How good is PAC-Bayes at explaining generalisation?
Not on the map. Why?
Abstract (arXiv)
We discuss necessary conditions for a PAC-Bayes bound to provide a meaningful generalisation guarantee. Our analysis reveals that the optimal generalisation guarantee depends solely on the distribution of the risk induced by the prior distribution. In particular, achieving a target generalisation level is only achievable if the prior places sufficient mass on high-performing predictors. We relate these requirements to the prevalent practice of using data-dependent priors in deep learning PAC-Bayes applications, and discuss the implications for the claim that PAC-Bayes ``explains'' generalisation.
Key facts. Cited by 4 papers in the map (data through 7 Oct 2026). Builds on 16 of its 31 references that are in the map. First posted on arXiv 11 Mar 2025.
Builds on
16 of 31 references.
References · 16
- 2017Deep Neural Networks as Gaussian Processescited by 617
- 2017Computing Nonvacuous Generalization Bounds for Deep (Stochastic) Neural Networks with Many More Parameters than Training Datacited by 527
- 2021User-friendly introduction to PAC-Bayes boundscited by 234
- 2016Deep Information Propagationcited by 194
- 2019A Primer on PAC-Bayesian Learningcited by 130
- 2018Non-Vacuous Generalization Bounds at the ImageNet Scale: A PAC-Bayesian Compression Approachcited by 125
- 2020Tighter risk certificates for neural networkscited by 112
- 2019On the Impact of the Activation Function on Deep Neural Networks Trainingcited by 101
- 2022PAC-Bayes Compression Bounds So Tight That They Can Explain Generalizationcited by 75
- 2020On the role of data in PAC-Bayes boundscited by 64
- 2016Simpler PAC-Bayesian Bounds for Hostile Datacited by 45
- 2019PAC-Bayes Un-Expected Bernstein Inequalitycited by 36
4 more
- 2021Learning PAC-Bayes Priors for Probabilistic Neural Networkscited by 21
- 2023Tighter PAC-Bayes Bounds Through Coin-Bettingcited by 13
- 2023Learning via Wasserstein-Based High Probability Generalisation Boundscited by 11
- 2021Conditionally Gaussian PAC-Bayescited by 7
Built on by
Citing papers per year: 2025: 1; 2026: 3.
4 papers.
- 2025The Alignment Bottleneckcited by 1
- 2026Empirical Risk Minimization with f-Divergence Regularizationcited by 0
- 2026Can Circuit Alignment Predict OOD Generalization?cited by 0
- 2026Certification Frontiers for Gaussian LoRA: Independent Priors, Posterior Risk, and Prediction-Preserving Balancingcited by 0
- 2026Certification Frontiers for Gaussian LoRA: Independent Priors, Posterior Risk, and Prediction-Preserving Balancing26 Sep 2026
- 2026Can Circuit Alignment Predict OOD Generalization?25 Sep 2026
- 2026Empirical Risk Minimization with f-Divergence Regularization19 Jan 2026
- 2025The Alignment Bottleneck19 Sep 2025