FLEXIBLE ONLINE MULTIVARIATE REGRESSION WITH VARIATIONAL BAYES AND THE MATRIX-VARIATE DIRICHLET PROCESS

Flexible density regression methods, in which the whole distribution of a response vector changes with the covariates, are very useful in some applications. A recently developed technique of this kind uses the matrix-variate Dirichlet process as a prior for a mixing distribution on a coefficient in a multivariate linear regression model. The method is attractive for the convenient way that it allows borrowing strength across different component regressions and for its computational simplicity and tractability. The purpose of the present article is to develop fast online variational Bayes approaches to fitting this model, and to investigate how they perform compared to MCMC and batch variational methods in a number of scenarios.