv Detail & Related papers (2020-06-18T22:47:58Z) - Towards Better Understanding of Adaptive Gradient Algorithms in
Generative Adversarial Nets [71.05306664267832]
Adaptive algorithms perform gradient updates using the history of gradients and are ubiquitous in training deep neural networks.
In this paper we analyze a variant of OptimisticOA algorithm for nonconcave minmax problems.
Our experiments show that adaptive GAN non-adaptive gradient algorithms can be observed empirically.
arXiv Detail & Related papers (2019-12-26T22:10:10Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.