Flexible and efficient implementations of Bayesian independent component analysis

In this paper we present an empirical Bayes method for flexible and efficient Independent Component Analysis (ICA). The method is flexible with respect to choice of source prior, dimensionality and positivity of the mixing matrix, and structure of the noise covariance matrix. The efficiency is ensured using parameter optimizers which are more advanced than the expectation maximization (EM) algorithm, but still easy to implement. These optimizers are the overrelaxed adaptive EM algorithm and the easy gradient recipe. The required expectations over the source posterior are estimated with accurate mean field methods: variational and the expectation consistent framework. We demonstrate the usefulness of the approach with the publicly available Matlab toolbox icaMF.