# Robust Model Selection and Nearly-Proper Learning for GMMs

arXiv: https://arxiv.org/abs/2106.02774 · HTML: https://mlsanity.com/paper/2106.02774/

## Key facts

- Cited by 3 papers in the map (data through 14 Oct 2026).
- Builds on 23 of its 80 references that are in the map.
- First posted on arXiv 5 Jun 2021.

## Builds on (most cited first, 23 of 23)

- [Mixture Models, Robustness, and Sum of Squares Proofs](https://mlsanity.com/paper/1711.07454/) (2017)
- [List-Decodable Robust Mean Estimation and Learning Mixtures of Spherical Gaussians](https://mlsanity.com/paper/1711.07211/) (2017)
- [Active Regression via Linear-Sample Sparsification](https://mlsanity.com/paper/1711.10051/) (2017)
- [Settling the Robust Learnability of Mixtures of Gaussians](https://mlsanity.com/paper/2011.03622/) (2020)
- [Tight bounds for learning a mixture of two gaussians](https://mlsanity.com/paper/1404.4997/) (2014)
- [Learning Mixtures of Gaussians in High Dimensions](https://mlsanity.com/paper/1503.00424/) (2015)
- [Robustly Learning any Clusterable Mixture of Gaussians](https://mlsanity.com/paper/2005.06417/) (2020)
- [Near-optimal-sample estimators for spherical Gaussian mixtures](https://mlsanity.com/paper/1402.4746/) (2014)
- [Faster and Sample Near-Optimal Algorithms for Proper Learning Mixtures of Gaussians](https://mlsanity.com/paper/1312.1054/) (2013)
- [Smoothed Analysis of Tensor Decompositions](https://mlsanity.com/paper/1311.3651/) (2013)
- [Clustering subgaussian mixtures by semidefinite programming](https://mlsanity.com/paper/1602.06612/) (2016)
- [The More, the Merrier: the Blessing of Dimensionality for Learning Large Gaussian Mixtures](https://mlsanity.com/paper/1311.2891/) (2013)
- [Self-regularizing Property of Nonparametric Maximum Likelihood Estimator in Mixture Models](https://mlsanity.com/paper/2008.08244/) (2020)
- [Sample-Optimal Density Estimation in Nearly-Linear Time](https://mlsanity.com/paper/1506.00671/) (2015)
- [Robust Learning of Mixtures of Gaussians](https://mlsanity.com/paper/2007.05912/) (2020)
- [A Universal Sampling Method for Reconstructing Signals with Simple Fourier Transforms](https://mlsanity.com/paper/1812.08723/) (2018)
- [Learning GMMs with Nearly Optimal Robustness Guarantees](https://mlsanity.com/paper/2104.09665/) (2021)
- [Model Selection for Gaussian Mixture Models](https://mlsanity.com/paper/1301.3558/) (2013)
- [Fourier-sparse interpolation without a frequency gap](https://mlsanity.com/paper/1609.01361/) (2016)
- [Super-Resolution Off the Grid](https://mlsanity.com/paper/1509.07943/) (2015)
- [A Robust Sparse Fourier Transform in the Continuous Setting](https://mlsanity.com/paper/1609.00896/) (2016)
- [Sparse Solutions to Nonnegative Linear Systems and Applications](https://mlsanity.com/paper/1501.01689/) (2015)
- [Junta Distance Approximation with Sub-Exponential Queries](https://mlsanity.com/paper/2106.00287/) (2021)

## Built on by (most cited first, 3 of 3)

- [Polynomial Time and Private Learning of Unbounded Gaussian Mixture Models](https://mlsanity.com/paper/2303.04288/) (2023)
- [Mixtures of Gaussians are Privately Learnable with a Polynomial Number of Samples](https://mlsanity.com/paper/2309.03847/) (2023)
- [Density estimation for Hellinger via minimum-distance estimators: mixtures of Gaussians, log-concave, and more](https://mlsanity.com/paper/2606.11469/) (2026)

## Abstract (arXiv)

In learning theory, a standard assumption is that the data is generated from a finite mixture model. But what happens when the number of components is not known in advance? The problem of estimating the number of components, also called model selection, is important in its own right but there are essentially no known efficient algorithms with provable guarantees let alone ones that can tolerate adversarial corruptions. In this work, we study the problem of robust model selection for univariate Gaussian mixture models (GMMs). Given textsfpoly(k/ε) samples from a distribution that is ε-close in TV distance to a GMM with k components, we can construct a GMM with widetildeO(k) components that approximates the distribution to within widetildeO(ε) in textsfpoly(k/ε) time. Thus we are able to approximately determine the minimum number of components needed to fit the distribution within a logarithmic factor. Prior to our work, the only known algorithms for learning arbitrary univariate GMMs either output significantly more than k components (e.g. k/ε2 components for kernel density estimates) or run in time exponential in k. Moreover, by adapting our techniques we obtain similar results for reconstructing Fourier-sparse signals.
