Novel Class Discovery: A Dependency Approach

Abstract

Supervised and semi-supervised algorithms have been designed under a closed-world setting, with the assumption that unlabeled data consists of classes previously seen in labeled training data. However, real world is inherently open set where this assumption is often violated, and thus novel data may be encountered in test data. In this paper, we look at the problem where the model is required to discover novel classes never encountered in the labeled set. We propose a dependency measure based on Squared Mutual Information (SMI) where we simultaneously learn to classify and cluster the data. Our experiments show that our approach is able to achieve competitive performance on CIFAR and Imagenet datasets.