model that are used for training with maximum likelihood so the key insight of generative Ebersole networks is to use supervised learning to estimate a ratio that we need to be able to do unsupervised learning there are also a variety of other papers by Shakir Muhammad and his collaborators and Sebastian knows and his collaborators that talk a lot about the different divergences that you can learn with these kinds of techniques and how this estimation procedure compares to other techniques have also been developed in the statistical estimation