# Fast Rate Information-theoretic Bounds on Generalization Errors

arXiv: https://arxiv.org/abs/2303.14658 · HTML: https://mlsanity.com/paper/2303.14658/

## Key facts

- Cited by 5 papers in the map (data through 14 Oct 2026).
- Builds on 19 of its 47 references that are in the map.
- First posted on arXiv 26 Mar 2023.

## Builds on (most cited first, 19 of 19)

- [Information-theoretic analysis of generalization capability of learning algorithms](https://mlsanity.com/paper/1705.07809/) (2017)
- [User-friendly introduction to PAC-Bayes bounds](https://mlsanity.com/paper/2110.11216/) (2021)
- [Reasoning About Generalization via Conditional Mutual Information](https://mlsanity.com/paper/2001.09122/) (2020)
- [Information-Theoretic Generalization Bounds for SGLD via Data-Dependent Estimates](https://mlsanity.com/paper/1911.02151/) (2019)
- [Tightening Mutual Information Based Bounds on Generalization Error](https://mlsanity.com/paper/1901.04609/) (2019)
- [Sharpened Generalization Bounds based on Conditional Mutual Information and an Application to Noisy, Iterative Algorithms](https://mlsanity.com/paper/2004.12983/) (2020)
- [Chaining Mutual Information and Tightening Generalization Bounds](https://mlsanity.com/paper/1806.03803/) (2018)
- [Fast rates in statistical and online learning](https://mlsanity.com/paper/1507.02592/) (2015)
- [Generalization Bounds via Information Density and Conditional Information Density](https://mlsanity.com/paper/2005.08044/) (2020)
- [PAC-Bayes Un-Expected Bernstein Inequality](https://mlsanity.com/paper/1905.13367/) (2019)
- [Estimating Mutual Information for Discrete-Continuous Mixtures](https://mlsanity.com/paper/1709.06212/) (2017)
- [PAC-Bayes, MAC-Bayes and Conditional Mutual Information: Fast rate bounds that handle general VC classes](https://mlsanity.com/paper/2106.09683/) (2021)
- [Individually Conditional Individual Mutual Information Bound on Generalization Error](https://mlsanity.com/paper/2012.09922/) (2020)
- [On Random Subset Generalization Error Bounds and the Stochastic Gradient Langevin Dynamics Algorithm](https://mlsanity.com/paper/2010.10994/) (2020)
- [A New Family of Generalization Bounds Using Samplewise Evaluated CMI](https://mlsanity.com/paper/2210.06422/) (2022)
- [Fast Rates for General Unbounded Loss Functions: from ERM to Generalized Bayes](https://mlsanity.com/paper/1605.00252/) (2016)
- [Refined Error Bounds for Several Learning Algorithms](https://mlsanity.com/paper/1512.07146/) (2015)
- [Semi-Supervised Learning: the Case When Unlabeled Data is Equally Useful](https://mlsanity.com/paper/2005.11018/) (2020)
- [Fast Rate Generalization Error Bounds: Variations on a Theme](https://mlsanity.com/paper/2205.03131/) (2022)

## Built on by (most cited first, 5 of 5)

- [Sample-Conditioned Hypothesis Stability Sharpens Information-Theoretic Generalization Bounds](https://mlsanity.com/paper/2310.20102/) (2023)
- [Comparing Comparators in Generalization Bounds](https://mlsanity.com/paper/2310.10534/) (2023)
- [On the Generalization of Knowledge Distillation: An Information-Theoretic View](https://mlsanity.com/paper/2605.13143/) (2026)
- [Block-Sample MAC-Bayes Generalization Bounds](https://mlsanity.com/paper/2602.12605/) (2026)
- [Generalization Theory for Through-the-Wall Radar Human Activity Recognition](https://mlsanity.com/paper/2607.08144/) (2026)

## Abstract (arXiv)

The generalization error of a learning algorithm refers to the discrepancy between the loss of a learning algorithm on training data and that on unseen testing data. Various information-theoretic bounds on the generalization error have been derived in the literature, where the mutual information between the training data and the hypothesis (the output of the learning algorithm) plays an important role. Focusing on the individual sample mutual information bound by Bu et al., which itself is a tightened version of the first bound on the topic by Russo et al. and Xu et al., this paper investigates the tightness of these bounds, in terms of the dependence of their convergence rates on the sample size n. It has been recognized that these bounds are in general not tight, readily verified for the exemplary quadratic Gaussian mean estimation problem, where the individual sample mutual information bound scales as O(√1/n) while the true generalization error scales as O(1/n). The first contribution of this paper is to show that the same bound can in fact be asymptotically tight if an appropriate assumption is made. In particular, we show that the fast rate can be recovered when the assumption is made on the excess risk instead of the loss function, which was usually done in existing literature. A theoretical justification is given for this choice. The second contribution of the paper is a new set of generalization error bounds based on the (η, c)-central condition, a condition relatively easy to verify and has the property that the mutual information term directly determines the convergence rate of the bound. Several analytical and numerical examples are given to show the effectiveness of these bounds.
