Exact Acceleration of K-Means++ and K-Means||

Exact Acceleration of K-Means++ and K-Means||

Edward Raff

Proceedings of the Thirtieth International Joint Conference on Artificial Intelligence
Main Track. Pages 2928-2935. https://doi.org/10.24963/ijcai.2021/403

K-Means++ and its distributed variant K-Means|| have become de facto tools for selecting the initial seeds of K-means. While alternatives have been developed, the effectiveness, ease of implementation,and theoretical grounding of the K-means++ and || methods have made them difficult to "best" from a holistic perspective. We focus on using triangle inequality based pruning methods to accelerate both of these algorithms to yield comparable or better run-time without sacrificing any of the benefits of these approaches. For both algorithms we are able to reduce distance computations by over 500×. For K-means++ this results in up to a 17×speedup in run-time and a551×speedup for K-means||. We achieve this with simple, but carefully chosen, modifications to known techniques which makes it easy to integrate our approach into existing implementations of these algorithms.
Keywords:
Machine Learning: Clustering
Machine Learning Applications: Big data; Scalability
Data Mining: Clustering