A Modern Introduction to Online Learning
- URL: http://arxiv.org/abs/1912.13213v6
- Date: Sun, 28 May 2023 03:00:10 GMT
- Title: A Modern Introduction to Online Learning
- Authors: Francesco Orabona
- Abstract summary: Online learning refers to the framework of minimization of regret under worst-case assumptions.
I present first-order and second-order algorithms for online learning with convex losses.
- Score: 15.974402990630402
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: In this monograph, I introduce the basic concepts of Online Learning through
a modern view of Online Convex Optimization. Here, online learning refers to
the framework of regret minimization under worst-case assumptions. I present
first-order and second-order algorithms for online learning with convex losses,
in Euclidean and non-Euclidean settings. All the algorithms are clearly
presented as instantiation of Online Mirror Descent or
Follow-The-Regularized-Leader and their variants. Particular attention is given
to the issue of tuning the parameters of the algorithms and learning in
unbounded domains, through adaptive and parameter-free online learning
algorithms. Non-convex losses are dealt through convex surrogate losses and
through randomization. The bandit setting is also briefly discussed, touching
on the problem of adversarial and stochastic multi-armed bandits. These notes
do not require prior knowledge of convex analysis and all the required
mathematical tools are rigorously explained. Moreover, all the included proofs
have been carefully chosen to be as simple and as short as possible.
Related papers
- A Simple Learning-Augmented Algorithm for Online Packing with Concave Objectives [4.9826534303287335]
We introduce and analyze a simple learning-augmented algorithm for online packing problems with linear constraints and concave objectives.
We further raise the problem of understanding necessary and sufficient conditions for when such simple black-box solutions may be optimal.
arXiv Detail & Related papers (2024-06-05T18:39:28Z) - A note on continuous-time online learning [13.796981813494199]
In online learning, the data is provided in a sequential order, and the goal of the learner is to make online decisions to minimize overall regrets.
This note is concerned with continuous-time models and algorithms for several online learning problems: online linear optimization, adversarial bandit, and adversarial linear bandit.
arXiv Detail & Related papers (2024-05-16T18:58:19Z) - Efficient Methods for Non-stationary Online Learning [67.3300478545554]
We present efficient methods for optimizing dynamic regret and adaptive regret, which reduce the number of projections per round from $mathcalO(log T)$ to $1$.
Our technique hinges on the reduction mechanism developed in parameter-free online learning and requires non-trivial twists on non-stationary online methods.
arXiv Detail & Related papers (2023-09-16T07:30:12Z) - Meta-Learning Adversarial Bandit Algorithms [55.72892209124227]
We study online meta-learning with bandit feedback.
We learn to tune online mirror descent generalization (OMD) with self-concordant barrier regularizers.
arXiv Detail & Related papers (2023-07-05T13:52:10Z) - Online Prediction in Sub-linear Space [15.773280101995676]
We provide the first sub-linear space and sub-linear regret algorithm for online learning with expert advice (against an oblivious adversary)
We also demonstrate a separation between oblivious and (strong) adaptive adversaries by proving a linear memory lower bound of any sub-linear regret algorithm against an adaptive adversary.
arXiv Detail & Related papers (2022-07-16T16:15:39Z) - Implicit Parameter-free Online Learning with Truncated Linear Models [51.71216912089413]
parameter-free algorithms are online learning algorithms that do not require setting learning rates.
We propose new parameter-free algorithms that can take advantage of truncated linear models through a new update that has an "implicit" flavor.
Based on a novel decomposition of the regret, the new update is efficient, requires only one gradient at each step, never overshoots the minimum of the truncated model, and retains the favorable parameter-free properties.
arXiv Detail & Related papers (2022-03-19T13:39:49Z) - Smoothed Online Learning is as Easy as Statistical Learning [77.00766067963195]
We provide the first oracle-efficient, no-regret algorithms in this setting.
We show that if a function class is learnable in the classical setting, then there is an oracle-efficient, no-regret algorithm for contextual bandits.
arXiv Detail & Related papers (2022-02-09T19:22:34Z) - Boosting for Online Convex Optimization [64.15578413206715]
We consider the decision-making framework of online convex optimization with a large number of experts.
We define a weak learning algorithm as a mechanism that guarantees approximate regret against a base class of experts.
We give an efficient boosting algorithm that guarantees near-optimal regret against the convex hull of the base class.
arXiv Detail & Related papers (2021-02-18T12:30:49Z) - Optimal Robustness-Consistency Trade-offs for Learning-Augmented Online
Algorithms [85.97516436641533]
We study the problem of improving the performance of online algorithms by incorporating machine-learned predictions.
The goal is to design algorithms that are both consistent and robust.
We provide the first set of non-trivial lower bounds for competitive analysis using machine-learned predictions.
arXiv Detail & Related papers (2020-10-22T04:51:01Z)
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.