Multistream Regression with Asynchronous Concept Drift Detection

A recently introduced problem setting, referred as multistream, involves two independent non-stationary data generating processes. One of them is called source stream, which generates continuous data instances with true output. And the other one called target stream, which generates data instances lacking of true output. Due to the nature of data streams, scholars have addressed prediction problems under scenarios such as covariate shift or concept drift in past studies by discussing one assumption while keeping others consistent. For example, it is assumed that the data distributions of training and testing data are similar, and true output values of the stream instances would be available soon. However, in practice these assumptions are not always valid. The multistream regression problem is to predict the output of target stream, using data instances and their true output from source stream. In this paper, we propose an approach of multistream regression by incorporating concept drift detection into covariate shift adaptation. Meanwhile, empirical evaluation on synthetic and real world datasets demonstrates the effectiveness of the proposed technique by competing with the state-of-the-art approaches. Experiment results indicate that our method significantly improved prediction performance compared to existing benchmark.