Deep Auto-encoder Symmetric is not necessary. Of course,the auto-encoder can be deep As close as possible W2 Initialize by RBM Code layer-by-layer Reference:Hinton,Geoffrey E.,and Ruslan R.Salakhutdinov."Reducing the dimensionality of data with neural networks."Science 313.5786(2006):504-507 Initialize by RBM layer-by-layer Reference: Hinton, Geoffrey E., and Ruslan R. Salakhutdinov. "Reducing the dimensionality of data with neural networks." Science 313.5786 (2006): 504-507 • Of course, the auto-encoder can be deep Deep Auto-encoder Input Layer Layer Layer bottle Output Layer Layer Layer Layer Layer … … Code As close as possible 𝑥 𝑥 ො 𝑊1 𝑊1 𝑇 𝑊2 𝑊2 𝑇 Symmetric is not necessary