# K-bMOM: a robust Lloyd-type clustering algorithm based on bootstrap Median-of-Means

arXiv: https://arxiv.org/abs/2002.03899 · HTML: https://mlsanity.com/paper/2002.03899/

## Key facts

- Cited by 7 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 10 Feb 2020.

## Built on by (most cited first, 7 of 7)

- [Uniform Concentration Bounds toward a Unified Framework for Robust Clustering](https://mlsanity.com/paper/2110.14148/) (2021)
- [Robust Principal Component Analysis: A Median of Means Approach](https://mlsanity.com/paper/2102.03403/) (2021)
- [Adversarially robust clustering with optimality guarantees](https://mlsanity.com/paper/2306.09977/) (2023)
- [Robust Linear Predictions: Analyses of Uniform Concentration, Fast Rates and Model Misspecification](https://mlsanity.com/paper/2201.01973/) (2022)
- [Dirichlet Process-based Robust Clustering using the Median-of-Means Estimator](https://mlsanity.com/paper/2311.15384/) (2023)
- [On the Optimality of the Median-of-Means Estimator under Adversarial Contamination](https://mlsanity.com/paper/2510.07867/) (2025)
- [Convex Clustering Redefined: Robust Learning with the Median of Means Estimator](https://mlsanity.com/paper/2511.14784/) (2025)

## Abstract (arXiv)

We propose a new clustering algorithm that is robust to the presence of outliers in the dataset. We perform Lloyd-type iterations with robust estimates of the centroids. More precisely, we build on the idea of median-of-means statistics to estimate the centroids, but allow for replacement while constructing the blocks. We call this methodology the bootstrap median-of-means (bMOM) and prove that if enough blocks are generated through the bootstrap sampling, then it has a better breakdown point for mean estimation than the classical median-of-means (MOM), where the blocks form a partition of the dataset. From a clustering perspective, bMOM enables to take many blocks of a desired size, thus avoiding possible disappearance of clusters in some blocks, a pitfall that can occur for the partition-based generation of blocks of the classical median-of-means. Experiments on simulated datasets show that the proposed approach, called K-bMOM, performs better than existing robust K-means based methods. Guidelines are provided for tuning the hyper-parameters K-bMOM in practice. It is also recommended to the practitionner to use such a robust approach to initialize their clustering algorithm. Finally, considering a simplified and theoretical version of our estimator, we prove its robustness to adversarial contamination by deriving robust rates of convergence for the K-means distorsion. To our knowledge, it is the first result of this kind for the K-means distorsion.
