Tutorial: Variational Inference and Expectation Maximization Graphical models are easily cosntructed to describe structure of virtually any problem. However, inference in most models is intractable. In this lecture, various approximate techniques that speed up inference are presented and compared on a single graphical model. Also, algorithms such as Bayesian inference, EM, Variational inference, Belief propagation, and Gibbs sampling are derived starting from a single energy function.