dataHacker.rs
Introduction to
Neural Networks
dataHacker.rs
NN Intro
 Logistic Regression
 Forward Propagation
 Cost Function
 Backward Propagation
 Neural Network
 Brain Analogy
 Logistic Regression Implementation
dataHacker.rs
Logistic Regression
 Supervised learning algorithm
 Binary classification problem
 Labels: 0 or 1
 Example: cat picture
dataHacker.rs
Logistic Regression
Linear function
 Parameters: w, b
Sigmoid Activation function
 Range 0-1
“weights”
“bias vector”
“input data”
“output”
dataHacker.rs
Simple Neuron
Logistic regression
 One neuron – two functions
 1 -Linear function
 2 - Activation function
dataHacker.rs
Computation Graph
Forward propagation & Backward propagation
 Cost Function
 Measures how well our
algorithm is working
dataHacker.rs
Key components
Three key components to train Neural Networks
 1. Score function (Linear+Activation)
 2. Loss Function
 3. Optimization
dataHacker.rs
Forward propagation
“input data”
“weight”
“bias” Linear function Activation function Loss function
Logistic Regression
dataHacker.rs
Cost Function
How our algorithm
works?
Visualizing the cost
function
dataHacker.rs
Backward propagation
 Optimization
 Gradient descent
 Learning rate
What is the correct value
of parameters?
dataHacker.rs
Backward propagation
 Gradient of L with respect to parameters
 Calculate derivatives
 Local gradient X Upstream gradient
dataHacker.rs
Neural Network
Input layer
Hidden layers
Output layer
dataHacker.rs
Neural Network
Logistic Regression
Neural Network with 5
hidden layers
“shallow”
“shallow” “shallow”
“deep”
Neural Network with single
hidden layer
Neural Network with 2
hidden layers
dataHacker.rs
Brain Analogy
dataHacker.rs
Logistic Regression
Implementation
dataHacker.rs
Logistic Regression
Implementation
dataHacker.rs
Logistic Regression
Implementation
dataHacker.rs
Logistic Regression
Implementation
dataHacker.rs
Logistic Regression
Implementation
dataHacker.rs
Logistic Regression
Implementation
dataHacker.rs
Logistic Regression
Implementation
dataHacker.rs
Logistic Regression
Implementation
dataHacker.rs
Logistic Regression
Implementation
dataHacker.rs
Logistic Regression
Implementation
dataHacker.rs
Logistic Regression
Implementation

Introduction to Neural Networks with Python