Abstract
Natural-gradient methods enable fast and simple algorithms for variational
inference, but due to computational difficulties, their use is mostly limited
to minimal exponential-family (EF) approximations. In this paper, we
extend their application to estimate structured approximations such as
mixtures of EF distributions. Such approximations can fit complex, multimodal
posterior distributions and are generally more accurate than unimodal EF
approximations. By using a minimal conditional-EF representation of such
approximations, we derive simple natural-gradient updates. Our empirical
results demonstrate a faster convergence of our natural-gradient method
compared to black-box gradient-based methods. Our work expands the scope of
natural gradients for Bayesian inference and makes them more widely applicable
than before.
Users
Please
log in to take part in the discussion (add own reviews or comments).