1. INTRODUCTION
Domain adaptation aims to alleviate the need for labelled examples in a given target domain using knowledge transferred from a related source domain, such as across image data of different camera types [1]. Domain adaptation (DA) is a very well studied topic with numerous competing methods [1]. Clustering-based DA approaches group unlabelled target domain data examples that are likely to belong to the same class. One area of DA where clustering methods are particularly useful is that of heterogeneous domain adaptation—where the target domain contains novel classes compared to the source domain. For DA problems of this type, clustering-based DA methods [2], [3] provide one of the only solutions.