Mark who I met in machine learning study meetup had recommended me to study a research paper about discrete variational autoencoder. I have read today. As so does variational inference, it includes many mathematical equations, but what the author wants to tell was very straightforward. Two previous posts, Variational Method, Independent Component Analysis, are relevant to the following discussion. Autoencoder To understand the paper, above all, we need to know what the autoencoder is and what variational autoencoder is.