# Smoothed Analysis for Learning Concepts with Low Intrinsic Dimension

arXiv: https://arxiv.org/abs/2407.00966 · HTML: https://mlsanity.com/paper/2407.00966/

## Key facts

- Cited by 11 papers in the map (data through 14 Oct 2026).
- Builds on 20 of its 78 references that are in the map.
- First posted on arXiv 1 Jul 2024.

## Builds on (most cited first, 20 of 20)

- [Distribution-Independent PAC Learning of Halfspaces with Massart Noise](https://mlsanity.com/paper/1906.10075/) (2019)
- [Statistical Query Algorithms and Low-Degree Tests Are Almost Equivalent](https://mlsanity.com/paper/2009.06107/) (2020)
- [Complexity Theoretic Limitations on Learning Halfspaces](https://mlsanity.com/paper/1505.05800/) (2015)
- [Learning Halfspaces with Massart Noise Under Structured Distributions](https://mlsanity.com/paper/2002.05632/) (2020)
- [Statistical Query Algorithms for Mean Vector Estimation and Stochastic Convex Optimization](https://mlsanity.com/paper/1512.09170/) (2015)
- [Efficient Learning of Linear Separators under Bounded Noise](https://mlsanity.com/paper/1503.03594/) (2015)
- [Efficient active learning of sparse halfspaces with arbitrary bounded noise](https://mlsanity.com/paper/2002.04840/) (2020)
- [Learning General Halfspaces with General Massart Noise under the Gaussian Distribution](https://mlsanity.com/paper/2108.08767/) (2021)
- [A Moment-Matching Approach to Testable Learning and a New Characterization of Rademacher Complexity](https://mlsanity.com/paper/2211.13312/) (2022)
- [From Local Pseudorandom Generators to Hardness of Learning](https://mlsanity.com/paper/2101.08303/) (2021)
- [Efficient Truncated Statistics with Unknown Truncation](https://mlsanity.com/paper/1908.01034/) (2019)
- [Statistical Queries and Statistical Algorithms: Foundations and Applications](https://mlsanity.com/paper/2004.00557/) (2020)
- [Agnostic Proper Learning of Halfspaces under Gaussian Marginals](https://mlsanity.com/paper/2102.05629/) (2021)
- [Optimal-Degree Polynomial Approximations for Exponentials and Gaussian Kernel Density Estimation](https://mlsanity.com/paper/2205.06249/) (2022)
- [Classification Under Misspecification: Halfspaces, Generalized Linear Models, and Connections to Evolvability](https://mlsanity.com/paper/2006.04787/) (2020)
- [Computational Complexity of Learning Neural Networks: Smoothness and Degeneracy](https://mlsanity.com/paper/2302.07426/) (2023)
- [Nearly Tight Bounds for Robust Proper Learning of Halfspaces with a Margin](https://mlsanity.com/paper/1908.11335/) (2019)
- [Robust testing of low-dimensional functions](https://mlsanity.com/paper/2004.11642/) (2020)
- [Is your function low-dimensional?](https://mlsanity.com/paper/1806.10057/) (2018)
- [Most Neural Networks Are Almost Learnable](https://mlsanity.com/paper/2305.16508/) (2023)

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

- [Survey on Algorithms for multi-index models](https://mlsanity.com/paper/2504.05426/) (2025)
- [The Power of Iterative Filtering for Supervised Learning with (Heavy) Contamination](https://mlsanity.com/paper/2505.20177/) (2025)
- [Smoothed Analysis of Learning from Positive Samples](https://mlsanity.com/paper/2504.10428/) (2025)
- [Learning Juntas under Markov Random Fields](https://mlsanity.com/paper/2506.00764/) (2025)
- [Smoothed Agnostic Learning of Halfspaces over the Hypercube](https://mlsanity.com/paper/2511.17782/) (2025)
- [Sandwiching Polynomials for Geometric Concepts with Low Intrinsic Dimension](https://mlsanity.com/paper/2602.24178/) (2026)
- [Beyond Worst-Case Online Classification: VC-Based Regret Bounds for Relaxed Benchmarks](https://mlsanity.com/paper/2504.10598/) (2025)
- [Statistical Query Lower Bounds for Smoothed Agnostic Learning](https://mlsanity.com/paper/2602.21191/) (2026)
- [Learning mathsfAC0 under Locally Sampleable Graphical Models](https://mlsanity.com/paper/2607.08303/) (2026)
- [Learning Conditional Averages](https://mlsanity.com/paper/2602.11920/) (2026)
- [A Near-optimal SQ Lower Bound for Smoothed Agnostic Learning of Boolean Halfspaces](https://mlsanity.com/paper/2605.02350/) (2026)

## Abstract (arXiv)

In traditional models of supervised learning, the goal of a learner-- given examples from an arbitrary joint distribution on ℝd × ± 1-- is to output a hypothesis that is competitive (to within ε) of the best fitting concept from some class. In order to escape strong hardness results for learning even simple concept classes, we introduce a smoothed-analysis framework that requires a learner to compete only with the best classifier that is robust to small random Gaussian perturbation. This subtle change allows us to give a wide array of learning results for any concept that (1) depends on a low-dimensional subspace (aka multi-index model) and (2) has a bounded Gaussian surface area. This class includes functions of halfspaces and (low-dimensional) convex sets, cases that are only known to be learnable in non-smoothed settings with respect to highly structured distributions such as Gaussians. Our definition of smoothed agnostic learning is an interpolation between the case where the instance distribution D and the optimal classifier can be arbitrarily coupled (which corresponds to agnostic learning and σ = 0) and completely decoupled (when σ = ∞). This decoupling allows us to avoid worst-case concepts that can encode complexity-theoretic primitives. Surprisingly, our analysis also yields new results for traditional non-smoothed frameworks such as learning with margin. In particular, we obtain the first algorithm for agnostically learning intersections of k-halfspaces in time k^poly(fraclog kε γ)  where γ is the margin parameter. Before our work, the best-known runtime was exponential in k (Arriaga and Vempala, FOCS' 99).
