# Almost Asymptotically Optimal Active Clustering Through Pairwise Observations

arXiv: https://arxiv.org/abs/2602.05690 · HTML: https://mlsanity.com/paper/2602.05690/

## Key facts

- No citing papers in the map yet (data through 14 Oct 2026).
- Builds on 17 of its 48 references that are in the map.
- First posted on arXiv 5 Feb 2026.

## Builds on (most cited first, 17 of 17)

- [Community Detection and Stochastic Block Models](https://mlsanity.com/paper/1703.10146/) (2017)
- [Optimal Best Arm Identification with Fixed Confidence](https://mlsanity.com/paper/1602.04589/) (2016)
- [Online Clustering of Bandits](https://mlsanity.com/paper/1401.8257/) (2014)
- [Mixture Martingales Revisited with Applications to Sequential Tests and Confidence Intervals](https://mlsanity.com/paper/1811.11419/) (2018)
- [Optimal Best-arm Identification in Linear Bandits](https://mlsanity.com/paper/2006.16073/) (2020)
- [Clustering with Noisy Queries](https://mlsanity.com/paper/1706.07510/) (2017)
- [Correlation Clustering with Same-Cluster Queries Bounded by Optimal Cost](https://mlsanity.com/paper/1908.04976/) (2019)
- [Optimal Exploitation of Clustering and History Information in Multi-Armed Bandit](https://mlsanity.com/paper/1906.03979/) (2019)
- [Multi-Armed Bandits with Dependent Arms](https://mlsanity.com/paper/2010.09478/) (2020)
- [Dealing With Misspecification In Fixed-Confidence Linear Top-m Identification](https://mlsanity.com/paper/2111.01479/) (2021)
- [Towards a Query-Optimal and Time-Efficient Algorithm for Clustering with a Faulty Oracle](https://mlsanity.com/paper/2106.10374/) (2021)
- [Recovering Unbalanced Communities in the Stochastic Block Model With Application to Clustering with a Faulty Oracle](https://mlsanity.com/paper/2202.08522/) (2022)
- [Optimal Clustering with Noisy Queries via Multi-Armed Bandit](https://mlsanity.com/paper/2207.05376/) (2022)
- [On the Sample Complexity of Representation Learning in Multi-task Bandits with Global and Local structure](https://mlsanity.com/paper/2211.15129/) (2022)
- [Optimal Multi-Objective Best Arm Identification with Fixed Confidence](https://mlsanity.com/paper/2501.13607/) (2025)
- [Mixed Membership Graph Clustering via Systematic Edge Query](https://mlsanity.com/paper/2011.12988/) (2020)
- [Near Optimal Pure Exploration in Logistic Bandits](https://mlsanity.com/paper/2410.20640/) (2024)

## Abstract (arXiv)

We propose a new analysis framework for clustering M items into an unknown number of K distinct groups using noisy and actively collected responses. At each time step, an agent is allowed to query pairs of items and observe bandit binary feedback. If the pair of items belongs to the same (resp. different) cluster, the observed feedback is 1 with probability p>1/2 (resp. q<1/2). Leveraging the ubiquitous change-of-measure technique, we establish a fundamental lower bound on the expected number of queries needed to achieve a desired confidence in the clustering accuracy, formulated as a sup-inf optimization problem. Building on this theoretical foundation, we design an asymptotically optimal algorithm in which the stopping criterion involves an empirical version of the inner infimum -- the Generalized Likelihood Ratio (GLR) statistic -- being compared to a threshold. We develop a computationally feasible variant of the GLR statistic and show that its performance gap to the lower bound can be accurately empirically estimated and remains within a constant multiple of the lower bound.
