Deep Learning (DL) has shown great promise in the unsupervised task of clustering. That said, while in classical (i.e., non-deep) clustering the benefits of the nonparametric approach are well known, most deep-clustering methods are parametric: namely, they require a predefined and fixed number of clusters, denoted by K. When K is unknown, however, using model-selection criteria to choose its optimal value might become computationally expensive, especially in DL as the training process would have to be repeated numerous times. In this work, we bridge this gap by introducing an effective deep-clustering method that does not require knowing the value of K as it infers it during the learning. Using a split/merge framework, a dynamic architecture that adapts to the changing K, and a novel loss, our proposed method outperforms existing nonparametric methods (both classical and deep ones). While the very few existing deep nonparametric methods lack scalability, we demonstrate ours by being the first to report the performance of such a method on ImageNet. We also demonstrate the importance of inferring K by showing how methods that fix it deteriorate in performance when their assumed K value gets further from the ground-truth one, especially on imbalanced datasets. Our code is available at https://github.com/BGU-CS-VIL/DeepDPM.

本文介绍了一种有效的深度聚类方法，该方法使用了分裂/合并框架、动态体系结构自适应于不断变化的聚簇数量K，并且不需要预先指定K值。论文证明了这种无需预先指定簇数的非参数方法在ImageNet等数据集上，超越了现有的基于深度学习和传统的非参数聚类方法，并展示了在数据集不平衡时，预先指定K值的方法的性能下降。

DeepDPM:未知聚类数的深度聚类