Relax and penalize: a new bilevel approach to mixed-binary
hyperparameter optimization
- URL: http://arxiv.org/abs/2308.10711v1
- Date: Mon, 21 Aug 2023 13:24:52 GMT
- Title: Relax and penalize: a new bilevel approach to mixed-binary
hyperparameter optimization
- Authors: Marianna de Santis (UNIROMA), Jordan Frecon (LHC), Francesco Rinaldi
(Unipd), Saverio Salzo (DIAG UNIROMA), Martin Schmidt
- Abstract summary: We tackle the challenging optimization of mixed-binary hyper parameters.
We propose an algorithmic framework that is guaranteed to provide mixed-binary solutions.
We evaluate the performance of our approach for a specific machine learning problem.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: In recent years, bilevel approaches have become very popular to efficiently
estimate high-dimensional hyperparameters of machine learning models. However,
to date, binary parameters are handled by continuous relaxation and rounding
strategies, which could lead to inconsistent solutions. In this context, we
tackle the challenging optimization of mixed-binary hyperparameters by
resorting to an equivalent continuous bilevel reformulation based on an
appropriate penalty term. We propose an algorithmic framework that, under
suitable assumptions, is guaranteed to provide mixed-binary solutions.
Moreover, the generality of the method allows to safely use existing continuous
bilevel solvers within the proposed framework. We evaluate the performance of
our approach for a specific machine learning problem, i.e., the estimation of
the group-sparsity structure in regression problems. Reported results clearly
show that our method outperforms state-of-the-art approaches based on
relaxation and rounding
Related papers
- Towards Differentiable Multilevel Optimization: A Gradient-Based Approach [1.6114012813668932]
This paper introduces a novel gradient-based approach for multilevel optimization.
Our method significantly reduces computational complexity while improving both solution accuracy and convergence speed.
To the best of our knowledge, this is one of the first algorithms to provide a general version of implicit differentiation.
arXiv Detail & Related papers (2024-10-15T06:17:59Z) - A Stochastic Approach to Bi-Level Optimization for Hyperparameter Optimization and Meta Learning [74.80956524812714]
We tackle the general differentiable meta learning problem that is ubiquitous in modern deep learning.
These problems are often formalized as Bi-Level optimizations (BLO)
We introduce a novel perspective by turning a given BLO problem into a ii optimization, where the inner loss function becomes a smooth distribution, and the outer loss becomes an expected loss over the inner distribution.
arXiv Detail & Related papers (2024-10-14T12:10:06Z) - Contextual Stochastic Bilevel Optimization [50.36775806399861]
We introduce contextual bilevel optimization (CSBO) -- a bilevel optimization framework with the lower-level problem minimizing an expectation on some contextual information and the upper-level variable.
It is important for applications such as meta-learning, personalized learning, end-to-end learning, and Wasserstein distributionally robustly optimization with side information (WDRO-SI)
arXiv Detail & Related papers (2023-10-27T23:24:37Z) - Analyzing Inexact Hypergradients for Bilevel Learning [0.09669369645900441]
We introduce a unified framework for computing hypergradients that generalizes existing methods based on the implicit function theorem and automatic differentiation/backpropagation.
Our numerical results show that, surprisingly, for efficient bilevel optimization, the choice of hypergradient algorithm is at least as important as the choice of lower-level solver.
arXiv Detail & Related papers (2023-01-11T23:54:27Z) - Algorithm for Constrained Markov Decision Process with Linear
Convergence [55.41644538483948]
An agent aims to maximize the expected accumulated discounted reward subject to multiple constraints on its costs.
A new dual approach is proposed with the integration of two ingredients: entropy regularized policy and Vaidya's dual.
The proposed approach is shown to converge (with linear rate) to the global optimum.
arXiv Detail & Related papers (2022-06-03T16:26:38Z) - Enhanced Bilevel Optimization via Bregman Distance [104.96004056928474]
We propose a bilevel optimization method based on Bregman Bregman functions.
We also propose an accelerated version of SBiO-BreD method (ASBiO-BreD) by using the variance-reduced technique.
arXiv Detail & Related papers (2021-07-26T16:18:43Z) - 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) - Convergence Properties of Stochastic Hypergradients [38.64355126221992]
We study approximation schemes for the hypergradient, which are important when the lower-level problem is empirical risk on a large dataset.
We provide numerical experiments to support our theoretical analysis and to show the advantage of using hypergradients in practice.
arXiv Detail & Related papers (2020-11-13T20:50:36Z) - On the implementation of a global optimization method for mixed-variable
problems [0.30458514384586394]
The algorithm is based on the radial basis function of Gutmann and the metric response surface method of Regis and Shoemaker.
We propose several modifications aimed at generalizing and improving these two algorithms.
arXiv Detail & Related papers (2020-09-04T13:36:56Z) - Combining Deep Learning and Optimization for Security-Constrained
Optimal Power Flow [94.24763814458686]
Security-constrained optimal power flow (SCOPF) is fundamental in power systems.
Modeling of APR within the SCOPF problem results in complex large-scale mixed-integer programs.
This paper proposes a novel approach that combines deep learning and robust optimization techniques.
arXiv Detail & Related papers (2020-07-14T12:38:21Z) - Optimizing generalization on the train set: a novel gradient-based
framework to train parameters and hyperparameters simultaneously [0.0]
Generalization is a central problem in Machine Learning.
We present a novel approach based on a new measure of risk that allows us to develop novel fully automatic procedures for generalization.
arXiv Detail & Related papers (2020-06-11T18:04:36Z)
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.