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deeplearning.ai Deep Neural Networks Deep L-layer Neural network

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Page 1: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

deeplearning.ai

Deep NeuralNetworks

Deep L-layerNeural network

Page 2: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

AndrewNg

What is a deep neural network?

logistic regression

1 hidden layer

2 hidden layers

5 hidden layers

Page 3: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

AndrewNg

Deep neural network notation

Page 4: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

deeplearning.ai

Deep NeuralNetworks

Forward Propagationin a Deep Network

Page 5: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

AndrewNg

Forward propagation in a deep network

Page 6: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

deeplearning.ai

Getting your matrixdimensions right

Deep Neural Networks

Page 7: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

Andrew Ng

Parameters !["] and "["]

$%&!&"

Page 8: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

Andrew Ng

Vectorized implementation

!"#!#"

Page 9: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

deeplearning.ai

Whydeeprepresentations?

DeepNeuralNetworks

Page 10: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

AndrewNg

Intuition about deep representation

!"

Page 11: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

AndrewNg

Circuit theory and deep learningInformally: There are functions you can compute with a “small” L-layer deep neural network that shallower networks require exponentially more hidden units to compute.

Page 12: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

deeplearning.ai

Building blocks ofdeep neural networks

Deep NeuralNetworks

Page 13: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

AndrewNg

Forward and backward functions

Page 14: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

AndrewNg

Forward and backward functions

Page 15: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code
Page 16: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code
Page 17: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code
Page 18: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

deeplearning.ai

Parameters vsHyperparameters

Deep Neural Networks

Page 19: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

Andrew Ng

What are hyperparameters?Parameters: ! " , % " ,! & , % & ,! ' , % ' …

Page 20: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

Andrew Ng

Applied deep learning is a very empirical process

cost !

# of iterations

Idea

Experiment Code

Page 21: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

deeplearning.ai

What does thishave to do with

the brain?

Deep Neural Networks

Page 22: r g.ai ork - Deep Learning · Andrew Ng Applied deep learning is a very empirical process cost ! # of iterations Idea Experiment Code

Andrew Ng

Forward and backward propagation!["] = #["]$ + &["]'["] = ( " (! " )![$] = #[$]'["] + &[$]'[$] = ( $ (! $ )

'[%] = ( % ! % = +,

-![%] = '[%] − +-#[%] = 1

0-! % ' % &

-&[%] = 1012. sum(d! % , 9:;< = 1, =>>2-;0< = ?@A>)

-![%'"] = -# % &-! % (( % (! %'" )

-#["] = 10-! " ' " &

-&["] = 1012. sum(d! " , 9:;< = 1, =>>2-;0< = ?@A>)

-!["] = -# % &-! $ (( " (! " )