Lecture 1 Neutral Network

1. Learning is looking for a function

Three questions for Training procedure

Model Architecture

classification task binary Classification and Multi-class Classification, but some cases are not easy to be formulated as classification problems.

A single layer of Neutrons (Perceptron)

This bias term is an "always on" feature.

A single neuron can only handle binary classification.

Limitation of Perceptron

Neuron Network Model (Multi-layer Perceptron)

non-linear activation function is usually used in neural network.

What does the "Good" Function mean?

Loss Function design

Function = model parameters

Model Parameter Measurement

Optimization

How to find out the best function

Gradient Descent for Optimization

Stochastic gradient descent (SGD)

Mini-batch SGD

Mini-batch is more effective.

Practical tips

different initialization parameters, set them randomly

Tips for mini-batch training

shuffle training samples before every epoch

Possible solutions

more training samples

some tips:dropout, etc