Modelling Group-Switching in Cluster Analysis via Compositional Mixture Components
摘要
A non-Markovian framework for detecting and modelling observations that change groups across variables is introduced. This framework takes advantage of the concept of missing data, allowing straightforward implementation using the expectation-maximization algorithm for Gaussian mixture models. Importantly, the components used to model group-switching behaviour require only one additional free parameter to be estimated: making it a feasible approach for detecting and modelling rare group-switching events. We motivate the concepts underlying the techniques through simple examples, provide details for the model-fitting algorithms, and discuss results on real data.