# Data-Driven Online Model Selection With Regret Guarantees

arXiv: https://arxiv.org/abs/2306.02869 · HTML: https://mlsanity.com/paper/2306.02869/

## Key facts

- Cited by 11 papers in the map (data through 14 Oct 2026).
- Builds on 14 of its 33 references that are in the map.
- First posted on arXiv 5 Jun 2023.

## Builds on (most cited first, 14 of 14)

- [Corralling a Band of Bandit Algorithms](https://mlsanity.com/paper/1612.06246/) (2016)
- [Adapting to Misspecification in Contextual Bandits](https://mlsanity.com/paper/2107.05745/) (2021)
- [Model Selection in Contextual Stochastic Bandit Problems](https://mlsanity.com/paper/2003.01704/) (2020)
- [Model selection for contextual bandits](https://mlsanity.com/paper/1906.00531/) (2019)
- [Regret Bound Balancing and Elimination for Model Selection in Bandits and RL](https://mlsanity.com/paper/2012.13045/) (2020)
- [A Model Selection Approach for Corruption Robust Reinforcement Learning](https://mlsanity.com/paper/2110.03580/) (2021)
- [OSOM: A simultaneously optimal algorithm for multi-armed and linear contextual bandits](https://mlsanity.com/paper/1905.10040/) (2019)
- [Online Model Selection for Reinforcement Learning with Function Approximation](https://mlsanity.com/paper/2011.09750/) (2020)
- [Problem-Complexity Adaptive Model Selection for Stochastic Linear Bandits](https://mlsanity.com/paper/2006.02612/) (2020)
- [The Pareto Frontier of model selection for general Contextual Bandits](https://mlsanity.com/paper/2110.13282/) (2021)
- [Corralling Stochastic Bandit Algorithms](https://mlsanity.com/paper/2006.09255/) (2020)
- [Regret Balancing for Bandit and RL Model Selection](https://mlsanity.com/paper/2006.05491/) (2020)
- [Best of Both Worlds Model Selection](https://mlsanity.com/paper/2206.14912/) (2022)
- [Rate-adaptive model selection over a collection of black-box contextual bandit algorithms](https://mlsanity.com/paper/2006.03632/) (2020)

## Built on by (most cited first, 11 of 11)

- [Efficient Sequential Decision Making with Large Language Models](https://mlsanity.com/paper/2406.12125/) (2024)
- [BOAD: Discovering Hierarchical Software Engineering Agents via Bandit Optimization](https://mlsanity.com/paper/2512.23631/) (2025)
- [Reinforcement Learning in the Real World: A Survey of Statistical Challenges and Future Directions](https://mlsanity.com/paper/2601.15353/) (2026)
- [Symmetric Linear Bandits with Hidden Symmetry](https://mlsanity.com/paper/2405.13899/) (2024)
- [Managing Self-Learning Experts under Per-Round Budget Constraints](https://mlsanity.com/paper/2510.22654/) (2025)
- [Learning Rate-Free Reinforcement Learning: A Case for Model Selection with Non-Stationary Objectives](https://mlsanity.com/paper/2408.04046/) (2024)
- [Complexity as Advantage: A Regret-Based Perspective on Emergent Structure](https://mlsanity.com/paper/2511.04590/) (2025)
- [Empirical Comparison of Forgetting Mechanisms for UCB-based Algorithms on a Data-Driven Simulation Platform](https://mlsanity.com/paper/2511.19240/) (2025)
- [Improved Training Mechanism for Reinforcement Learning via Online Model Selection](https://mlsanity.com/paper/2512.02214/) (2025)
- [Bayesian Online Model Selection](https://mlsanity.com/paper/2602.17958/) (2026)
- [Beyond Static Bias: Adaptive Multi-Fidelity Bandits with Improving Proxies](https://mlsanity.com/paper/2605.08558/) (2026)

## Abstract (arXiv)

We consider model selection for sequential decision making in stochastic environments with bandit feedback, where a meta-learner has at its disposal a pool of base learners, and decides on the fly which action to take based on the policies recommended by each base learner. Model selection is performed by regret balancing but, unlike the recent literature on this subject, we do not assume any prior knowledge about the base learners like candidate regret guarantees; instead, we uncover these quantities in a data-driven manner. The meta-learner is therefore able to leverage the realized regret incurred by each base learner for the learning environment at hand (as opposed to the expected regret), and single out the best such regret. We design two model selection algorithms operating with this more ambitious notion of regret and, besides proving model selection guarantees via regret balancing, we experimentally demonstrate the compelling practical benefits of dealing with actual regrets instead of candidate regret bounds.
