1 本章简要记录

         “Deep learning methods are representation-learning methods with multiple levels of representation, obtained by composing simple but nonlinear modules that each transform the representation at one level (starting with the raw input) into a representation at a higher, slightly more abstract level. [. . . ] The key aspect of deep learning is that these layers are not designed by human engineers: they are learned from data using a general-purpose learning procedure” – Yann LeCun, Yoshua Bengio, and Geoffrey Hinton, Nature 2015. [9]         “Deep learning meth