Semi-Supervised Clustering via Information-Theoretic Markov Chain Aggregation
This addresses clustering problems where limited labeled data is available, but it appears incremental as it extends an existing framework to incorporate constraints.
The paper tackles semi-supervised clustering by connecting it to constrained Markov aggregation, introducing Constrained Markov Clustering (CoMaC) as an extension of an information-theoretic framework, and shows it is competitive with state-of-the-art methods.
We connect the problem of semi-supervised clustering to constrained Markov aggregation, i.e., the task of partitioning the state space of a Markov chain. We achieve this connection by considering every data point in the dataset as an element of the Markov chain's state space, by defining the transition probabilities between states via similarities between corresponding data points, and by incorporating semi-supervision information as hard constraints in a Hartigan-style algorithm. The introduced Constrained Markov Clustering (CoMaC) is an extension of a recent information-theoretic framework for (unsupervised) Markov aggregation to the semi-supervised case. Instantiating CoMaC for certain parameter settings further generalizes two previous information-theoretic objectives for unsupervised clustering. Our results indicate that CoMaC is competitive with the state-of-the-art.