AI入门之——Andrew Ng “Machine Learning”课程学习笔记第五周

5、Neural Networks:Learning

5.1、Cost Function and Backpropagation

5_1

5.2、Backprogation algorithm

5_2

5.3、Gradient checking

5_3

Important:
Be sure to disable your gradient checking code before training your claaifier. otherwise code will be very slow.

5.4 Random initialization

initial each initialtheta to a random value in[-EPSILON,EPSILON]

5.5 Put it together

5_4

5_5